id: Q86YB8
gene_symbol: ERO1B
product_type: PROTEIN
status: COMPLETE
taxon:
  id: NCBITaxon:9606
  label: Homo sapiens
description: ERO1B (ERO1-like protein beta, formerly ERO1LB; endoplasmic reticulum oxidoreductin-1 beta) is an ER membrane-associated, FAD-dependent flavoprotein sulfhydryl oxidase (EC 1.8.3.2) and a paralog of ERO1A. It drives oxidative protein folding in the endoplasmic reticulum by reoxidizing the protein disulfide isomerase P4HB/PDI (and, less efficiently, other PDI-family members), regenerating their active-site disulfides so they can catalyze further disulfide-bond formation in secretory proteins; the abstracted electrons are passed via bound FAD to molecular oxygen, producing hydrogen peroxide. It is a peripheral membrane protein on the lumenal side of the ER (and is retained there in part through interaction with ERP44), and forms disulfide-linked homodimers as well as heterodimers with ERO1A. Compared with ERO1A it is intrinsically more active and more loosely regulated, consistent with its enrichment in professional secretory tissues - particularly the pancreatic islets of Langerhans, stomach chief cells and digestive tract - where high oxidative folding capacity is required. It is induced during the unfolded protein response and has been implicated in oxidative proinsulin folding and glucose homeostasis.
existing_annotations:
- term:
    id: GO:0005789
    label: endoplasmic reticulum membrane
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: is_active_in
  review:
    summary: ERO1B is a peripheral ER membrane protein on the lumenal side; this is its primary site of action, supported experimentally and by phylogenetic inference.
    action: ACCEPT
    reason: The ER membrane (lumenal side) is the documented site where ERO1B reoxidizes PDI; corroborated by direct subcellular-location evidence.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: 'SUBCELLULAR LOCATION: Endoplasmic reticulum membrane'
- term:
    id: GO:0005783
    label: endoplasmic reticulum
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: located_in
  review:
    summary: ER localization is correct and the principal compartment for ERO1B.
    action: ACCEPT
    reason: ERO1B is an ER-resident oxidase; directly supported by immunofluorescence and glycosylation evidence.
    supported_by:
    - reference_id: PMID:10818100
      supporting_text: the products of the ERO1-Lbeta gene are primarily localized in the ER of mammalian cells
- term:
    id: GO:0005789
    label: endoplasmic reticulum membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: Electronic ER-membrane localization, consistent with experimental and IBA evidence.
    action: ACCEPT
    reason: Correct compartment; ERO1B is a peripheral ER membrane protein.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: Peripheral membrane protein
- term:
    id: GO:0015035
    label: protein-disulfide reductase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: enables
  review:
    summary: This term asserts a disulfide REDUCTASE activity. ERO1B is mechanistically an OXIDASE that reoxidizes (forms disulfides in) PDI; the reductase label misrepresents the catalytic direction.
    action: MARK_AS_OVER_ANNOTATED
    reason: ERO1B oxidizes PDI and passes electrons to O2 generating H2O2; the physiological direction is dithiol oxidation, not disulfide reduction, so a reductase annotation is an over-annotation.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: Efficiently reoxidizes P4HB/PDI, the enzyme catalyzing protein disulfide formation, in order to allow P4HB to sustain additional rounds of disulfide formation.
- term:
    id: GO:0016971
    label: flavin-dependent sulfhydryl oxidase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000116
  qualifier: enables
  review:
    summary: This is the precise core molecular function of ERO1B - a FAD-dependent sulfhydryl oxidase catalyzing dithiol + O2 = disulfide + H2O2 (RHEA:59116).
    action: ACCEPT
    reason: Matches the catalytic activity and FAD cofactor of ERO1B; supported by EXP evidence (PMID:11707400, PMID:21091435).
