Candida albicans ALO1 encodes an FAD-linked sugar-lactone oxidase of the fungal ALO1 family. The enzyme is purified from mitochondrial fractions, is predicted to be an integral membrane protein, and catalyzes the terminal oxidation of D-arabinono-1,4-lactone in D-erythroascorbic acid biosynthesis. Loss of ALO1 abolishes cellular D-arabinono-1,4-lactone oxidase activity and D-erythroascorbic acid production, making cells more sensitive to oxidative stress and conditionally reducing filamentous growth and virulence.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0003885 D-arabinono-1,4-lactone oxidase activity | IBA GO_REF:0000033 | ACCEPT | Summary: The PTN000356435 IBA correctly propagates the exact fungal ALO1 D-arabinono-1,4-lactone oxidase activity. Reason: PTN000356435 is seeded by characterized C. albicans and S. cerevisiae ALO1 proteins and sits on the ALO1 branch before the curated Candida member, so this IBA is the PAINT curator's direct ancestral placement of the same EC 1.1.3.37 activity established biochemically for ALO1. Propagation Review Root cause: NO FAILURE CORE Sources checked: PANTHER:PTN000356435 · PANTHER:PTN000356435 SUPPORTS TRANSFER This PAINT node carries the EC 1.1.3.37 activity for the ALO1 branch and is seeded by experimentally characterized Candida and budding yeast ALO1 proteins. Supporting Evidence: file:interpro/panther/PTHR43762/PTHR43762-paint.tsv PTHR43762 PTN000356435 GO:0003885 F IBD false PMID:7957197 D-Arabinono-1,4-lactone oxidase, which catalyses the final step in the biosynthesis of D-erythroascorbic acid |
| GO:0003885 D-arabinono-1,4-lactone oxidase activity | IDA PMID:7957197 Characterisation of D-arabinono-1,4-lactone oxidase from Can... | ACCEPT | Summary: The purified C. albicans enzyme directly supports D-arabinono-1,4-lactone oxidase activity. Reason: Huh et al. purified D-arabinono-1,4-lactone oxidase from the mitochondrial fraction of C. albicans and characterized the exact substrate oxidase activity later assigned to ALO1. Supporting Evidence: PMID:7957197 D-Arabinono-1,4-lactone oxidase, which catalyses the final step in the biosynthesis of D-erythroascorbic acid, was purified 639-fold from the mitochondrial fraction of C. albicans |
| GO:0003885 D-arabinono-1,4-lactone oxidase activity | IEA GO_REF:0000120 | ACCEPT | Summary: The combined UniProt, Rhea, EC, and InterPro prediction matches the exact experimentally demonstrated ALO1 activity. Reason: The electronic assertion uses the exact EC 1.1.3.37/RHEA:23756 reaction, the same ALO_C domain architecture, and the S. cerevisiae ALO1 ortholog; all agree with direct C. albicans enzymology and with the PAINT IBA. Supporting Evidence: file:genes/CANAL/ALO1/ALO1-uniprot.txt EC=1.1.3.37 {ECO:0000269|PubMed:7957197} PMID:7957197 D-Arabinono-1,4-lactone oxidase, which catalyses the final step in the biosynthesis of D-erythroascorbic acid |
| GO:0005739 mitochondrion | IBA GO_REF:0000033 | ACCEPT | Summary: The PTN001015900 IBA soundly transfers broad mitochondrial localization across the Dikarya ALO1 branch. Reason: PAINT places only the broad mitochondrial component at PTN001015900. That scope is consistent with the Candida enzyme's purification from a mitochondrial fraction and avoids over-propagating the more specific S. cerevisiae outer-membrane-side claim. Propagation Review Root cause: NO FAILURE CORE Sources checked: PANTHER:PTN001015900 · PANTHER:PTN001015900 SUPPORTS TRANSFER This PAINT node propagates the experimentally supported broad mitochondrion component rather than the narrower S. cerevisiae mitochondrial outer membrane side. Supporting Evidence: file:interpro/panther/PTHR43762/PTHR43762-paint.tsv PTHR43762 PTN001015900 GO:0005739 C IBD false PMID:7957197 was purified 639-fold from the mitochondrial fraction of C. albicans |
| GO:0005739 mitochondrion | IDA PMID:7957197 Characterisation of D-arabinono-1,4-lactone oxidase from Can... | ACCEPT | Summary: Purification from the C. albicans mitochondrial fraction directly supports the broad mitochondrion component. Reason: The 1994 enzymology purified the oxidase from the mitochondrial fraction, which is direct evidence for the broad component even though it does not resolve the outer versus inner mitochondrial membrane. Supporting Evidence: PMID:7957197 was purified 639-fold from the mitochondrial fraction of C. albicans |
