Existing Annotations Review

GO Term	Evidence	Action	Reason
GO:0000272 polysaccharide catabolic process	IEA GO_REF:0000120	MARK AS OVER ANNOTATED	Summary: This annotation is misleading for CbpA. CbpA is a non-catalytic scaffoldin that organizes enzymes but does not itself catalyze polysaccharide catabolism. The cellulosome complex as a whole participates in this process, but attributing it to the scaffoldin alone misrepresents its role. Reason: CbpA is a structural/organizational protein, not a catalytic enzyme. While it enables polysaccharide catabolism by organizing enzymes, it does not directly participate in the catabolic reaction. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome
GO:0005576 extracellular region	IEA GO_REF:0000044	ACCEPT	Summary: This annotation is correct. CbpA contains an N-terminal signal peptide (residues 1-28) and is secreted to the extracellular space where it assembles into the cellulosome complex. It remains associated with the cell surface. Reason: UniProt clearly documents the signal peptide and states "Secreted. Note=Remains at the cell surface." The literature confirms CbpA functions extracellularly. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md CbpA contains a Sec-type signal peptide and is secreted, assembling into an extracellular cellulosome
GO:0005975 carbohydrate metabolic process	IEA GO_REF:0000002	MARK AS OVER ANNOTATED	Summary: This annotation is too general and misrepresents CbpA's role. CbpA does not metabolize carbohydrates; it organizes enzymes that do. This is an overly broad annotation derived from domain composition. Reason: CbpA is non-catalytic. It facilitates carbohydrate metabolism by organizing catalytic enzymes, but does not itself perform any metabolic reaction. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome
GO:0030245 cellulose catabolic process	IEA GO_REF:0000043	MARK AS OVER ANNOTATED	Summary: This annotation is misleading. CbpA itself does not catabolize cellulose. It organizes the cellulosome to facilitate cellulose catabolism by the assembled enzymes, but the scaffoldin has no catalytic activity. Reason: As a non-catalytic scaffoldin, CbpA enables but does not directly perform cellulose catabolism. The annotation should be on the catalytic enzymes, not the scaffoldin. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome
GO:0030246 carbohydrate binding	IEA GO_REF:0000002	ACCEPT	Summary: This annotation is correct. CbpA contains a CBM3 domain that binds carbohydrates, specifically crystalline cellulose. GO:0030248 (cellulose binding) would be more precise. Reason: The CBM3 domain mediates carbohydrate binding. This is a true positive but could be made more specific with GO:0030248. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md The CBM3 mediates binding of the assembled complex to crystalline cellulose
GO:0030248 cellulose binding	IEA GO_REF:0000002	ACCEPT	Summary: This annotation is correct and represents a core molecular function of CbpA. The CBM3 domain specifically binds crystalline cellulose, targeting the cellulosome to its substrate. Reason: Cellulose binding via CBM3 is a well-characterized function of CbpA, demonstrated experimentally. This is essential for targeting the cellulosome to substrate. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md The CBM3 mediates binding of the assembled complex to crystalline cellulose, increasing local enzyme concentration at the substrate
GO:0071555 cell wall organization	IEA GO_REF:0000043	REMOVE	Summary: This annotation is incorrect. CbpA is involved in degrading plant cell walls (as a target substrate), not in bacterial cell wall organization. The UniProt keyword mapping appears to have conflated cell wall degradation with cell wall organization. Reason: GO:0071555 refers to organization of the organism's own cell wall. CbpA is involved in degrading external plant cell wall material, which is a different process. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md CbpA ... creates a multienzyme complex that acts on plant cell wall polysaccharides
GO:0043263 cellulosome	TAS file:CLOCL/P38058/P38058-deep-research-falcon.md	NEW	Summary: CbpA is the primary structural component of the cellulosome. This cellular component annotation is essential for understanding CbpA's identity. Reason: CbpA IS the cellulosome scaffold. It is the primary scaffoldin that organizes the C. cellulovorans cellulosome complex. This annotation is critical. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome
GO:0044575 cellulosome assembly	TAS file:CLOCL/P38058/P38058-deep-research-falcon.md	NEW	Summary: CbpA's primary biological process is assembling the cellulosome by recruiting dockerin-bearing enzymes via its nine cohesin domains. Reason: CbpA assembles the cellulosome complex through cohesin-dockerin interactions. This is the primary biological process for this scaffoldin protein. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md It recruits dockerin-bearing enzymes (endoglucanases, exoglucanases, xylanases, etc.) via high-specificity cohesin–dockerin interactions
GO:1990308 type-I dockerin domain binding	TAS file:CLOCL/P38058/P38058-deep-research-falcon.md	NEW	Summary: CbpA contains nine type I cohesin domains that bind type I dockerins on cellulolytic enzymes. This is the primary molecular mechanism by which CbpA recruits enzymes. Reason: The cohesin-dockerin interaction is central to CbpA function. Nine cohesins provide the binding sites for dockerin-bearing enzymes. Supporting Evidence: file:CLOCL/P38058/P38058-deep-research-falcon.md nine cohesin repeats (type I cohesins) that recruit dockerin-bearing enzymatic subunits

Core Functions

CbpA binds crystalline cellulose via its CBM3 domain, targeting the cellulosome complex to its substrate for efficient degradation.

Molecular Function:

cellulose binding

Directly Involved In:

cellulosome assembly

Cellular Locations:

extracellular region

In Complex:

cellulosome

CbpA's nine type I cohesin domains bind type I dockerins on catalytic enzymes, recruiting them to the cellulosome complex and enabling its assembly.