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: 'Reaction=[protein]-dithiol + O2 = [protein]-disulfide + H2O2'
- term:
    id: GO:0016972
    label: thiol oxidase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: enables
  review:
    summary: Thiol oxidase activity is the broader parent of ERO1B's flavin-dependent sulfhydryl oxidase activity; correct but less specific.
    action: ACCEPT
    reason: Correctly captures ERO1B's oxidase activity; the EXP/IDA versions of the same term confirm it.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: 'EC=1.8.3.2'
- term:
    id: GO:0034975
    label: protein folding in endoplasmic reticulum
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: involved_in
  review:
    summary: ERO1B drives oxidative protein folding in the ER; this is a valid downstream process outcome of its oxidase activity.
    action: KEEP_AS_NON_CORE
    reason: Protein folding in the ER is the biological-process consequence of the oxidase activity rather than ERO1B's direct molecular function.
    supported_by:
    - reference_id: PMID:21091435
      supporting_text: drives oxidative protein folding
- term:
    id: GO:0071949
    label: FAD binding
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: enables
  review:
    summary: ERO1B is a flavoprotein that binds FAD as its cofactor.
    action: ACCEPT
    reason: FAD is the documented cofactor (PMID:21091435), integral to the oxidase mechanism; FAD binding residues are mapped.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: 'Name=FAD; Xref=ChEBI:CHEBI:57692'
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:20802462
  qualifier: enables
  review:
    summary: IntAct interaction with PDIA3/ERp57 (P30101). The bare protein binding term is uninformative; it records an interaction within the ER oxidoreductase network.
    action: KEEP_AS_NON_CORE
    reason: Records a real physical interaction (PDIA3), but the generic protein binding term is uninformative and the informative function is the oxidase MF; ERO1B's principal PDI substrate is P4HB.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: 'Q86YB8; P30101: PDIA3'
- term:
    id: GO:0005788
    label: endoplasmic reticulum lumen
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: is_active_in
  review:
    summary: ERO1B acts on the lumenal side of the ER membrane; ER lumen is consistent with its site of action.
    action: ACCEPT
    reason: ERO1B is a lumenal-side ER protein; ER lumen localization is consistent with its function.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: Lumenal side
- term:
    id: GO:0015036
    label: disulfide oxidoreductase activity
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: enables
  review:
    summary: A directionless parent term for thiol-disulfide oxidoreduction; correctly captures ERO1B's catalytic chemistry without mislabeling it as a reductase.
    action: ACCEPT
    reason: Accurate (direction-neutral) molecular-function term for an enzyme that interconverts dithiols and disulfides on PDI; subsumed by the more specific sulfhydryl oxidase term.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: Oxidoreductase involved in disulfide bond formation in the endoplasmic reticulum.
- term:
    id: GO:0016020
    label: membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000107
  qualifier: located_in
  review:
    summary: Generic membrane localization; ERO1B is a peripheral membrane protein, so this is consistent but uninformative.
    action: KEEP_AS_NON_CORE
    reason: Correct but generic; the specific ER membrane term is preferred.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: Peripheral membrane protein
- term:
    id: GO:0030070
    label: insulin processing
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-264876
  qualifier: involved_in
  review:
    summary: ERO1B may drive oxidative proinsulin folding in pancreatic beta cells, contributing to insulin processing; a genuine but specialized, tissue-restricted role. Recent proteomic work corroborates ERO1B enrichment in beta cells and its association with insulin biogenesis.
    action: KEEP_AS_NON_CORE
    reason: Supported as a plausible specialized function in pancreatic islets (where ERO1B is enriched), but it is a tissue-specific downstream role rather than the core oxidase function. The falcon deep research synthesizes recent proteomic data (axelsson2024) identifying ERO1B as enriched in pancreatic beta cells and implicated in insulin biogenesis, consistent with this annotation; this remains a specialized downstream process rather than the core MF.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: May be involved in oxidative proinsulin folding in pancreatic cells, hence may play a role in glucose homeostasis.
