aroA (PP_1770) of Pseudomonas putida KT2440 is a 746-residue bifunctional cytoplasmic enzyme of aromatic amino acid biosynthesis. Its EPSP synthase module (3-phosphoshikimate 1-carboxyvinyltransferase, EC 2.5.1.19; 5-enolpyruvylshikimate-3-phosphate synthase) catalyzes the penultimate step of the shikimate pathway, transferring the enolpyruvyl moiety of phosphoenolpyruvate to the 5-hydroxyl of shikimate-3-phosphate to yield 5-enolpyruvylshikimate-3-phosphate (EPSP) plus inorganic phosphate; EPSP is then converted to chorismate, the branch-point precursor of phenylalanine, tyrosine, tryptophan, folate, ubiquinone, and other aromatic metabolites. In addition to the canonical EPSP synthase domain (Pfam EPSP_synthase; COG0128; TIGR01356 aroA), the protein carries an N-terminal prephenate/arogenate dehydrogenase (TyrA) module (Pfam PDH_N/PDH_C; COG0287) with a NAD(P)-binding Rossmann fold. UniProt annotates a second catalytic activity for this module, prephenate dehydrogenase (prephenate + NAD+ -> 4-hydroxyphenylpyruvate + CO2 + NADH, EC 1.3.1.12), placing it in the tyrosine-biosynthetic conversion of prephenate to 4-hydroxyphenylpyruvate. The protein is thus a fused EPSP-synthase / prephenate-dehydrogenase enzyme contributing to both chorismate formation and downstream L-tyrosine biosynthesis. The shikimate pathway is absent in animals, making EPSP synthase the molecular target of the herbicide glyphosate, a competitive inhibitor at the PEP site.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
|
GO:0003824
catalytic activity
|
IEA
GO_REF:0000002 |
MARK AS OVER ANNOTATED |
Summary: Root-level catalytic activity term; uninformative given the specific enzymatic activities annotated below.
Reason: GO:0003824 is the top-level molecular-function catalytic term and conveys no specific information. The protein has well-supported specific activities (EPSP synthase, EC 2.5.1.19; prephenate dehydrogenase, EC 1.3.1.12) that should be used instead.
|
|
GO:0003866
3-phosphoshikimate 1-carboxyvinyltransferase activity
|
IEA
GO_REF:0000120 |
ACCEPT |
Summary: EPSP synthase activity (EC 2.5.1.19); the canonical, core molecular function of aroA.
Reason: Directly supported by sequence/domain evidence: the EPSP synthase Pfam domain (PF00275), HAMAP rule MF_00210, COG0128, NCBIfam TIGR01356 (aroA), conserved PEP and shikimate-3-phosphate binding residues, and mapping to Rhea:21256 / EC 2.5.1.19. This is the defining function of aroA.
|
|
GO:0004665
prephenate dehydrogenase (NADP+) activity
|
IEA
GO_REF:0000002 |
KEEP AS NON CORE |
Summary: NADP+-dependent prephenate dehydrogenase activity inferred from the fused TyrA domain. The cofactor specificity (NADP+ vs NAD+) is not experimentally established for this protein.
Reason: The protein carries a genuine N-terminal prephenate/arogenate dehydrogenase (TyrA) module (Pfam PDH_N/PDH_C; COG0287), so prephenate dehydrogenase activity is a plausible second function. However, UniProt's curated CATALYTIC ACTIVITY block lists only the NAD+ route (EC 1.3.1.12), and the NADP+ specificity here is purely an InterPro electronic inference (IPR003099) with no cofactor evidence. Retain as a non-core, lower-confidence activity rather than a core function.
|
|
GO:0005737
cytoplasm
|
IEA
GO_REF:0000120 |
ACCEPT |
Summary: Cytoplasmic localization, consistent with a soluble shikimate-pathway metabolic enzyme.
Reason: EPSP synthase is a soluble cytosolic enzyme of central aromatic amino acid biosynthesis; cytoplasmic localization is supported by UniProt-SubCell (SL-0086) and HAMAP rule MF_00210, with no signal/transmembrane features.
|
|
GO:0006571
L-tyrosine biosynthetic process
|
IEA
GO_REF:0000120 |
KEEP AS NON CORE |
Summary: Tyrosine biosynthesis; supported via the fused prephenate dehydrogenase (TyrA) domain that converts prephenate to 4-hydroxyphenylpyruvate.
Reason: The TyrA (prephenate dehydrogenase) module places this protein in the tyrosine-specific branch (prephenate -> 4-hydroxyphenylpyruvate, UniPathway step 1/1 of the NAD+ route). This is a real but secondary process relative to the core EPSP synthase / chorismate-biosynthesis role, hence non-core.
|
|
GO:0008652
amino acid biosynthetic process
|
IEA
GO_REF:0000104 |
MARK AS OVER ANNOTATED |
Summary: General amino acid biosynthetic process; correct but non-specific given the more precise aromatic/chorismate terms.
Reason: True but high-level. The more specific processes (chorismate biosynthetic process, aromatic amino acid biosynthetic process, L-tyrosine biosynthetic process) capture the role precisely, making this generic parent redundant.
|
|
GO:0008977
prephenate dehydrogenase (NAD+) activity
|
IEA
GO_REF:0000120 |
KEEP AS NON CORE |
Summary: NAD+-dependent prephenate dehydrogenase activity from the fused TyrA domain; the second catalytic function of this bifunctional protein.
Reason: Supported by the prephenate/arogenate dehydrogenase domain (residues ~14-302; Pfam PDH_N/PDH_C; COG0287) and by UniProt's curated CATALYTIC ACTIVITY block citing the NAD+ reaction (Rhea:13869, EC 1.3.1.12) and the L-tyrosine biosynthesis (NAD+ route) pathway. This is the better-supported of the two prephenate dehydrogenase cofactor variants but remains the secondary (non-core) function relative to EPSP synthase.
|
|
GO:0009073
aromatic amino acid biosynthetic process
|
IEA
GO_REF:0000120 |
ACCEPT |
Summary: Aromatic amino acid biosynthesis; accurate at the family level for an EPSP-synthase / chorismate-pathway enzyme also feeding tyrosine biosynthesis.