Molecular Function:

type-I dockerin domain binding

Directly Involved In:

cellulosome assembly

Cellular Locations:

extracellular region

In Complex:

cellulosome

Supporting Evidence:

file:CLOCL/P38058/P38058-deep-research-falcon.md
nine cohesin repeats (type I cohesins) that recruit dockerin-bearing enzymatic subunits

References

GO_REF:0000002

Gene Ontology annotation through association of InterPro records with GO terms

GO_REF:0000043

Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping

GO_REF:0000044

Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping

GO_REF:0000120

Combined Automated Annotation using Multiple IEA Methods

file:CLOCL/P38058/P38058-deep-research-falcon.md

Deep research summary for P38058/cbpA

CbpA is non-catalytic scaffoldin with nine cohesin domains

"CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome"
CBM3 domain mediates cellulose binding

"The CBM3 mediates binding of the assembled complex to crystalline cellulose"
Cohesin domains recruit dockerin-bearing enzymes

"nine cohesin repeats (type I cohesins) that recruit dockerin-bearing enzymatic subunits"

Suggested Experiments

Experiment: Quantitative binding assays for each cohesin-dockerin pair to characterize specificity and affinity of CbpA cohesins.

Hypothesis: Different CbpA cohesins may have variable affinities for different dockerin-bearing enzymes, enabling preferential recruitment of certain enzymes.

Experiment: Structural characterization of CbpA cohesin domains by X-ray crystallography or cryo-EM to understand binding interfaces.

Hypothesis: Structural data would reveal molecular details of cohesin-dockerin recognition and explain observed binding specificities.

📚 Additional Documentation

Deep Research Falcon

(P38058-deep-research-falcon.md)

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gene_id: P38058
gene_symbol: cbpA
uniprot_accession: P38058
protein_description: 'RecName: Full=Cellulose-binding protein A; Flags: Precursor;'
gene_info: Name=cbpA;
organism_full: Clostridium cellulovorans.
protein_family: Not specified in UniProt
protein_domains: Carbo-bd_X2. (IPR005102); CBM2/CBM3_carb-bd_dom_sf. (IPR008965);
CBM3. (IPR001956); CBM3_sf. (IPR036966); Cohesin_dom. (IPR002102)
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Question

Gene Research for Functional Annotation

⚠️ CRITICAL: Gene/Protein Identification Context

BEFORE YOU BEGIN RESEARCH: You MUST verify you are researching the CORRECT gene/protein. Gene symbols can be ambiguous, especially for less well-characterized genes from non-model organisms.

Target Gene/Protein Identity (from UniProt):

UniProt Accession: P38058
Protein Description: RecName: Full=Cellulose-binding protein A; Flags: Precursor;
Gene Information: Name=cbpA;
Organism (full): Clostridium cellulovorans.
Protein Family: Not specified in UniProt
Key Domains: Carbo-bd_X2. (IPR005102); CBM2/CBM3_carb-bd_dom_sf. (IPR008965); CBM3. (IPR001956); CBM3_sf. (IPR036966); Cohesin_dom. (IPR002102)

MANDATORY VERIFICATION STEPS:

Check if the gene symbol "cbpA" matches the protein description above
Verify the organism is correct: Clostridium cellulovorans.
Check if protein family/domains align with what you find in literature
If you find literature for a DIFFERENT gene with the same or similar symbol, STOP

If Gene Symbol is Ambiguous or You Cannot Find Relevant Literature:

DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'cbpA' is ambiguous or literature is limited for this specific protein"
- Explain what you found (e.g., "Found extensive literature on a different gene with the same symbol in a different organism")
- Describe the protein based ONLY on the UniProt information provided above
- Suggest that the protein function can be inferred from domain/family information

Research Target:

Please provide a comprehensive research report on the gene cbpA (gene ID: P38058, UniProt: P38058) in CLOCL.

The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.

You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.

We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.

We are interested in where in or outside the cell the gene product carries out its function.

We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.

Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.

Output

Question: You are an expert researcher providing comprehensive, well-cited information.

Provide detailed information focusing on:
1. Key concepts and definitions with current understanding
2. Recent developments and latest research (prioritize 2023-2024 sources)
3. Current applications and real-world implementations
4. Expert opinions and analysis from authoritative sources
5. Relevant statistics and data from recent studies

Format as a comprehensive research report with proper citations. Include URLs and publication dates where available.
Always prioritize recent, authoritative sources and provide specific citations for all major claims.

Gene Research for Functional Annotation

⚠️ CRITICAL: Gene/Protein Identification Context

BEFORE YOU BEGIN RESEARCH: You MUST verify you are researching the CORRECT gene/protein. Gene symbols can be ambiguous, especially for less well-characterized genes from non-model organisms.

Target Gene/Protein Identity (from UniProt):

UniProt Accession: P38058
Protein Description: RecName: Full=Cellulose-binding protein A; Flags: Precursor;
Gene Information: Name=cbpA;
Organism (full): Clostridium cellulovorans.
Protein Family: Not specified in UniProt
Key Domains: Carbo-bd_X2. (IPR005102); CBM2/CBM3_carb-bd_dom_sf. (IPR008965); CBM3. (IPR001956); CBM3_sf. (IPR036966); Cohesin_dom. (IPR002102)

MANDATORY VERIFICATION STEPS:

Check if the gene symbol "cbpA" matches the protein description above
Verify the organism is correct: Clostridium cellulovorans.
Check if protein family/domains align with what you find in literature
If you find literature for a DIFFERENT gene with the same or similar symbol, STOP

If Gene Symbol is Ambiguous or You Cannot Find Relevant Literature:

DO NOT PROCEED WITH RESEARCH ON A DIFFERENT GENE. Instead:
- State clearly: "The gene symbol 'cbpA' is ambiguous or literature is limited for this specific protein"
- Explain what you found (e.g., "Found extensive literature on a different gene with the same symbol in a different organism")
- Describe the protein based ONLY on the UniProt information provided above
- Suggest that the protein function can be inferred from domain/family information

Research Target:

Please provide a comprehensive research report on the gene cbpA (gene ID: P38058, UniProt: P38058) in CLOCL.

The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.