    - reference_id: file:human/ERO1B/ERO1B-deep-research-falcon.md
      supporting_text: ERO1B plays a specialized role in supporting the high protein secretory load of pancreatic beta cells, particularly for the folding and maturation of proinsulin
    - reference_id: file:human/ERO1B/ERO1B-deep-research-falcon.md
      supporting_text: Single-cell proteomics of human pancreatic islet cells found that ERO1B expression was higher in beta cells
- term:
    id: GO:0016971
    label: flavin-dependent sulfhydryl oxidase activity
  evidence_type: EXP
  original_reference_id: PMID:11707400
  qualifier: enables
  review:
    summary: Experimentally supported FAD-dependent sulfhydryl oxidase activity - ERO1B facilitates disulfide bond formation by oxidizing PDI.
    action: ACCEPT
    reason: Direct experimental evidence (selective oxidation of PDI); core molecular function.
    supported_by:
    - reference_id: PMID:11707400
      supporting_text: both human Ero1-Lalpha and Ero1-Lbeta (hEROs) facilitate disulfide bond formation in immunoglobulin subunits by selectively oxidizing PDI
- term:
    id: GO:0016971
    label: flavin-dependent sulfhydryl oxidase activity
  evidence_type: EXP
  original_reference_id: PMID:21091435
  qualifier: enables
  review:
    summary: Experimentally supported FAD-dependent sulfhydryl oxidase activity; recombinant ERO1B is twice as active as ERO1A and oxidizes PDI efficiently. ERO1B acts on PDI (not client proteins directly) via a two-step ERO1-PDI relay.
    action: ACCEPT
    reason: Direct enzymatic-assay evidence for the core oxidase function; ERO1B is a highly active, loosely regulated oxidase. The falcon deep research reinforces that ERO1B's catalytic substrate is reduced PDI, which it re-oxidizes so PDI can in turn introduce disulfide bonds into nascent secretory proteins.
    supported_by:
    - reference_id: PMID:21091435
      supporting_text: recombinant human Ero1β is twice as active as Ero1α in enzymatic assays
    - reference_id: file:human/ERO1B/ERO1B-deep-research-falcon.md
      supporting_text: 'ERO1B does not directly oxidize client secretory proteins; instead, it functions in a two-step relay system'
- term:
    id: GO:0016972
    label: thiol oxidase activity
  evidence_type: EXP
  original_reference_id: PMID:11707400
  qualifier: enables
  review:
    summary: Experimentally supported thiol oxidase activity (parent of the flavin-dependent sulfhydryl oxidase term).
    action: ACCEPT
    reason: EXP evidence for oxidase activity; correct core function, though the flavin-dependent sulfhydryl oxidase term is the most precise.
    supported_by:
    - reference_id: PMID:11707400
      supporting_text: both human Ero1-Lalpha and Ero1-Lbeta (hEROs) facilitate disulfide bond formation in immunoglobulin subunits by selectively oxidizing PDI
- term:
    id: GO:0005788
    label: endoplasmic reticulum lumen
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9817575
  qualifier: located_in
  review:
    summary: Reactome ER-lumen localization, consistent with ERO1B's lumenal-side site of action.
    action: ACCEPT
    reason: Consistent with the documented lumenal-side ER localization.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: Lumenal side
- term:
    id: GO:0015035
    label: protein-disulfide reductase activity
  evidence_type: EXP
  original_reference_id: PMID:11707400
  qualifier: enables
  review:
    summary: This Reactome EXP annotation labels ERO1B as a protein-disulfide REDUCTASE. ERO1B physically engages PDI active-site disulfides, but its physiological action is oxidation of PDI (forming disulfides), not reduction; the reductase label is directionally misleading.
    action: MARK_AS_OVER_ANNOTATED
    reason: The supporting study shows ERO1B/ERO1 oxidizes PDI; the reductase directionality mischaracterizes the enzyme, which is an oxidase. The accurate term is sulfhydryl oxidase / disulfide oxidoreductase activity.