Reason: Both functional modules act within aromatic amino acid biosynthesis: EPSP synthase produces the chorismate precursor common to Phe/Tyr/Trp, and the TyrA domain feeds the tyrosine branch. The term is appropriately specific.
|
|
GO:0009423
chorismate biosynthetic process
|
IEA
GO_REF:0000120 |
ACCEPT |
Summary: Chorismate biosynthesis; the core biological process of the EPSP synthase activity (penultimate shikimate-pathway step).
Reason: EPSP synthase catalyzes step 6/7 of chorismate biosynthesis from D-erythrose-4-phosphate and PEP (UniPathway UPA00053/UER00089). This is the most precise and well-supported biological-process term for the core function. Consistent with KT2440-specific metabolic-engineering evidence that tuning aroA expression contributes to flux through the shikimate pathway toward chorismate-derived products (see aroA-deep-research-falcon.md, citing PMID:41029715).
|
|
GO:0016491
oxidoreductase activity
|
IEA
GO_REF:0000104 |
MARK AS OVER ANNOTATED |
Summary: Generic oxidoreductase parent term covering the prephenate dehydrogenase activity.
Reason: Redundant high-level parent of the specific prephenate dehydrogenase activities (GO:0008977 / GO:0004665) already annotated. Provides no additional information beyond the specific terms.
|
|
GO:0016628
oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor
|
IEA
GO_REF:0000117 |
MARK AS OVER ANNOTATED |
Summary: Intermediate oxidoreductase-class parent term for the prephenate dehydrogenase activity.
Reason: A grouping parent of the specific prephenate dehydrogenase (NAD+/NADP+) activities. The leaf terms GO:0008977 / GO:0004665 are retained, so this mid-level class is redundant over-annotation.
|
|
GO:0016765
transferase activity, transferring alkyl or aryl (other than methyl) groups
|
IEA
GO_REF:0000002 |
MARK AS OVER ANNOTATED |
Summary: Generic enolpyruvyl/alkyl transferase parent term for the EPSP synthase activity.
Reason: High-level parent of the specific EPSP synthase activity (GO:0003866, enolpyruvyl transferase) which is retained. Redundant given the leaf term.
|
|
GO:0070403
NAD+ binding
|
IEA
GO_REF:0000002 |
KEEP AS NON CORE |
Summary: NAD+ cofactor binding by the Rossmann-fold prephenate dehydrogenase (TyrA) domain.
Reason: Consistent with the NAD(P)-binding Rossmann fold of the fused TyrA domain (InterPro IPR046826) and with the NAD+-dependent prephenate dehydrogenase activity. A supporting cofactor-binding term for the secondary activity, so non-core rather than a primary function.
|
Q: Is the prephenate dehydrogenase (TyrA) module of P. putida AroA catalytically active in vivo, and does it prefer NAD+ or NADP+ as cofactor?
Q: Does the AroA-TyrA domain fusion form a substrate channel or otherwise functionally couple chorismate biosynthesis with the tyrosine branch in P. putida?
Experiment: Heterologously express and purify Q88M05 and assay both EPSP synthase (S3P + PEP) and prephenate dehydrogenase (prephenate + NAD+/NADP+) activities to confirm bifunctionality and determine cofactor preference.
Experiment: Construct an aroA deletion/complementation in P. putida KT2440 and test for aromatic amino acid (and specifically tyrosine) auxotrophy to establish in vivo requirement of each catalytic module.
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.
The UniProt target Q88M05 is annotated as 3‑phosphoshikimate 1‑carboxyvinyltransferase (EC 2.5.1.19), also called 5‑enolpyruvylshikimate‑3‑phosphate synthase (EPSPS), classically encoded by aroA. EPSPS catalyzes the transfer of the enolpyruvyl group from phosphoenolpyruvate (PEP) to shikimate‑3‑phosphate (S3P) to form 5‑enolpyruvylshikimate‑3‑phosphate (EPSP) and inorganic phosphate, a penultimate step in the shikimate pathway leading to chorismate and aromatic amino acids. A key caveat for P. putida KT2440 is that historical pathway depictions contain an annotation inconsistency in which PP1770 is labeled as “TyrA” and simultaneously described with an EPSPS-like name; this should not be conflated with the well-established bacterial meaning of aroA = EPSPS. The most direct KT2440-specific functional evidence recovered here is pathway-engineering phenotypes: tuning aroA expression affected flux to the aromatic-derived product p‑aminobenzoic acid (pABA).
Verified target (user-supplied UniProt context): UniProt Q88M05, gene name aroA, ordered locus PP_1770, organism Pseudomonas putida KT2440.
Detected ambiguity in KT2440 literature: In a KT2440 aromatic-pathway analysis, PP1770 was presented in a pathway context as “PP1770 or TyrA” and described with dual functional labels including “prephenate dehydrogenase, putative/3‑phosphoshikimate 1‑carboxyvinyltransferase.” (molinahenares2009functionalanalysisof pages 2-4). This conflicts with the conventional assignment of tyrA to prephenate dehydrogenase and aroA to EPSPS, and it implies historical misannotation or figure-level conflation. Accordingly, this report treats Q88M05 as aroA/EPSPS (per UniProt target identity) and uses KT2440 papers only for statements they explicitly support.