You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.

We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.

We are interested in where in or outside the cell the gene product carries out its function.

We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.

Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.

Research report: cbpA (UniProt P38058) from Clostridium cellulovorans

Verification and identity
- Gene/protein: cbpA encodes the major cellulosomal scaffoldin Cellulose-binding protein A (CbpA), a large non-catalytic protein (~1,848 aa, historically observed as the P170 band) in the extracellular cellulosome of Clostridium cellulovorans (Gram-positive anaerobe). The original cloning/sequencing established an N-terminal signal peptide (~28 aa) and the overall length; subsequent biochemical work mapped multiple cohesin repeats and cellulose-binding capacity (sequence accession reported in 1992; UniProt maps this to P38058) (https://doi.org/10.1073/pnas.89.8.3483; Apr 1992) (shoseyov1992primarysequenceanalysis pages 1-2), (https://doi.org/10.1128/jb.183.18.5431-5435.2001; Sep 2001) (park2001cohesindockerininteractionsof pages 1-2), (https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w; Jan 2001) (doi2001theclostridiumcellulovorans pages 2-3).
- Ambiguity check: The cbpA symbol is used in other organisms for unrelated proteins; here, all cited work confirms C. cellulovorans scaffoldin CbpA (P38058) with CBM3 and cohesins in a cellulosome context. No switch to a different gene was made (shoseyov1992primarysequenceanalysis pages 1-2, park2001cohesindockerininteractionsof pages 1-2, doi2001theclostridiumcellulovorans pages 2-3).

Domain architecture and definitions
- Core modules: CbpA is a modular scaffoldin composed of an N-terminal Sec signal peptide; one cellulose-binding module of family 3 (CBM3) that binds crystalline cellulose; several hydrophilic X2 modules; and nine cohesin repeats (type I cohesins) that recruit dockerin-bearing enzymatic subunits (https://doi.org/10.1002/biot.202100064; Jun 2021) (tarraran2021cell‐surfacebindingdomains pages 1-2), (https://doi.org/10.1128/jb.183.18.5431-5435.2001; Sep 2001) (park2001cohesindockerininteractionsof pages 1-2), (https://doi.org/10.1073/pnas.89.8.3483; Apr 1992) (shoseyov1992primarysequenceanalysis pages 1-2).
- CBM3 concept: CBM3 (notably CBM3a) presents an extended planar surface that engages multiple cellulose chains, favoring crystalline cellulose binding and substrate-targeting of the complex. Contemporary analysis of CBMs 1/2/3 emphasizes their binding surface chemistry and utility in functionalizing cellulose materials (https://doi.org/10.1186/s40643-024-00790-4; Jul 2024) (li2024harnessingcellulosebindingprotein pages 1-3, li2024harnessingcellulosebindingprotein pages 3-5).
- X2 modules: X2 are small (~100 aa), hydrophilic non-catalytic modules common in mesophilic clostridial scaffoldins. Proposed roles include stabilizing adjacent domains and modulating interactions; X2 are not canonical carbohydrate-binding modules and often do not bind cellulose directly (summary of the C. cellulovorans/CipC literature and cross-species findings) (https://doi.org/10.3389/fmicb.2025.1638551; Sep 2025) (lindic2025structuralandfunctional pages 4-5, lindic2025structuralandfunctional pages 1-2).

Primary function and mechanism (current understanding)
- Scaffolding: CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome. It recruits dockerin-bearing enzymes (endoglucanases, exoglucanases, xylanases, etc.) via high-specificity cohesin–dockerin interactions to create a multienzyme complex that acts on plant cell wall polysaccharides (https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w; Jan 2001) (doi2001theclostridiumcellulovorans pages 2-3), (https://doi.org/10.1128/jb.183.18.5431-5435.2001; Sep 2001) (park2001cohesindockerininteractionsof pages 1-2).
- Substrate targeting: The CBM3 mediates binding of the assembled complex to crystalline cellulose, increasing local enzyme concentration at the substrate and promoting synergistic hydrolysis (https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w; Jan 2001) (doi2001theclostridiumcellulovorans pages 2-3), (https://doi.org/10.1186/s40643-024-00790-4; Jul 2024) (li2024harnessingcellulosebindingprotein pages 1-3, li2024harnessingcellulosebindingprotein pages 3-5).
- Cohesin set and specificities: Nine cohesins are present; different cohesin repeats exhibit different binding behaviors toward specific dockerin-bearing enzymes. For example, MalE-Coh6 bound EngE and ExgS in vitro, whereas MalE-Coh1 bound weakly; dockerin presence on enzymes such as EngB is required for binding to CbpA (https://doi.org/10.1128/jb.183.18.5431-5435.2001; Sep 2001) (park2001cohesindockerininteractionsof pages 1-2).

Cellular localization
- Secretory signal and extracellular location: CbpA contains a Sec-type signal peptide and is secreted, assembling into an extracellular cellulosome. The C. cellulovorans cellulosome is extracellular (~1×10^6 Da); anti-scaffoldin antibody blocks binding to cellulose and inhibits degradation, demonstrating extracellular substrate attachment function (https://doi.org/10.1073/pnas.89.8.3483; Apr 1992) (shoseyov1992primarysequenceanalysis pages 1-2), (https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w; Jan 2001) (doi2001theclostridiumcellulovorans pages 2-3).
- Cell surface association: C. cellulovorans can display its cellulosome on or near the cell surface, with attachment achieved via cell-surface modules in other scaffoldins or via noncovalent interactions; some clostridia assemble “free” (non-anchored) cellulosomes depending on scaffoldin composition (cross-species context) (2025 review) (santos2025unconventionalcohesindockerinbindingc pages 37-40, santos2025unconventionalcohesindockerinbindinga pages 37-40, santos2025unconventionalcohesindockerinbinding pages 37-40).