    supported_by:
    - reference_id: PMID:11707400
      supporting_text: both human Ero1-Lalpha and Ero1-Lbeta (hEROs) facilitate disulfide bond formation in immunoglobulin subunits by selectively oxidizing PDI
- term:
    id: GO:0015035
    label: protein-disulfide reductase activity
  evidence_type: EXP
  original_reference_id: PMID:16407158
  qualifier: enables
  review:
    summary: Reactome EXP reductase annotation. As above, the ERO1 enzyme generates disulfides (oxidase); the reductase directionality is misleading.
    action: MARK_AS_OVER_ANNOTATED
    reason: The cited work concerns enzymatic disulfide generation by the ER thiol oxidase Ero1; an oxidase, not a reductase. The reductase term over-annotates the catalytic direction.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: Following P4HB reoxidation, passes its electrons to molecular oxygen via FAD
- term:
    id: GO:0015035
    label: protein-disulfide reductase activity
  evidence_type: EXP
  original_reference_id: PMID:21091435
  qualifier: enables
  review:
    summary: Reactome EXP reductase annotation derived from the Ero1β characterization, which actually shows ERO1B oxidizes PDI; the reductase directionality is misleading.
    action: MARK_AS_OVER_ANNOTATED
    reason: The supporting study demonstrates oxidase activity (oxidizing PDI), not disulfide reduction; the reductase term mislabels the catalytic direction.
    supported_by:
    - reference_id: PMID:21091435
      supporting_text: Ero1β oxidizes PDI more efficiently than other PDI family members
- term:
    id: GO:0034975
    label: protein folding in endoplasmic reticulum
  evidence_type: IDA
  original_reference_id: PMID:21091435
  qualifier: involved_in
  review:
    summary: ERO1B drives oxidative protein folding in the ER; protein folding in the ER is a downstream process of its oxidase activity.
    action: KEEP_AS_NON_CORE
    reason: A valid process annotation supported by direct evidence, but downstream of the core oxidase molecular function.
    supported_by:
    - reference_id: PMID:21091435
      supporting_text: drives oxidative protein folding
- term:
    id: GO:0016972
    label: thiol oxidase activity
  evidence_type: IDA
  original_reference_id: PMID:21091435
  qualifier: enables
  review:
    summary: Direct-assay thiol oxidase activity confirmed for recombinant ERO1B.
    action: ACCEPT
    reason: IDA evidence for the core oxidase activity from enzymatic assays.
    supported_by:
    - reference_id: PMID:21091435
      supporting_text: recombinant human Ero1β is twice as active as Ero1α in enzymatic assays
- term:
    id: GO:0005783
    label: endoplasmic reticulum
  evidence_type: TAS
  original_reference_id: PMID:10818100
  qualifier: located_in
  review:
    summary: ERO1-Lbeta is primarily localized in the ER (immunofluorescence, endoglycosidase sensitivity, in vitro translocation).
    action: ACCEPT
    reason: TAS from the founding characterization directly establishes ER localization.
    supported_by:
    - reference_id: PMID:10818100
      supporting_text: the products of the ERO1-Lbeta gene are primarily localized in the ER of mammalian cells
- term:
    id: GO:0006457
    label: protein folding
  evidence_type: TAS
  original_reference_id: PMID:10818100
  qualifier: involved_in
  review:
    summary: ERO1-Lbeta generates oxidative conditions in the ER required for disulfide bond formation; protein folding is the downstream process.
    action: KEEP_AS_NON_CORE
    reason: A valid process annotation but downstream of the core oxidase molecular function.
    supported_by:
    - reference_id: PMID:10818100
      supporting_text: ERO1-Lbeta is involved also in generating oxidative conditions in the ER
- term:
    id: GO:0016491
    label: oxidoreductase activity
  evidence_type: NAS
  original_reference_id: PMID:10818100
  qualifier: enables
  review:
    summary: ERO1B is an oxidoreductase; a correct but very general parent term.