| Category | Details | Quantitative data | Key sources (year; URL) | Notes |
|---|---|---|---|---|
| Verified target identity | UniProt Q88M05; gene aroA; ordered locus PP_1770; organism Pseudomonas putida KT2440 | — | Molina-Henares et al. 2009; https://doi.org/10.1111/j.1751-7915.2008.00062.x (molinahenares2009functionalanalysisof pages 2-4) | Literature for PP1770 in KT2440 exists, but direct biochemical characterization of Q88M05 in the retrieved sources is limited. |
| Core enzymatic function | 3-phosphoshikimate 1-carboxyvinyltransferase / 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19) catalyzes shikimate-3-phosphate (S3P) + phosphoenolpyruvate (PEP) → 5-enolpyruvylshikimate-3-phosphate (EPSP) + inorganic phosphate | Reaction stoichiometry shown; glyphosate can inhibit by occupying the PEP site | Shende et al. 2024; https://doi.org/10.1039/d3np00037k (shende2024theshikimatepathway pages 10-11, shende2024theshikimatepathway pages 50-64) | Current mechanistic understanding places EPSPS as an enolpyruvyl transferase acting through a tetrahedral intermediate; glyphosate is a competitive PEP-site inhibitor. |
| Pathway context | EPSPS performs the penultimate step of the shikimate pathway, leading to chorismate, the common precursor for phenylalanine, tyrosine, and tryptophan biosynthesis | — | Shende et al. 2024; https://doi.org/10.1039/d3np00037k (shende2024theshikimatepathway pages 10-11); Molina-Henares et al. 2009; https://doi.org/10.1111/j.1751-7915.2008.00062.x (molinahenares2009functionalanalysisof pages 2-4) | In bacteria this is a cytosolic metabolic enzyme in central aromatic amino-acid biosynthesis, inferred from pathway/structural context (shende2024theshikimatepathway pages 50-64). |
| Annotation inconsistency to flag | PP1770 was reported in one KT2440 pathway source as “PP1770 or TyrA” with dual/ambiguous labeling including “prephenate dehydrogenase, putative/3-phosphoshikimate 1-carboxyvinyltransferase” | — | Molina-Henares et al. 2009; https://doi.org/10.1111/j.1751-7915.2008.00062.x (molinahenares2009functionalanalysisof pages 2-4) | This is the main inconsistency that requires caution; the user-supplied UniProt entry specifically identifies Q88M05 as aroA/EPSPS, so literature must not be conflated with true tyrA/prephenate dehydrogenase studies. |
| P. putida KT2440 engineering relevance | In KT2440 pABA pathway optimization, aroA was included among shikimate-pathway genes tuned by combinatorial expression to improve production | Best strain produced 185.4 mg/L pABA; lowering aroA/aroK/aroQ/aroGD146N expression to native levels caused a 39.9% decrease in pABA in top strain S12 | Campos-Magaña et al. 2025; https://doi.org/10.1186/s13036-025-00553-5 (camposmagana2025combinatorialengineeringpinpoints pages 2-4, camposmagana2025combinatorialengineeringpinpoints pages 4-6, camposmagana2025combinatorialengineeringpinpoints pages 8-9) | Evidence supports aroA as a practical flux-control point in aromatic-pathway engineering in P. putida, although aroB was highlighted as the stronger bottleneck in that study. |
| Recent EPSPS developments (general) | Directed evolution platforms are being used to obtain EPSPS variants with both catalytic competence and glyphosate tolerance | One evolved EPSPS variant reached Ki ≈ 1 mM for glyphosate and ~2.5-fold improved enzymatic efficiency versus the starting enzyme | Reed et al. 2024; https://doi.org/10.1073/pnas.2317027121 (reed2024evolvingdualtraitepsp pages 1-2) | This is not P. putida-specific, but it is highly relevant to modern functional interpretation and real-world use of EPSPS enzymes. |
| Recent mechanistic expansion (general) | A 2024 study showed MurA can also catalyze S3P + PEP → EPSP + Pi in bryophytes, revealing an alternative route to EPSP formation | MurA activity was ~100-fold lower than EPSPS; MurA activity on S3P/PEP was ~8-fold higher than on its canonical substrate pair | Caygill et al. 2024; https://doi.org/10.1073/pnas.2412997121 (caygill2024muracatalyzedsynthesisof pages 1-2, caygill2024muracatalyzedsynthesisof pages 6-7) | Important for interpreting glyphosate tolerance biology broadly; not evidence that KT2440 uses MurA for this role. |
| Glyphosate resistance relevance | In bacteria, resistance can arise through target-site aroA mutations, EPSPS overproduction/gene amplification, transport/efflux changes, or glyphosate degradation/detoxification | Example selection range for Salmonella target-site mutants: 0.35–2 g/L glyphosate | Hertel et al. 2021; https://doi.org/10.1111/1462-2920.15534 (hertel2021molecularmechanismsunderlying pages 1-5, hertel2021molecularmechanismsunderlying pages 24-27, hertel2021molecularmechanismsunderlying pages 5-8, hertel2021molecularmechanismsunderlying pages 12-15) | These mechanisms frame how aroA function is exploited or bypassed under herbicide pressure. |
Table: This table summarizes the verified identity, biochemical function, pathway role, annotation caveats, and applied relevance of the target protein UniProt Q88M05 / aroA / PP_1770 from Pseudomonas putida KT2440. It also includes recent quantitative findings useful for interpreting EPSPS function and engineering significance.
EPSP synthase (EPSPS; EC 2.5.1.19) is an enolpyruvyl transferase in the shikimate pathway that catalyzes:
S3P + PEP → EPSP + Pi
This penultimate step installs a second PEP-derived unit onto the shikimate scaffold to form EPSP, which is then converted to chorismate in the final shikimate-pathway step (shende2024theshikimatepathway pages 10-11, shende2024theshikimatepathway pages 50-64).
A 2024 authoritative review describes EPSPS as an “alkyl transferase-type enzyme” operating through a tetrahedral intermediate, and emphasizes that EPSPS catalysis involves C–O bond cleavage of PEP (unusual among many PEP-utilizing enzymes, which often cleave P–O bonds) (shende2024theshikimatepathway pages 10-11).
EPSPS is also the canonical molecular target of glyphosate, which competitively occupies the PEP binding site, thereby preventing normal turnover and starving the cell of downstream aromatic amino acids (shende2024theshikimatepathway pages 10-11, hertel2021molecularmechanismsunderlying pages 1-5).
The same 2024 review summarizes three EPSPS “classes”: Class I (often glyphosate-sensitive; found in plants and some bacteria), Class II (microbial; variable sensitivity), and Class III (microbial; low identity to E. coli EPSPS) (shende2024theshikimatepathway pages 10-11). This classification is widely used to interpret glyphosate sensitivity and potential resistance routes.
EPSPS catalyzes the penultimate reaction of the shikimate pathway, which produces chorismate, the common precursor for phenylalanine, tyrosine, and tryptophan biosynthesis (shende2024theshikimatepathway pages 10-11, molinahenares2009functionalanalysisof pages 2-4). Because these amino acids are foundational building blocks and also feed numerous downstream aromatic metabolites, aroA/EPSPS is typically central to anabolic metabolism in bacteria.