Interactions within the cellulosome
- Dockerin-bearing partners: Binding assays demonstrated CbpA cohesins interact with dockerins on several C. cellulovorans enzymes: EngE (endoglucanase), EngB (endoglucanase), ExgS (exoglucanase), among others; binding requires the dockerin module on the enzyme (https://doi.org/10.1128/jb.183.18.5431-5435.2001; Sep 2001) (park2001cohesindockerininteractionsof pages 1-2).
- Functional consequence: Antibody inhibition of the scaffoldin (P170/CbpA) blocked binding to cellulose and reduced crystalline cellulose hydrolysis, underscoring the essential scaffolding and substrate-attachment roles (https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w; Jan 2001) (doi2001theclostridiumcellulovorans pages 2-3).

Recent developments (emphasis 2023–2024)
- Genome-scale landscape of cellulosomes (2024): A comprehensive survey of 305,693 bacterial genomes identified 33 cellulosome-capable species and classified “simple” versus “complex” architectures. Clostridium-lineage microbes typically harbor simpler cellulosomes (fewer scaffoldin types) relative to Acetivibrio/Ruminococcus. The study underscores conserved cohesin–dockerin type specificity with known exceptions and the diversity of anchoring mechanisms, informing how C. cellulovorans CbpA fits among simple mesophilic clostridial systems (https://doi.org/10.3389/fmicb.2024.1473396; Oct 30, 2024) (minor2024agenomicanalysis pages 1-2).
- CBM3 structure–function in materials and catalysis (2024): A recent review details how CBM3’s planar binding surface engages three cellulose chains, and how CBM fusions or chemical coupling strategies are used to functionalize cellulose (immobilization, material strengthening, sensorization). These insights generalize to CbpA’s CBM3 in substrate targeting and serve as a platform for engineering (https://doi.org/10.1186/s40643-024-00790-4; Jul 2024) (li2024harnessingcellulosebindingprotein pages 1-3, li2024harnessingcellulosebindingprotein pages 3-5).
- X2 module status: Recent cross-species analyses argue X2 domains often stabilize adjacent domains rather than bind cellulose directly, refining older assumptions about X2 function in C. cellulovorans-like scaffoldins (summary) (https://doi.org/10.3389/fmicb.2025.1638551; Sep 2025) (lindic2025structuralandfunctional pages 4-5, lindic2025structuralandfunctional pages 1-2).

Current applications and implementations
- Synthetic scaffoldins and surface display using C. cellulovorans domains: A 2021 biotechnology study used domains from C. cellulovorans CbpA (CBM3 and X2) and EngE to build synthetic scaffoldins expressed and secreted by Lactococcus lactis. Only constructs bearing three EngE S-layer homology (SLH) modules bound the L. lactis surface, but the authors used CBM-based cellulose binding assays to track secretion/localization. This demonstrates practical reuse of C. cellulovorans CbpA-derived modules for designer cellulosomes and microbial surface display (https://doi.org/10.1002/biot.202100064; accepted May 19, 2021) (tarraran2021cell‐surfacebindingdomains pages 1-2).
- CBM-enabled cellulose functionalization (2024): CBM3 from cellulosomal scaffoldins is widely used to immobilize enzymes and add functions to cellulose; approaches include genetic fusion, noncovalent avidin/antibody adapters, and covalent “click” strategies. These platforms support biocatalysis, materials strengthening, and biomedical uses, highlighting the translational value of CbpA-like CBM3s (https://doi.org/10.1186/s40643-024-00790-4; Jul 2024) (li2024harnessingcellulosebindingprotein pages 1-3, li2024harnessingcellulosebindingprotein pages 3-5).

Expert assessment and quantitative/structural data
- Sequence and secretion: cbpA encodes ~1,848 aa with an N-terminal 28-aa signal peptide consistent with Sec-dependent secretion (PNAS 1992) (https://doi.org/10.1073/pnas.89.8.3483; Apr 1992) (shoseyov1992primarysequenceanalysis pages 1-2).
- Cohesin count and mapping: Nine cohesins with variable sequence identity (40–95% relative to a reference cohesin) were mapped; cohesins differ in binding to dockerin-bearing enzymes (J. Bacteriol. 2001) (https://doi.org/10.1128/jb.183.18.5431-5435.2001; Sep 2001) (park2001cohesindockerininteractionsof pages 1-2).
- Functional necessity in cellulose degradation: Antibody against the scaffoldin (P170) blocks cellulosome binding to cellulose and inhibits crystalline cellulose degradation (Chemical Record 2001) (https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w; Jan 2001) (doi2001theclostridiumcellulovorans pages 2-3).
- Cross-species cohesin–dockerin specificity (2024): Most cohesin–dockerin pairs maintain type-specific binding (Doc1↔Coh1, etc.) with noted exceptions; mesophilic Clostridium often classified as “simple” cellulosomes. This contextualizes C. cellulovorans CbpA’s nine cohesins as a relatively streamlined scaffoldin within the broader diversity (Frontiers in Microbiology 2024) (https://doi.org/10.3389/fmicb.2024.1473396; Oct 2024) (minor2024agenomicanalysis pages 1-2).

Key concepts and definitions (concise)
- Scaffoldin (CbpA): non-catalytic backbone that organizes cellulosomal enzymes via cohesin–dockerin binding, and targets cellulose through CBM3 (doi2001theclostridiumcellulovorans pages 2-3, park2001cohesindockerininteractionsof pages 1-2).
- CBM3: a carbohydrate-binding module with a planar binding face that binds crystalline cellulose; in scaffoldins, it concentrates enzyme activity on substrate (li2024harnessingcellulosebindingprotein pages 1-3, li2024harnessingcellulosebindingprotein pages 3-5).
- Cohesin–dockerin: species- and type-specific protein–protein interaction that assembles enzymes onto scaffoldins; C. cellulovorans CbpA harbors nine cohesins (park2001cohesindockerininteractionsof pages 1-2, minor2024agenomicanalysis pages 1-2).
- X2 module: small hydrophilic domain in clostridial scaffoldins; often stabilizing/structural rather than cellulose-binding per se (lindic2025structuralandfunctional pages 4-5, lindic2025structuralandfunctional pages 1-2).