    action: ACCEPT
    reason: Correct high-level molecular function, subsumed by the more specific flavin-dependent sulfhydryl oxidase activity.
    supported_by:
    - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
      supporting_text: Oxidoreductase involved in disulfide bond formation in the endoplasmic reticulum.
references:
- id: GO_REF:0000002
  title: Gene Ontology annotation through association of InterPro records with GO terms
  findings: []
- id: GO_REF:0000033
  title: Annotation inferences using phylogenetic trees
  findings: []
- id: GO_REF:0000044
  title: Gene Ontology annotation based on UniProtKB Subcellular Location vocabulary mapping
  findings: []
- id: GO_REF:0000107
  title: Automatic transfer of experimentally verified manual GO annotation data to orthologs using Ensembl Compara
  findings: []
- id: GO_REF:0000116
  title: Gene Ontology annotation based on RHEA mapping of reactions
  findings: []
- id: GO_REF:0000120
  title: Combined Automated Annotation using Multiple IEA Methods
  findings: []
- id: PMID:10818100
  title: Endoplasmic reticulum oxidoreductin 1-lbeta (ERO1-Lbeta), a human gene induced in the course of the unfolded protein response.
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: "Cached publications/PMID_10818100.md title matches YAML; original identification of ERO1B as an ER oxidoreductin generating oxidative ER conditions. GOA anchors this PMID to ER localization (GO:0005783) and protein folding (GO:0006457)."
  findings:
  - statement: ERO1-Lbeta is a human EROs-family gene primarily localized to the ER, able to generate oxidative conditions in the ER (complementing the yeast ero1-1 mutant), with a distinct tissue distribution from ERO1-L and uniquely induced during the unfolded protein response.
    reference_section_type: ABSTRACT
- id: PMID:11707400
  title: Manipulation of oxidative protein folding and PDI redox state in mammalian cells.
  findings:
  - statement: Both human Ero1-Lalpha and Ero1-Lbeta facilitate disulfide bond formation in immunoglobulin subunits by selectively oxidizing PDI.
    reference_section_type: ABSTRACT
- id: PMID:16407158
  title: 'Generating disulfides enzymatically: reaction products and electron acceptors of the endoplasmic reticulum thiol oxidase Ero1p.'
  findings:
  - statement: Characterizes the ER thiol oxidase Ero1 mechanism of enzymatic disulfide generation and electron acceptors (oxidase chemistry).
    reference_section_type: ABSTRACT
- id: PMID:20802462
  title: Disulphide production by Ero1α-PDI relay is rapid and effectively regulated.
  findings: []
- id: PMID:21091435
  title: The endoplasmic reticulum sulfhydryl oxidase Ero1β drives efficient oxidative protein folding with loose regulation.
  reference_review:
    relevance: HIGH
    correctness: VERIFIED
    review_notes: "Cached publications/PMID_21091435.md title matches YAML; biochemically establishes the core MF — recombinant Ero1β is a sulfhydryl oxidase that oxidizes PDI and drives oxidative folding. GOA anchors this PMID to GO:0016971/GO:0016972 (flavin-dependent sulfhydryl oxidase, EXP/IDA) and GO:0015035."
  findings:
  - statement: Recombinant human Ero1β is twice as active as Ero1α, oxidizes PDI more efficiently than other PDI family members, drives oxidative protein folding preferentially via the a domain of PDI, and is loosely regulated (Cys130 critical for feedback); it is constitutively expressed in professional secretory tissues and UPR-induced.