The retrieved sources do not explicitly state subcellular localization for bacterial EPSPS. However, EPSPS is treated as a soluble metabolic enzyme in core carbon/anabolic metabolism, and bacterial structural context (e.g., E. coli EPSPS with S3P and glyphosate bound) supports the interpretation that it functions in the cytosol rather than in membranes or secretion pathways (shende2024theshikimatepathway pages 50-64).
A genome-wide mutant-library screen in KT2440 identified many conditionally essential genes for growth on glucose minimal medium and recovered multiple aromatic amino-acid auxotrophs, including mutants in tryptophan biosynthesis genes (trpA/D/C/E/G/F) and downstream aromatic genes such as pheA and tyrA (molina‐henares2010identificationofconditionally pages 2-3, molina‐henares2010identificationofconditionally pages 6-7). In the retrieved text segments, aroA/EPSPS itself is not explicitly reported as an identified conditionally essential locus (molina‐henares2010identificationofconditionally pages 2-3, molina‐henares2010identificationofconditionally pages 6-7). This absence could reflect library coverage, essentiality preventing recovery, annotation differences, or that aroA is discussed elsewhere (e.g., supplement) not retrieved here.
Separately, an aromatic biosynthesis functional study reports targeted phenotypes for pheA and tyrA in the PP1769–PP1770 region and documents aromatic amino-acid rescue patterns, but it likewise does not provide direct aroA/EPSPS phenotypes in the supplied pages (molinahenares2009functionalanalysisof pages 6-7).
A 2025 P. putida study optimizing production of the aromatic-derived compound p‑aminobenzoic acid (pABA) explicitly defines aroA as EPSPS (“3‑phosphoshikimate‑1‑carboxylvinyl transferase”) and places it in the shikimate pathway step converting S3P → EPSP (with PEP as donor) (camposmagana2025combinatorialengineeringpinpoints pages 2-4).
Using a Design-of-Experiments (Plackett–Burman) combinatorial expression approach across multiple shikimate-pathway genes, pABA titers ranged from ~2 mg/L to 186.2 mg/L in the initial screen (camposmagana2025combinatorialengineeringpinpoints pages 4-6). In their top strain (S12), pABA reached 185.40 mg/L, and reducing expression of aroA (together with aroK, aroQ, and aroGD146N) back to native levels caused a 39.9% decrease in pABA production (p = 0.001) (camposmagana2025combinatorialengineeringpinpoints pages 8-9). This provides KT2440-specific functional evidence that aroA expression level contributes measurably to aromatic-pathway flux toward a chorismate-derived product under engineered conditions.
A 2024 PNAS study developed a synthetic yeast selection system that enables simultaneous selection for glyphosate tolerance and retained/improved catalytic efficiency of EPSPS variants (reed2024evolvingdualtraitepsp pages 1-2). The study reports recovery of a mutant enzyme with Ki near 1 mM for glyphosate and approximately 2.5-fold improved enzymatic efficiency relative to the starting enzyme (reed2024evolvingdualtraitepsp pages 1-2). This work illustrates a modern trend: treating EPSPS as an engineerable biocatalyst where the classic “resistance vs activity” tradeoff can be mitigated with selection design and structural interpretation (reed2024evolvingdualtraitepsp pages 1-2, reed2024evolvingdualtraitepsp pages 5-6).
A second 2024 PNAS study reports that MurA (canonically involved in peptidoglycan biosynthesis) can catalyze the same net reaction as EPSPS (S3P + PEP → EPSP + Pi) in the bryophyte Marchantia polymorpha (caygill2024muracatalyzedsynthesisof pages 1-2). Enzyme assays showed MurA activity on S3P/PEP was ~100-fold lower than EPSPS, but ~8-fold higher than MurA’s activity on its canonical UDP-GlcNAc/PEP substrate pair (caygill2024muracatalyzedsynthesisof pages 6-7). Genetic and heterologous-expression evidence linked this alternative activity to glyphosate tolerance (caygill2024muracatalyzedsynthesisof pages 1-2). Although this is not a KT2440 result, it expands the conceptual landscape for “EPSP-forming enzymes,” which is relevant when interpreting resistance and evolutionary possibilities.
A 2024 Natural Product Reports review synthesizes EPSPS mechanism, inhibitor binding, structural information (including E. coli EPSPS complex with glyphosate; PDB 1G6S), and classification of enzyme classes relevant to predicting glyphosate sensitivity in different organisms (shende2024theshikimatepathway pages 10-11, shende2024theshikimatepathway pages 50-64). This is a high-authority source for current definitions and mechanistic consensus.
A domain-leading 2021 Environmental Microbiology review frames bacterial glyphosate resistance as arising via four broad mechanisms: (i) reduced EPSPS sensitivity or increased EPSPS production, (ii) degradation of glyphosate, (iii) detoxification/modification, and (iv) altered transport (reduced uptake/increased export) (hertel2021molecularmechanismsunderlying pages 1-5). This review provides concrete examples of aroA/EPSPS-associated target-site resistance (e.g., Pro101Ser; Gly96Ala) and emphasizes that overproduction (including amplification or promoter-up changes) can effectively titrate glyphosate (hertel2021molecularmechanismsunderlying pages 5-8). It also highlights non-target routes including transport and enzymatic modification (e.g., N-acetylation) that prevent EPSPS inhibition (hertel2021molecularmechanismsunderlying pages 12-15).
Quantitatively, the review reports laboratory selection of Salmonella aroA mutants under 0.35–2 g/L glyphosate, illustrating the selection pressures under which target-site changes can arise (hertel2021molecularmechanismsunderlying pages 5-8).
Industrial/biotech strain engineering of aromatic products: In P. putida KT2440, adjusting expression of shikimate-pathway genes including aroA is used to improve yields of chorismate-derived products such as pABA (camposmagana2025combinatorialengineeringpinpoints pages 2-4, camposmagana2025combinatorialengineeringpinpoints pages 8-9). This exemplifies aroA’s practical role as a flux-controlling node in aromatic anabolic pathways.
Glyphosate tolerance engineering: EPSPS variants (often bacterial-derived such as Agrobacterium CP4 EPSPS) are historically foundational for glyphosate-tolerant crops; modern 2024 work continues to refine EPSPS variants to improve both resistance and activity using high-throughput selection and structural analysis (hertel2021molecularmechanismsunderlying pages 5-8, reed2024evolvingdualtraitepsp pages 1-2).