Feature	Details	Evidence
Identity	Gene: cbpA; Protein: Cellulose-binding protein A (CbpA), ~1,848 aa; Organism: Clostridium cellulovorans; UniProt: P38058	Shoseyov et al. 1992 PNAS (sequence/size) https://doi.org/10.1073/pnas.89.8.3483 (shoseyov1992primarysequenceanalysis pages 1-2); Park et al. 2001 J Bacteriol (scaffoldin description) https://doi.org/10.1128/jb.183.18.5431-5435.2001 (park2001cohesindockerininteractionsof pages 1-2)
Domain architecture	N-terminal Sec signal peptide (~28 aa); one cellulose-binding module (CBM, family 3-like); multiple X2 (hydrophilic) modules; ~9 cohesin repeats (tandem Coh units); total large modular scaffoldin (~1.8 kb protein)	Tarraran et al. 2021 (CBM3/X2 used in synthetic scaffoldins) https://doi.org/10.1002/biot.202100064 (tarraran2021cell‐surfacebindingdomains pages 1-2); Park 2001 (nine cohesins mapped) (park2001cohesindockerininteractionsof pages 1-2); Shoseyov 1992 (signal peptide) (shoseyov1992primarysequenceanalysis pages 1-2)
Primary functions	Non-catalytic scaffoldin that: (1) anchors dockerin-bearing cellulolytic enzymes via cohesin–dockerin interactions; (2) binds crystalline cellulose via CBM to concentrate activity at substrate	Doi & Tamaru 2001 (functional role of P170 scaffoldin) https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w (doi2001theclostridiumcellulovorans pages 2-3); Park 2001 (cohesin–dockerin assembly) (park2001cohesindockerininteractionsof pages 1-2)
Localization	Secreted/extracellular; associates with the cell surface and/or forms extracellular (sometimes non-anchored) cellulosome complexes that attach to cellulose	Shoseyov 1992 (signal peptide & secretion) (shoseyov1992primarysequenceanalysis pages 1-2); Doi & Tamaru 2001 (extracellular P170, cell-surface attachment) (doi2001theclostridiumcellulovorans pages 2-3); Santos 2025 (notes free vs anchored scaffoldin architectures) (santos2025unconventionalcohesindockerinbindingc pages 37-40)
Key interactions	Dockerin-bearing enzymes shown to bind specific CbpA cohesins (examples: EngE, EngB, ExgS); individual cohesins show differential specificity/affinity (e.g., Coh6 binds EngE/ExgS; Coh1 showed weak binding in assays)	Park et al. 2001 binding assays (park2001cohesindockerininteractionsof pages 1-2)
Core evidence / practical uses	Primary sequence and secretion: Shoseyov et al. 1992 PNAS; cohesin mapping and enzyme-binding: Park et al. 2001 J Bacteriol; functional scaffoldin role: Doi & Tamaru 2001; CbpA-derived domains used for synthetic scaffoldins and surface display (engineering applications): Tarraran et al. 2021 Biotech J	(shoseyov1992primarysequenceanalysis pages 1-2, park2001cohesindockerininteractionsof pages 1-2, doi2001theclostridiumcellulovorans pages 2-3, tarraran2021cell‐surfacebindingdomains pages 1-2)

Table: Concise verification of Clostridium cellulovorans scaffoldin CbpA (UniProt P38058): identity, modular domain map, functions, localization, key enzyme interactions, and principal supporting sources for experimental evidence and engineering uses.

Limitations and open questions
- Direct 2023–2024 biochemical data on individual C. cellulovorans CbpA cohesin–dockerin affinities are limited; most quantitative mapping comes from earlier work. Recent advances largely derive from cross-species studies and CBM engineering literature (minor2024agenomicanalysis pages 1-2, li2024harnessingcellulosebindingprotein pages 1-3, li2024harnessingcellulosebindingprotein pages 3-5). Nevertheless, the core architecture and function of CbpA in C. cellulovorans are well established by primary sequence, secretion signals, cohesin mapping, and functional blocking experiments (shoseyov1992primarysequenceanalysis pages 1-2, park2001cohesindockerininteractionsof pages 1-2, doi2001theclostridiumcellulovorans pages 2-3).

References (with URLs and dates)
- Shoseyov O. et al. Primary sequence analysis of C. cellulovorans CbpA. PNAS. Apr 1992. https://doi.org/10.1073/pnas.89.8.3483 (shoseyov1992primarysequenceanalysis pages 1-2).
- Park J.-S. et al. Cohesin–dockerin interactions of C. cellulovorans cellulosomal subunits. J. Bacteriol. Sep 2001. https://doi.org/10.1128/jb.183.18.5431-5435.2001 (park2001cohesindockerininteractionsof pages 1-2).
- Doi R.H., Tamaru Y. The C. cellulovorans cellulosome. Chemical Record. Jan 2001. https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w (doi2001theclostridiumcellulovorans pages 2-3).
- Tarraran L. et al. Cell-surface binding domains from C. cellulovorans for surface display in L. lactis. Biotechnology Journal. Jun 2021. https://doi.org/10.1002/biot.202100064 (tarraran2021cell‐surfacebindingdomains pages 1-2).
- Li S., Liu G. Harnessing cellulose-binding protein domains for functionalized cellulose materials. Bioresources and Bioprocessing. Jul 2024. https://doi.org/10.1186/s40643-024-00790-4 (li2024harnessingcellulosebindingprotein pages 1-3, li2024harnessingcellulosebindingprotein pages 3-5).
- Minor C.M. et al. A genomic analysis reveals the diversity of cellulosome-displaying bacteria. Frontiers in Microbiology. Oct 30, 2024. https://doi.org/10.3389/fmicb.2024.1473396 (minor2024agenomicanalysis pages 1-2).
- Lindič N., Vodovnik M. Structural and functional insights into cellulosomes. Frontiers in Microbiology. Sep 2025. https://doi.org/10.3389/fmicb.2025.1638551 (for X2 module context across species) (lindic2025structuralandfunctional pages 4-5, lindic2025structuralandfunctional pages 1-2).