    reference_section_type: ABSTRACT
- id: Reactome:R-HSA-264876
  title: Insulin processing
  findings: []
- id: Reactome:R-HSA-9817575
  title: Reactome ER-lumen oxidative folding annotation for ERO1B
  findings: []
- id: file:human/ERO1B/ERO1B-uniprot.txt
  title: UniProt entry Q86YB8 (ERO1B_HUMAN), ERO1-like protein beta
  findings:
  - statement: FAD-dependent ER sulfhydryl oxidase (EC 1.8.3.2) that reoxidizes P4HB/PDI (and other PDI-family members at lower rates) to drive disulfide-bond formation, passing electrons to O2 via FAD; peripheral lumenal-side ER membrane protein, homodimeric and heterodimeric with ERO1A; enriched in pancreatic islets and digestive tract; UPR-induced; implicated in proinsulin folding/glucose homeostasis.
    reference_section_type: OTHER
- id: file:human/ERO1B/ERO1B-deep-research-falcon.md
  title: Falcon deep research report for ERO1B
  reference_review:
    relevance: MEDIUM
    correctness: UNVERIFIED
    review_notes: "LLM-synthesized (Edison/Falcon) report. Useful corroboration on several
      points: it correctly frames ERO1B as acting via a two-step ERO1-PDI relay (it
      oxidizes PDI rather than client proteins directly) and reiterates ER-lumen
      localization, redox-regulated activity, H2O2 production, and PRDX4/GPX7/GPX8
      functional redundancy. The ERO1B-SPECIFIC claims that are genuinely supported are
      the preferential expression in secretory tissues/pancreatic beta cells and the
      proteomic association with insulin biogenesis (axelsson2024 proteomic/islet
      single-cell data). MANY mechanistic statements (regulatory-disulfide residue
      numbering Cys94-Cys131/Cys99-Cys104, ~25% of translational H2O2, regulatory
      switch behavior) are explicitly generalized from ERO1A 'by extension' and are NOT
      independently demonstrated for ERO1B; these are treated as ERO1A-derived
      inferences and not used to alter annotations. Primary-literature DOIs cited in the
      report (e.g. zito2024, axelsson2024) were not individually re-verified here, hence
      UNVERIFIED."
core_functions:
- description: FAD-dependent endoplasmic-reticulum sulfhydryl oxidase that reoxidizes the protein disulfide isomerase P4HB/PDI, regenerating PDI's active site to sustain disulfide-bond formation in secretory proteins, with electrons passed via FAD to O2 producing H2O2; intrinsically more active and more loosely regulated than ERO1A.
  molecular_function:
    id: GO:0016971
    label: flavin-dependent sulfhydryl oxidase activity
  locations:
  - id: GO:0005789
    label: endoplasmic reticulum membrane
  - id: GO:0005788
    label: endoplasmic reticulum lumen
  supported_by:
  - reference_id: file:human/ERO1B/ERO1B-uniprot.txt
    supporting_text: Efficiently reoxidizes P4HB/PDI, the enzyme catalyzing protein disulfide formation, in order to allow P4HB to sustain additional rounds of disulfide formation.
  - reference_id: PMID:21091435
    supporting_text: recombinant human Ero1β is twice as active as Ero1α in enzymatic assays
proposed_new_terms: []
suggested_questions:
- question: How is the division of labor between ERO1B and ERO1A (and PRDX4) established in pancreatic beta cells, and how essential is ERO1B specifically for proinsulin oxidative folding and insulin secretion?
- question: Does the looser regulation of ERO1B relative to ERO1A make secretory tissues more vulnerable to ER oxidative stress, and how is its activity feedback-controlled in vivo?
suggested_experiments:
- description: Beta-cell-specific knockout or knockdown of ERO1B (alone and combined with ERO1A) followed by assays of proinsulin folding, insulin secretion and ER redox state to test its role in glucose homeostasis.
- description: Comparative enzymology of purified ERO1B versus ERO1A measuring O2 consumption, H2O2 production and PDI-isoform substrate preference, including the regulatory-disulfide mutants (e.g. Cys130) that govern feedback control.