Environmental/clinical microbiology implications: Because glyphosate targets EPSPS, environmental exposures can select for bacterial resistance via multiple mechanisms (target-site, transport, detoxification), potentially intersecting with broader stress-adaptation and resistance landscapes (hertel2021molecularmechanismsunderlying pages 1-5).
Despite extensive general knowledge on aroA/EPSPS, direct experimental characterization of UniProt Q88M05 in P. putida KT2440 (purified enzyme kinetics, substrate specificity beyond the canonical S3P/PEP reaction, structure, or explicit knockout essentiality) was not found in the retrieved KT2440 primary literature segments. The report therefore relies on: (i) authoritative EPSPS mechanism reviews (shende2024theshikimatepathway pages 10-11, shende2024theshikimatepathway pages 50-64), and (ii) KT2440-specific engineering phenotypes involving aroA expression (camposmagana2025combinatorialengineeringpinpoints pages 8-9), while explicitly flagging KT2440 annotation inconsistencies (molinahenares2009functionalanalysisof pages 2-4).
References
(molinahenares2009functionalanalysisof pages 2-4): M. A. Molina-Henares, Adela García‐Salamanca, A. Molina-Henares, J. de la Torre, M. C. Herrera, J. Ramos, and E. Duque. Functional analysis of aromatic biosynthetic pathways in pseudomonas putida kt2440. Microbial biotechnology, 2:91-100, Dec 2009. URL: https://doi.org/10.1111/j.1751-7915.2008.00062.x, doi:10.1111/j.1751-7915.2008.00062.x. This article has 32 citations and is from a peer-reviewed journal.
(shende2024theshikimatepathway pages 10-11): Vikram V. Shende, Katherine D. Bauman, and Bradley S. Moore. The shikimate pathway: gateway to metabolic diversity. Natural product reports, 41:604-648, Jan 2024. URL: https://doi.org/10.1039/d3np00037k, doi:10.1039/d3np00037k. This article has 173 citations and is from a peer-reviewed journal.
(shende2024theshikimatepathway pages 50-64): Vikram V. Shende, Katherine D. Bauman, and Bradley S. Moore. The shikimate pathway: gateway to metabolic diversity. Natural product reports, 41:604-648, Jan 2024. URL: https://doi.org/10.1039/d3np00037k, doi:10.1039/d3np00037k. This article has 173 citations and is from a peer-reviewed journal.
(camposmagana2025combinatorialengineeringpinpoints pages 2-4): Marco A Campos-Magaña, Sara Moreno-Paz, Maria Martin-Pascual, Vitor AP Martins dos Santos, Luis Garcia-Morales, and Maria Suarez-Diez. Combinatorial engineering pinpoints shikimate pathway bottlenecks in para-aminobenzoic acid production in pseudomonas putida. Journal of Biological Engineering, Sep 2025. URL: https://doi.org/10.1186/s13036-025-00553-5, doi:10.1186/s13036-025-00553-5. This article has 0 citations and is from a peer-reviewed journal.
(camposmagana2025combinatorialengineeringpinpoints pages 4-6): Marco A Campos-Magaña, Sara Moreno-Paz, Maria Martin-Pascual, Vitor AP Martins dos Santos, Luis Garcia-Morales, and Maria Suarez-Diez. Combinatorial engineering pinpoints shikimate pathway bottlenecks in para-aminobenzoic acid production in pseudomonas putida. Journal of Biological Engineering, Sep 2025. URL: https://doi.org/10.1186/s13036-025-00553-5, doi:10.1186/s13036-025-00553-5. This article has 0 citations and is from a peer-reviewed journal.
(camposmagana2025combinatorialengineeringpinpoints pages 8-9): Marco A Campos-Magaña, Sara Moreno-Paz, Maria Martin-Pascual, Vitor AP Martins dos Santos, Luis Garcia-Morales, and Maria Suarez-Diez. Combinatorial engineering pinpoints shikimate pathway bottlenecks in para-aminobenzoic acid production in pseudomonas putida. Journal of Biological Engineering, Sep 2025. URL: https://doi.org/10.1186/s13036-025-00553-5, doi:10.1186/s13036-025-00553-5. This article has 0 citations and is from a peer-reviewed journal.
(reed2024evolvingdualtraitepsp pages 1-2): Kevin B. Reed, Wantae Kim, Hongyuan Lu, Clayton T. Larue, Shirley Guo, Sierra M. Brooks, Michael R. Montez, James M. Wagner, Y. Jessie Zhang, and Hal S. Alper. Evolving dual-trait epsp synthase variants using a synthetic yeast selection system. Proceedings of the National Academy of Sciences of the United States of America, Aug 2024. URL: https://doi.org/10.1073/pnas.2317027121, doi:10.1073/pnas.2317027121. This article has 7 citations and is from a highest quality peer-reviewed journal.
(caygill2024muracatalyzedsynthesisof pages 1-2): Samuel Caygill, Thomas Köcher, and Liam Dolan. Mura-catalyzed synthesis of 5-enolpyruvylshikimate-3-phosphate confers glyphosate tolerance in bryophytes. Proceedings of the National Academy of Sciences of the United States of America, Nov 2024. URL: https://doi.org/10.1073/pnas.2412997121, doi:10.1073/pnas.2412997121. This article has 10 citations and is from a highest quality peer-reviewed journal.
(caygill2024muracatalyzedsynthesisof pages 6-7): Samuel Caygill, Thomas Köcher, and Liam Dolan. Mura-catalyzed synthesis of 5-enolpyruvylshikimate-3-phosphate confers glyphosate tolerance in bryophytes. Proceedings of the National Academy of Sciences of the United States of America, Nov 2024. URL: https://doi.org/10.1073/pnas.2412997121, doi:10.1073/pnas.2412997121. This article has 10 citations and is from a highest quality peer-reviewed journal.
(hertel2021molecularmechanismsunderlying pages 1-5): Robert Hertel, Johannes Gibhardt, Marion Martienssen, Ramona Kuhn, and Fabian M. Commichau. Molecular mechanisms underlying glyphosate resistance in bacteria. Jun 2021. URL: https://doi.org/10.1111/1462-2920.15534, doi:10.1111/1462-2920.15534. This article has 67 citations and is from a domain leading peer-reviewed journal.