References

(shoseyov1992primarysequenceanalysis pages 1-2): O. Shoseyov, Masahiro Takagi, Marc A. Goldstein, and RoY H. Doit. Primary sequence analysis of clostridium cellulovorans cellulose binding protein a. Proceedings of the National Academy of Sciences of the United States of America, 89:3483-3487, Apr 1992. URL: https://doi.org/10.1073/pnas.89.8.3483, doi:10.1073/pnas.89.8.3483. This article has 224 citations and is from a highest quality peer-reviewed journal.
(park2001cohesindockerininteractionsof pages 1-2): Jae-Seon Park, Yutaka Matano, and Roy H. Doi. Cohesin-dockerin interactions of cellulosomal subunits of clostridium cellulovorans. Journal of Bacteriology, 183:5431-5435, Sep 2001. URL: https://doi.org/10.1128/jb.183.18.5431-5435.2001, doi:10.1128/jb.183.18.5431-5435.2001. This article has 33 citations and is from a peer-reviewed journal.
(doi2001theclostridiumcellulovorans pages 2-3): Roy H. Doi and Yutaka Tamaru. The clostridium cellulovorans cellulosome: an enzyme complex with plant cell wall degrading activity. Chemical record, 1 1:24-32, Jan 2001. URL: https://doi.org/10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w, doi:10.1002/1528-0691(2001)1:1<24::aid-tcr5>3.0.co;2-w. This article has 144 citations and is from a peer-reviewed journal.
(tarraran2021cell‐surfacebindingdomains pages 1-2): Loredana Tarraran, Chiara Gandini, Anna Luganini, and Roberto Mazzoli. Cell‐surface binding domains from clostridium cellulovorans can be used for surface display of cellulosomal scaffoldins in lactococcus lactis. Biotechnology Journal, Jun 2021. URL: https://doi.org/10.1002/biot.202100064, doi:10.1002/biot.202100064. This article has 13 citations and is from a peer-reviewed journal.
(li2024harnessingcellulosebindingprotein pages 1-3): Shaowei Li and Guodong Liu. Harnessing cellulose-binding protein domains for the development of functionalized cellulose materials. Bioresources and Bioprocessing, Jul 2024. URL: https://doi.org/10.1186/s40643-024-00790-4, doi:10.1186/s40643-024-00790-4. This article has 6 citations and is from a peer-reviewed journal.
(li2024harnessingcellulosebindingprotein pages 3-5): Shaowei Li and Guodong Liu. Harnessing cellulose-binding protein domains for the development of functionalized cellulose materials. Bioresources and Bioprocessing, Jul 2024. URL: https://doi.org/10.1186/s40643-024-00790-4, doi:10.1186/s40643-024-00790-4. This article has 6 citations and is from a peer-reviewed journal.
(lindic2025structuralandfunctional pages 4-5): Nataša Lindič and Maša Vodovnik. Structural and functional insights into cellulosomes: masters of plant cell wall degradation. Frontiers in Microbiology, Sep 2025. URL: https://doi.org/10.3389/fmicb.2025.1638551, doi:10.3389/fmicb.2025.1638551. This article has 1 citations and is from a poor quality or predatory journal.
(lindic2025structuralandfunctional pages 1-2): Nataša Lindič and Maša Vodovnik. Structural and functional insights into cellulosomes: masters of plant cell wall degradation. Frontiers in Microbiology, Sep 2025. URL: https://doi.org/10.3389/fmicb.2025.1638551, doi:10.3389/fmicb.2025.1638551. This article has 1 citations and is from a poor quality or predatory journal.
(santos2025unconventionalcohesindockerinbindingc pages 37-40): MRCD Santos. Unconventional cohesin-dockerin binding mechanisms reveal the complexity of cellulosome assembly. Unknown journal, 2025.
(santos2025unconventionalcohesindockerinbindinga pages 37-40): MRCD Santos. Unconventional cohesin-dockerin binding mechanisms reveal the complexity of cellulosome assembly. Unknown journal, 2025.
(santos2025unconventionalcohesindockerinbinding pages 37-40): MRCD Santos. Unconventional cohesin-dockerin binding mechanisms reveal the complexity of cellulosome assembly. Unknown journal, 2025.
(minor2024agenomicanalysis pages 1-2): Christine M. Minor, Allen Takayesu, Sung Min Ha, Lukasz Salwinski, Michael R. Sawaya, Matteo Pellegrini, and Robert T. Clubb. A genomic analysis reveals the diversity of cellulosome displaying bacteria. Frontiers in Microbiology, Oct 2024. URL: https://doi.org/10.3389/fmicb.2024.1473396, doi:10.3389/fmicb.2024.1473396. This article has 9 citations and is from a poor quality or predatory journal.