| GO:0005739 mitochondrion | IEA GO_REF:0000120 | ACCEPT | Summary: The automated broad mitochondrial assignment agrees with Candida purification data and with PAINT. Reason: Broad mitochondrial localization is the right electronic target for this orthologous ALO1 enzyme, because C. albicans ALO was purified from mitochondrial fractions and PAINT propagates the same broad component. Supporting Evidence: PMID:7957197 was purified 639-fold from the mitochondrial fraction of C. albicans file:interpro/panther/PTHR43762/PTHR43762-paint.tsv PTHR43762 PTN001015900 GO:0005739 C IBD false |
| GO:0005741 mitochondrial outer membrane | IEA GO_REF:0000107 | MODIFY | Summary: The SGD-derived outer-membrane transfer is too specific for the experimentally demonstrated C. albicans localization. Reason: C. albicans evidence places ALO1 in the mitochondrial fraction and its sequence predicts an integral membrane protein, but neither the direct Candida work nor PAINT establishes the outer mitochondrial membrane specifically. The row should be generalized to mitochondrial membrane. Proposed replacements: mitochondrial membrane Supporting Evidence: PMID:7957197 was purified 639-fold from the mitochondrial fraction of C. albicans PMID:11349062 predicted that the enzyme should be an integral membrane protein with a transmembrane segment |
| GO:0005886 plasma membrane | IDA PMID:19824013 Analysis of Candida albicans plasma membrane proteome. | UNDECIDED | Summary: The ALO1-specific plasma-membrane proteomics evidence is not visible in the cached abstract-only record. Reason: The supporting publication describes a large C. albicans plasma-membrane proteome, but the cache lacks the full text or supplemental peptide list needed to verify that ALO1 was identified rather than present as a mitochondrial contaminant. Defer to the CGD IDA until the full data table can be inspected. Supporting Evidence: PMID:19824013 A subproteomic approach to obtain a global picture of the protein composition of the C. albicans plasma membrane was developed |
| GO:0009267 cellular response to starvation | IMP PMID:11349062 Deficiency of D-erythroascorbic acid attenuates hyphal growt... | KEEP AS NON CORE | Summary: ALO1 loss conditionally affects starvation-medium hyphal growth, a physiological phenotype downstream of erythroascorbate biosynthesis. Reason: Full-text Candida work found reduced filamentation on solid Spider medium and corn meal agar but little difference in other liquid and solid hyphal induction media. This supports a starvation-associated phenotype without making starvation response the core function of the mitochondrial oxidase. Supporting Evidence: PMID:11349062 in spite of the defective hyphal growth of WH203 on solid Spider medium and corn meal agar, the mutant strain exhibited hyphal growth patterns little different from SC5314 in other liquid and solid media |
| GO:0016020 membrane | IEA GO_REF:0000120 | MODIFY | Summary: The ALO_C membrane prediction is correct but should be made more informative as mitochondrial membrane. Reason: The InterPro membrane assertion captures the predicted transmembrane ALO_C oxidase, and the Candida enzyme was purified from mitochondrial fractions. General mitochondrial membrane is therefore better supported than bare membrane while avoiding an unsupported outer-membrane-side claim. Proposed replacements: mitochondrial membrane Supporting Evidence: PMID:11349062 predicted that the enzyme should be an integral membrane protein with a transmembrane segment PMID:7957197 was purified 639-fold from the mitochondrial fraction of C. albicans |
| GO:0016491 oxidoreductase activity | IEA GO_REF:0000002 | MODIFY | Summary: The InterPro oxidoreductase call is true but too generic for the exact EC 1.1.3.37 ALO1 enzyme. Reason: C. albicans ALO1 is a D-arabinono-1,4-lactone oxidase, not just a generic FAD oxidoreductase, so the exact child activity already present in PAINT, CGD, and Rhea is the appropriate replacement. Proposed replacements: D-arabinono-1,4-lactone oxidase activity Supporting Evidence: PMID:7957197 D-Arabinono-1,4-lactone oxidase, which catalyses the final step in the biosynthesis of D-erythroascorbic acid |