(hertel2021molecularmechanismsunderlying pages 24-27): Robert Hertel, Johannes Gibhardt, Marion Martienssen, Ramona Kuhn, and Fabian M. Commichau. Molecular mechanisms underlying glyphosate resistance in bacteria. Jun 2021. URL: https://doi.org/10.1111/1462-2920.15534, doi:10.1111/1462-2920.15534. This article has 67 citations and is from a domain leading peer-reviewed journal.
(hertel2021molecularmechanismsunderlying pages 5-8): Robert Hertel, Johannes Gibhardt, Marion Martienssen, Ramona Kuhn, and Fabian M. Commichau. Molecular mechanisms underlying glyphosate resistance in bacteria. Jun 2021. URL: https://doi.org/10.1111/1462-2920.15534, doi:10.1111/1462-2920.15534. This article has 67 citations and is from a domain leading peer-reviewed journal.
(hertel2021molecularmechanismsunderlying pages 12-15): Robert Hertel, Johannes Gibhardt, Marion Martienssen, Ramona Kuhn, and Fabian M. Commichau. Molecular mechanisms underlying glyphosate resistance in bacteria. Jun 2021. URL: https://doi.org/10.1111/1462-2920.15534, doi:10.1111/1462-2920.15534. This article has 67 citations and is from a domain leading peer-reviewed journal.
(molina‐henares2010identificationofconditionally pages 2-3): M. Antonia Molina‐Henares, Jesús De La Torre, Adela García‐Salamanca, A. Jesús Molina‐Henares, M. Carmen Herrera, Juan L. Ramos, and Estrella Duque. Identification of conditionally essential genes for growth of pseudomonas putida kt2440 on minimal medium through the screening of a genome‐wide mutant library. Environmental Microbiology, 12:1468-1485, Jun 2010. URL: https://doi.org/10.1111/j.1462-2920.2010.02166.x, doi:10.1111/j.1462-2920.2010.02166.x. This article has 89 citations and is from a domain leading peer-reviewed journal.
(molina‐henares2010identificationofconditionally pages 6-7): M. Antonia Molina‐Henares, Jesús De La Torre, Adela García‐Salamanca, A. Jesús Molina‐Henares, M. Carmen Herrera, Juan L. Ramos, and Estrella Duque. Identification of conditionally essential genes for growth of pseudomonas putida kt2440 on minimal medium through the screening of a genome‐wide mutant library. Environmental Microbiology, 12:1468-1485, Jun 2010. URL: https://doi.org/10.1111/j.1462-2920.2010.02166.x, doi:10.1111/j.1462-2920.2010.02166.x. This article has 89 citations and is from a domain leading peer-reviewed journal.
(molinahenares2009functionalanalysisof pages 6-7): M. A. Molina-Henares, Adela García‐Salamanca, A. Molina-Henares, J. de la Torre, M. C. Herrera, J. Ramos, and E. Duque. Functional analysis of aromatic biosynthetic pathways in pseudomonas putida kt2440. Microbial biotechnology, 2:91-100, Dec 2009. URL: https://doi.org/10.1111/j.1751-7915.2008.00062.x, doi:10.1111/j.1751-7915.2008.00062.x. This article has 32 citations and is from a peer-reviewed journal.
(reed2024evolvingdualtraitepsp pages 5-6): Kevin B. Reed, Wantae Kim, Hongyuan Lu, Clayton T. Larue, Shirley Guo, Sierra M. Brooks, Michael R. Montez, James M. Wagner, Y. Jessie Zhang, and Hal S. Alper. Evolving dual-trait epsp synthase variants using a synthetic yeast selection system. Proceedings of the National Academy of Sciences of the United States of America, Aug 2024. URL: https://doi.org/10.1073/pnas.2317027121, doi:10.1073/pnas.2317027121. This article has 7 citations and is from a highest quality peer-reviewed journal.
id: Q88M05
gene_symbol: aroA
product_type: PROTEIN
status: COMPLETE
taxon:
id: NCBITaxon:160488
label: Pseudomonas putida (strain ATCC 47054 / DSM 6125 / CFBP 8728 / NCIMB 11950 / KT2440)
description: >-
aroA (PP_1770) of Pseudomonas putida KT2440 is a 746-residue bifunctional
cytoplasmic enzyme of aromatic amino acid biosynthesis. Its EPSP synthase
module (3-phosphoshikimate 1-carboxyvinyltransferase, EC 2.5.1.19;
5-enolpyruvylshikimate-3-phosphate synthase) catalyzes the penultimate step of
the shikimate pathway, transferring the enolpyruvyl moiety of
phosphoenolpyruvate to the 5-hydroxyl of shikimate-3-phosphate to yield
5-enolpyruvylshikimate-3-phosphate (EPSP) plus inorganic phosphate; EPSP is
then converted to chorismate, the branch-point precursor of phenylalanine,
tyrosine, tryptophan, folate, ubiquinone, and other aromatic metabolites. In
addition to the canonical EPSP synthase domain (Pfam EPSP_synthase; COG0128;
TIGR01356 aroA), the protein carries an N-terminal prephenate/arogenate
dehydrogenase (TyrA) module (Pfam PDH_N/PDH_C; COG0287) with a NAD(P)-binding
Rossmann fold. UniProt annotates a second catalytic activity for this module,
prephenate dehydrogenase (prephenate + NAD+ -> 4-hydroxyphenylpyruvate + CO2 +
NADH, EC 1.3.1.12), placing it in the tyrosine-biosynthetic conversion of
prephenate to 4-hydroxyphenylpyruvate. The protein is thus a fused
EPSP-synthase / prephenate-dehydrogenase enzyme contributing to both chorismate
formation and downstream L-tyrosine biosynthesis. The shikimate pathway is
absent in animals, making EPSP synthase the molecular target of the herbicide
glyphosate, a competitive inhibitor at the PEP site.
existing_annotations:
- term:
id: GO:0003824
label: catalytic activity
evidence_type: IEA
original_reference_id: GO_REF:0000002
qualifier: enables
review:
summary: Root-level catalytic activity term; uninformative given the specific enzymatic activities annotated below.
action: MARK_AS_OVER_ANNOTATED
reason: >-
GO:0003824 is the top-level molecular-function catalytic term and conveys
no specific information. The protein has well-supported specific activities
(EPSP synthase, EC 2.5.1.19; prephenate dehydrogenase, EC 1.3.1.12) that
should be used instead.