Citations

shoseyov1992primarysequenceanalysis pages 1-2
park2001cohesindockerininteractionsof pages 1-2
doi2001theclostridiumcellulovorans pages 2-3
minor2024agenomicanalysis pages 1-2
santos2025unconventionalcohesindockerinbindingc pages 37-40
li2024harnessingcellulosebindingprotein pages 1-3
li2024harnessingcellulosebindingprotein pages 3-5
lindic2025structuralandfunctional pages 4-5
lindic2025structuralandfunctional pages 1-2
santos2025unconventionalcohesindockerinbindinga pages 37-40
santos2025unconventionalcohesindockerinbinding pages 37-40
https://doi.org/10.1073/pnas.89.8.3483;
https://doi.org/10.1128/jb.183.18.5431-5435.2001;
https://doi.org/10.1002/1528-0691(2001
https://doi.org/10.1002/biot.202100064;
https://doi.org/10.1186/s40643-024-00790-4;
https://doi.org/10.3389/fmicb.2025.1638551;
https://doi.org/10.3389/fmicb.2024.1473396;
https://doi.org/10.1073/pnas.89.8.3483
https://doi.org/10.1128/jb.183.18.5431-5435.2001
https://doi.org/10.1002/biot.202100064
https://doi.org/10.1186/s40643-024-00790-4
https://doi.org/10.3389/fmicb.2024.1473396
https://doi.org/10.3389/fmicb.2025.1638551
https://doi.org/10.1073/pnas.89.8.3483,
https://doi.org/10.1128/jb.183.18.5431-5435.2001,
https://doi.org/10.1002/biot.202100064,
https://doi.org/10.1186/s40643-024-00790-4,
https://doi.org/10.3389/fmicb.2025.1638551,
https://doi.org/10.3389/fmicb.2024.1473396,