- term:
id: GO:0003866
label: 3-phosphoshikimate 1-carboxyvinyltransferase activity
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: enables
review:
summary: EPSP synthase activity (EC 2.5.1.19); the canonical, core molecular function of aroA.
action: ACCEPT
reason: >-
Directly supported by sequence/domain evidence: the EPSP synthase Pfam
domain (PF00275), HAMAP rule MF_00210, COG0128, NCBIfam TIGR01356 (aroA),
conserved PEP and shikimate-3-phosphate binding residues, and mapping to
Rhea:21256 / EC 2.5.1.19. This is the defining function of aroA.
- term:
id: GO:0004665
label: prephenate dehydrogenase (NADP+) activity
evidence_type: IEA
original_reference_id: GO_REF:0000002
qualifier: enables
review:
summary: NADP+-dependent prephenate dehydrogenase activity inferred from the fused TyrA domain. The cofactor specificity (NADP+ vs NAD+) is not experimentally established for this protein.
action: KEEP_AS_NON_CORE
reason: >-
The protein carries a genuine N-terminal prephenate/arogenate dehydrogenase
(TyrA) module (Pfam PDH_N/PDH_C; COG0287), so prephenate dehydrogenase
activity is a plausible second function. However, UniProt's curated
CATALYTIC ACTIVITY block lists only the NAD+ route (EC 1.3.1.12), and the
NADP+ specificity here is purely an InterPro electronic inference
(IPR003099) with no cofactor evidence. Retain as a non-core, lower-confidence
activity rather than a core function.
- term:
id: GO:0005737
label: cytoplasm
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: located_in
review:
summary: Cytoplasmic localization, consistent with a soluble shikimate-pathway metabolic enzyme.
action: ACCEPT
reason: >-
EPSP synthase is a soluble cytosolic enzyme of central aromatic amino acid
biosynthesis; cytoplasmic localization is supported by UniProt-SubCell
(SL-0086) and HAMAP rule MF_00210, with no signal/transmembrane features.
- term:
id: GO:0006571
label: L-tyrosine biosynthetic process
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: involved_in
review:
summary: Tyrosine biosynthesis; supported via the fused prephenate dehydrogenase (TyrA) domain that converts prephenate to 4-hydroxyphenylpyruvate.
action: KEEP_AS_NON_CORE
reason: >-
The TyrA (prephenate dehydrogenase) module places this protein in the
tyrosine-specific branch (prephenate -> 4-hydroxyphenylpyruvate, UniPathway
step 1/1 of the NAD+ route). This is a real but secondary process relative
to the core EPSP synthase / chorismate-biosynthesis role, hence non-core.
- term:
id: GO:0008652
label: amino acid biosynthetic process
evidence_type: IEA
original_reference_id: GO_REF:0000104
qualifier: involved_in
review:
summary: General amino acid biosynthetic process; correct but non-specific given the more precise aromatic/chorismate terms.
action: MARK_AS_OVER_ANNOTATED
reason: >-
True but high-level. The more specific processes (chorismate biosynthetic
process, aromatic amino acid biosynthetic process, L-tyrosine biosynthetic
process) capture the role precisely, making this generic parent redundant.
- term:
id: GO:0008977
label: prephenate dehydrogenase (NAD+) activity
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: enables
review:
summary: NAD+-dependent prephenate dehydrogenase activity from the fused TyrA domain; the second catalytic function of this bifunctional protein.
action: KEEP_AS_NON_CORE
reason: >-
Supported by the prephenate/arogenate dehydrogenase domain (residues
~14-302; Pfam PDH_N/PDH_C; COG0287) and by UniProt's curated CATALYTIC
ACTIVITY block citing the NAD+ reaction (Rhea:13869, EC 1.3.1.12) and the
L-tyrosine biosynthesis (NAD+ route) pathway. This is the better-supported
of the two prephenate dehydrogenase cofactor variants but remains the
secondary (non-core) function relative to EPSP synthase.
- term:
id: GO:0009073
label: aromatic amino acid biosynthetic process
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: involved_in
review:
summary: Aromatic amino acid biosynthesis; accurate at the family level for an EPSP-synthase / chorismate-pathway enzyme also feeding tyrosine biosynthesis.
action: ACCEPT
reason: >-
Both functional modules act within aromatic amino acid biosynthesis: EPSP
synthase produces the chorismate precursor common to Phe/Tyr/Trp, and the
TyrA domain feeds the tyrosine branch. The term is appropriately specific.
- term:
id: GO:0009423
label: chorismate biosynthetic process
evidence_type: IEA
original_reference_id: GO_REF:0000120
qualifier: involved_in
review:
summary: Chorismate biosynthesis; the core biological process of the EPSP synthase activity (penultimate shikimate-pathway step).
action: ACCEPT
reason: >-
EPSP synthase catalyzes step 6/7 of chorismate biosynthesis from
D-erythrose-4-phosphate and PEP (UniPathway UPA00053/UER00089). This is the
most precise and well-supported biological-process term for the core
function. Consistent with KT2440-specific metabolic-engineering evidence that
tuning aroA expression contributes to flux through the shikimate pathway
toward chorismate-derived products (see aroA-deep-research-falcon.md,
citing PMID:41029715).
- term:
id: GO:0016491
label: oxidoreductase activity
evidence_type: IEA
original_reference_id: GO_REF:0000104
qualifier: enables
review:
summary: Generic oxidoreductase parent term covering the prephenate dehydrogenase activity.
action: MARK_AS_OVER_ANNOTATED
reason: >-
Redundant high-level parent of the specific prephenate dehydrogenase
activities (GO:0008977 / GO:0004665) already annotated. Provides no
additional information beyond the specific terms.
- term:
id: GO:0016628
label: oxidoreductase activity, acting on the CH-CH group of donors, NAD or NADP as acceptor
evidence_type: IEA
original_reference_id: GO_REF:0000117
qualifier: enables
review:
summary: Intermediate oxidoreductase-class parent term for the prephenate dehydrogenase activity.
action: MARK_AS_OVER_ANNOTATED
reason: >-
A grouping parent of the specific prephenate dehydrogenase (NAD+/NADP+)
activities. The leaf terms GO:0008977 / GO:0004665 are retained, so this
mid-level class is redundant over-annotation.
- term:
id: GO:0016765
label: transferase activity, transferring alkyl or aryl (other than methyl) groups
evidence_type: IEA
original_reference_id: GO_REF:0000002
qualifier: enables
review:
summary: Generic enolpyruvyl/alkyl transferase parent term for the EPSP synthase activity.
action: MARK_AS_OVER_ANNOTATED
reason: >-
High-level parent of the specific EPSP synthase activity (GO:0003866,
enolpyruvyl transferase) which is retained. Redundant given the leaf term.
- term:
id: GO:0070403
label: NAD+ binding
evidence_type: IEA
original_reference_id: GO_REF:0000002
qualifier: enables
review:
summary: NAD+ cofactor binding by the Rossmann-fold prephenate dehydrogenase (TyrA) domain.
action: KEEP_AS_NON_CORE
reason: >-
Consistent with the NAD(P)-binding Rossmann fold of the fused TyrA domain
(InterPro IPR046826) and with the NAD+-dependent prephenate dehydrogenase
activity. A supporting cofactor-binding term for the secondary activity, so
non-core rather than a primary function.
core_functions:
- description: >-
EPSP synthase (3-phosphoshikimate 1-carboxyvinyltransferase) catalyzing the
penultimate step of the shikimate pathway, the chorismate-yielding branch of
aromatic amino acid biosynthesis.
molecular_function:
id: GO:0003866
label: 3-phosphoshikimate 1-carboxyvinyltransferase activity
supported_by:
- reference_id: file:PSEPK/aroA/aroA-uniprot.txt
supporting_text: >-
Catalyzes the transfer of the enolpyruvyl moiety of phosphoenolpyruvate
(PEP) to the 5-hydroxyl of shikimate-3-phosphate (S3P) to produce
enolpyruvyl shikimate-3-phosphate and inorganic phosphate; EC 2.5.1.19;
EPSP synthase family; chorismate biosynthesis step 6/7.
- reference_id: file:PSEPK/aroA/aroA-deep-research-falcon.md
supporting_text: >-
aroA is annotated as 3-phosphoshikimate 1-carboxyvinyltransferase / EPSP
synthase (EC 2.5.1.19) catalyzing S3P + PEP -> EPSP + Pi, the penultimate
step of the shikimate pathway leading to chorismate, the common precursor
for Phe/Tyr/Trp biosynthesis.
directly_involved_in:
- id: GO:0009423
label: chorismate biosynthetic process
# NOTE: The fused N-terminal prephenate/arogenate dehydrogenase (TyrA) module
# (prephenate dehydrogenase NAD+ activity, GO:0008977; L-tyrosine biosynthetic
# process, GO:0006571) is a genuine but secondary, non-core activity of this
# bifunctional protein and is reviewed as KEEP_AS_NON_CORE in existing_annotations
# rather than listed here as a core function.
references:
- id: GO_REF:0000002
title: Gene Ontology annotation through association of InterPro records with GO terms
findings: []
- id: GO_REF:0000104
title: Electronic Gene Ontology annotations created by transferring manual GO annotations between related proteins based on shared sequence features
findings: []
- id: GO_REF:0000117
title: Electronic Gene Ontology annotations created by ARBA machine learning models
findings: []
- id: GO_REF:0000120
title: Combined Automated Annotation using Multiple IEA Methods
findings: []
- id: file:PSEPK/aroA/aroA-deep-research-falcon.md
title: Deep research report (falcon) for aroA / EPSP synthase (Q88M05) in P. putida KT2440
findings:
- statement: Synthesizes EPSPS mechanism, shikimate-pathway/chorismate role, cytosolic localization inference, and KT2440-specific engineering evidence for aroA.
- id: PMID:12534463
title: Complete genome sequence and comparative analysis of the metabolically versatile Pseudomonas putida KT2440.
findings:
- statement: Genome sequence of P. putida KT2440 in which PP_1770 (aroA, Q88M05) is annotated, establishing the locus and organism context for this gene.
reference_section_type: RESULTS
reference_review:
relevance: MEDIUM
correctness: VERIFIED
review_notes: >-
PubMed-verified genome paper (Nelson et al., Environ Microbiol 2002) cited
in the UniProt entry as the source for the PP_1770 locus. Establishes
organism/locus, not direct enzymatic characterization.
- id: PMID:41029715
title: Combinatorial engineering pinpoints shikimate pathway bottlenecks in para-aminobenzoic acid production in Pseudomonas putida.
findings:
- statement: In P. putida KT2440 metabolic engineering for para-aminobenzoic acid (a chorismate-derived product), aroA (EPSPS) was tuned among shikimate-pathway genes; reducing aroA expression to native levels lowered product titer, indicating aroA expression contributes to aromatic-pathway flux in vivo.
reference_section_type: RESULTS
reference_review:
relevance: MEDIUM
correctness: VERIFIED
review_notes: >-
PMID confirmed via PubMed search (single match to title keywords +
organism). KT2440-specific engineering study; supports aroA as a
flux-relevant shikimate-pathway node rather than providing direct
purified-enzyme kinetics. Surfaced through the falcon deep-research summary.
suggested_questions:
- question: Is the prephenate dehydrogenase (TyrA) module of P. putida AroA catalytically active in vivo, and does it prefer NAD+ or NADP+ as cofactor?
- question: Does the AroA-TyrA domain fusion form a substrate channel or otherwise functionally couple chorismate biosynthesis with the tyrosine branch in P. putida?
suggested_experiments:
- description: Heterologously express and purify Q88M05 and assay both EPSP synthase (S3P + PEP) and prephenate dehydrogenase (prephenate + NAD+/NADP+) activities to confirm bifunctionality and determine cofactor preference.
- description: Construct an aroA deletion/complementation in P. putida KT2440 and test for aromatic amino acid (and specifically tyrosine) auxotrophy to establish in vivo requirement of each catalytic module.