📄 View Raw YAML

id: P38058
gene_symbol: cbpA
product_type: PROTEIN
status: DRAFT
taxon:
  id: NCBITaxon:1493
  label: Clostridium cellulovorans
description: >-
  CbpA is the primary cellulosomal scaffoldin of Clostridium cellulovorans, a large
  non-catalytic protein (~1,848 aa) that serves as the organizational backbone for the
  cellulosome multi-enzyme complex. The protein contains an N-terminal signal peptide for
  secretion, one CBM3 (carbohydrate-binding module family 3) that binds crystalline cellulose,
  four X2 hydrophilic modules, and nine type I cohesin domains that recruit dockerin-bearing
  cellulolytic enzymes. CbpA targets the cellulosome to cellulose substrates and organizes
  multiple enzymes (endoglucanases, exoglucanases, xylanases) into a highly efficient
  degradative complex.
aliases:
  - P170
  - cellulose-binding protein A
  - scaffoldin
existing_annotations:
- term:
    id: GO:0000272
    label: polysaccharide catabolic process
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  review:
    summary: >-
      This annotation is misleading for CbpA. CbpA is a non-catalytic scaffoldin that
      organizes enzymes but does not itself catalyze polysaccharide catabolism. The
      cellulosome complex as a whole participates in this process, but attributing it
      to the scaffoldin alone misrepresents its role.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      CbpA is a structural/organizational protein, not a catalytic enzyme. While it
      enables polysaccharide catabolism by organizing enzymes, it does not directly
      participate in the catabolic reaction.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome"
- term:
    id: GO:0005576
    label: extracellular region
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  review:
    summary: >-
      This annotation is correct. CbpA contains an N-terminal signal peptide (residues 1-28)
      and is secreted to the extracellular space where it assembles into the cellulosome
      complex. It remains associated with the cell surface.
    action: ACCEPT
    reason: >-
      UniProt clearly documents the signal peptide and states "Secreted. Note=Remains at
      the cell surface." The literature confirms CbpA functions extracellularly.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "CbpA contains a Sec-type signal peptide and is secreted, assembling into an extracellular cellulosome"
- term:
    id: GO:0005975
    label: carbohydrate metabolic process
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  review:
    summary: >-
      This annotation is too general and misrepresents CbpA's role. CbpA does not
      metabolize carbohydrates; it organizes enzymes that do. This is an overly broad
      annotation derived from domain composition.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      CbpA is non-catalytic. It facilitates carbohydrate metabolism by organizing
      catalytic enzymes, but does not itself perform any metabolic reaction.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome"
- term:
    id: GO:0030245
    label: cellulose catabolic process
  evidence_type: IEA
  original_reference_id: GO_REF:0000043
  review:
    summary: >-
      This annotation is misleading. CbpA itself does not catabolize cellulose. It
      organizes the cellulosome to facilitate cellulose catabolism by the assembled
      enzymes, but the scaffoldin has no catalytic activity.
    action: MARK_AS_OVER_ANNOTATED
    reason: >-
      As a non-catalytic scaffoldin, CbpA enables but does not directly perform cellulose
      catabolism. The annotation should be on the catalytic enzymes, not the scaffoldin.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome"
- term:
    id: GO:0030246
    label: carbohydrate binding
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  review:
    summary: >-
      This annotation is correct. CbpA contains a CBM3 domain that binds carbohydrates,
      specifically crystalline cellulose. GO:0030248 (cellulose binding) would be more
      precise.
    action: ACCEPT
    reason: >-
      The CBM3 domain mediates carbohydrate binding. This is a true positive but could
      be made more specific with GO:0030248.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "The CBM3 mediates binding of the assembled complex to crystalline cellulose"
- term:
    id: GO:0030248
    label: cellulose binding
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  review:
    summary: >-
      This annotation is correct and represents a core molecular function of CbpA.
      The CBM3 domain specifically binds crystalline cellulose, targeting the cellulosome
      to its substrate.
    action: ACCEPT
    reason: >-
      Cellulose binding via CBM3 is a well-characterized function of CbpA, demonstrated
      experimentally. This is essential for targeting the cellulosome to substrate.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "The CBM3 mediates binding of the assembled complex to crystalline cellulose, increasing local enzyme concentration at the substrate"
- term:
    id: GO:0071555
    label: cell wall organization
  evidence_type: IEA
  original_reference_id: GO_REF:0000043
  review:
    summary: >-
      This annotation is incorrect. CbpA is involved in degrading plant cell walls
      (as a target substrate), not in bacterial cell wall organization. The UniProt
      keyword mapping appears to have conflated cell wall degradation with cell wall
      organization.
    action: REMOVE
    reason: >-
      GO:0071555 refers to organization of the organism's own cell wall. CbpA is involved
      in degrading external plant cell wall material, which is a different process.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "CbpA ... creates a multienzyme complex that acts on plant cell wall polysaccharides"
# NEW ANNOTATIONS
- term:
    id: GO:0043263
    label: cellulosome
  evidence_type: TAS
  original_reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
  review:
    summary: >-
      CbpA is the primary structural component of the cellulosome. This cellular
      component annotation is essential for understanding CbpA's identity.
    action: NEW
    reason: >-
      CbpA IS the cellulosome scaffold. It is the primary scaffoldin that organizes
      the C. cellulovorans cellulosome complex. This annotation is critical.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome"
- term:
    id: GO:0044575
    label: cellulosome assembly
  evidence_type: TAS
  original_reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
  review:
    summary: >-
      CbpA's primary biological process is assembling the cellulosome by recruiting
      dockerin-bearing enzymes via its nine cohesin domains.
    action: NEW
    reason: >-
      CbpA assembles the cellulosome complex through cohesin-dockerin interactions.
      This is the primary biological process for this scaffoldin protein.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "It recruits dockerin-bearing enzymes (endoglucanases, exoglucanases, xylanases, etc.) via high-specificity cohesin–dockerin interactions"
- term:
    id: GO:1990308
    label: type-I dockerin domain binding
  evidence_type: TAS
  original_reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
  review:
    summary: >-
      CbpA contains nine type I cohesin domains that bind type I dockerins on cellulolytic
      enzymes. This is the primary molecular mechanism by which CbpA recruits enzymes.
    action: NEW
    reason: >-
      The cohesin-dockerin interaction is central to CbpA function. Nine cohesins provide
      the binding sites for dockerin-bearing enzymes.
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "nine cohesin repeats (type I cohesins) that recruit dockerin-bearing enzymatic subunits"
references:
- id: GO_REF:0000002
  title: Gene Ontology annotation through association of InterPro records with GO terms
  findings: []
- id: GO_REF:0000043
  title: Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping
  findings: []
- id: GO_REF:0000044
  title: Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping
  findings: []
- id: GO_REF:0000120
  title: Combined Automated Annotation using Multiple IEA Methods
  findings: []
- id: file:CLOCL/P38058/P38058-deep-research-falcon.md
  title: Deep research summary for P38058/cbpA
  findings:
    - statement: CbpA is non-catalytic scaffoldin with nine cohesin domains
      supporting_text: "CbpA is the primary non-catalytic backbone of the C. cellulovorans cellulosome"
    - statement: CBM3 domain mediates cellulose binding
      supporting_text: "The CBM3 mediates binding of the assembled complex to crystalline cellulose"
    - statement: Cohesin domains recruit dockerin-bearing enzymes
      supporting_text: "nine cohesin repeats (type I cohesins) that recruit dockerin-bearing enzymatic subunits"
core_functions:
  - description: >-
      CbpA binds crystalline cellulose via its CBM3 domain, targeting the cellulosome
      complex to its substrate for efficient degradation.
    molecular_function:
      id: GO:0030248
      label: cellulose binding
    directly_involved_in:
      - id: GO:0044575
        label: cellulosome assembly
    locations:
      - id: GO:0005576
        label: extracellular region
    in_complex:
      id: GO:0043263
      label: cellulosome
  - description: >-
      CbpA's nine type I cohesin domains bind type I dockerins on catalytic enzymes,
      recruiting them to the cellulosome complex and enabling its assembly.
    molecular_function:
      id: GO:1990308
      label: type-I dockerin domain binding
    directly_involved_in:
      - id: GO:0044575
        label: cellulosome assembly
    locations:
      - id: GO:0005576
        label: extracellular region
    in_complex:
      id: GO:0043263
      label: cellulosome
    supported_by:
      - reference_id: file:CLOCL/P38058/P38058-deep-research-falcon.md
        supporting_text: "nine cohesin repeats (type I cohesins) that recruit dockerin-bearing enzymatic subunits"
proposed_new_terms: []
suggested_questions:
  - question: >-
      What is the binding affinity of each of the nine CbpA cohesin domains for different dockerins?
    experts: []
  - question: >-
      How does CbpA architecture compare to other clostridial scaffoldins?
    experts: []
suggested_experiments:
  - description: >-
      Quantitative binding assays for each cohesin-dockerin pair to characterize
      specificity and affinity of CbpA cohesins.
    hypothesis: >-
      Different CbpA cohesins may have variable affinities for different dockerin-bearing
      enzymes, enabling preferential recruitment of certain enzymes.
  - description: >-
      Structural characterization of CbpA cohesin domains by X-ray crystallography
      or cryo-EM to understand binding interfaces.
    hypothesis: >-
      Structural data would reveal molecular details of cohesin-dockerin recognition
      and explain observed binding specificities.

cbpA

Gene Description

Existing Annotations Review

Core Functions

CbpA binds crystalline cellulose via its CBM3 domain, targeting the cellulosome complex to its substrate for efficient degradation.

CbpA's nine type I cohesin domains bind type I dockerins on catalytic enzymes, recruiting them to the cellulosome complex and enabling its assembly.

References

Suggested Questions for Experts

Suggested Experiments

📚 Additional Documentation

Deep Research Falcon

Question

Gene Research for Functional Annotation

⚠️ CRITICAL: Gene/Protein Identification Context

Target Gene/Protein Identity (from UniProt):

MANDATORY VERIFICATION STEPS:

If Gene Symbol is Ambiguous or You Cannot Find Relevant Literature:

Research Target:

Output

Gene Research for Functional Annotation

⚠️ CRITICAL: Gene/Protein Identification Context

Target Gene/Protein Identity (from UniProt):

MANDATORY VERIFICATION STEPS:

If Gene Symbol is Ambiguous or You Cannot Find Relevant Literature:

Research Target:

Citations

📄 View Raw YAML