| GO:0016899 oxidoreductase activity, acting on the CH-OH group of donors, oxygen as acceptor | IEA GO_REF:0000002 | MODIFY | Summary: The FAD lactone oxidase InterPro term is directionally correct but less specific than D-arabinono-1,4-lactone oxidase activity. Reason: ALO1 was experimentally characterized as an oxygen-dependent D-arabinono-1,4-lactone oxidase; GO:0003885 captures the same chemical activity more exactly than its broad GO:0016899 parent. Proposed replacements: D-arabinono-1,4-lactone oxidase activity Supporting Evidence: PMID:7957197 D-Arabinono-1,4-lactone oxidase, which catalyses the final step in the biosynthesis of D-erythroascorbic acid |
| GO:0030447 filamentous growth | IMP PMID:11349062 Deficiency of D-erythroascorbic acid attenuates hyphal growt... | KEEP AS NON CORE | Summary: ALO1 contributes to C. albicans filamentation on specific solid hyphal media as a downstream physiological role. Reason: alo1/alo1 cells had defective hyphal growth on solid Spider medium and corn meal agar, and reintegration restored extensive hyphae. The defect was conditional, so this is a real non-core phenotype of losing erythroascorbate biosynthesis. Supporting Evidence: PMID:11349062 The Ura + alo1/alo1 strain WH203 showed little hyphal formation compared with SC5314. The hyphal growth of the ALO1 reintegrant strain WH207 was similar to that of WH201 |
| GO:0031489 myosin V binding | IEA GO_REF:0000107 | REMOVE | Summary: The S. cerevisiae Myo2 binding claim should not be transferred to Candida ALO1 from shared ALO oxidase domains. Reason: The Myo2 interaction was found in budding yeast as a mitochondrial inheritance link between Alo1 and the Myo2 cargo-binding domain. It is a species-specific interaction claim rather than a biochemical property of the conserved FAD-linked ALO fold, and no C. albicans evidence found here supports a Myosin V binding activity for ALO1. Supporting Evidence: PMID:39775849 using the cargo-binding domain of Myo2, the major organelle transporter in yeast, as bait and a genome-wide strain collection expressing yeast proteins as prey file:genes/CANAL/ALO1/ALO1-uniprot.txt DR InterPro; IPR007173; ALO_C. |
| GO:0032473 cytoplasmic side of mitochondrial outer membrane | IEA GO_REF:0000107 | MODIFY | Summary: The cytoplasmic face of the outer mitochondrial membrane is over-specific for Candida ALO1 localization. Reason: The C. albicans enzyme is mitochondrial and predicted to be membrane embedded, but neither the Candida purification paper nor the PAINT component node establishes the cytoplasmic side of the outer mitochondrial membrane. General mitochondrial membrane is the supported replacement. Proposed replacements: mitochondrial membrane Supporting Evidence: PMID:7957197 was purified 639-fold from the mitochondrial fraction of C. albicans PMID:11349062 predicted that the enzyme should be an integral membrane protein with a transmembrane segment |
| GO:0034599 cellular response to oxidative stress | IEA GO_REF:0000120 | KEEP AS NON CORE | Summary: The electronic oxidative-stress assertion is supported as a conserved physiological consequence of fungal ALO1 activity. Reason: Candida alo1/alo1 cells are hypersensitive to oxidants and ALO1 overexpression increases resistance, consistent with a fungal erythroascorbate antioxidant role. The process is retained as non-core because ALO1 directly catalyzes erythroascorbate biosynthesis. Supporting Evidence: PMID:11349062 The alo1/alo1 null mutants of C. albicans showed increased sensitivity towards oxidative stress |
| GO:0034599 cellular response to oxidative stress | IMP PMID:11349062 Deficiency of D-erythroascorbic acid attenuates hyphal growt... | KEEP AS NON CORE | Summary: The direct Candida mutant and overexpression phenotypes show that ALO1 supports oxidative-stress resistance. Reason: Disrupting ALO1 eliminated D-erythroascorbate and increased H2O2 and menadione sensitivity, while ALO1 overexpression increased survival under the same oxidants. This is a well-supported physiological outcome of the oxidase activity, not a separate core molecular function. Supporting Evidence: PMID:11349062 The alo1/alo1 null mutants of C. albicans showed increased sensitivity towards oxidative stress. Overexpression of ALO1 made the cells more resistant to the same stress |
| GO:0036170 filamentous growth of a population of unicellular organisms in response to starvation | IMP PMID:11349062 Deficiency of D-erythroascorbic acid attenuates hyphal growt... | KEEP AS NON CORE | Summary: ALO1 supports filamentous growth on starvation-associated solid media, but this is a conditional non-core phenotype. Reason: alo1/alo1 mutants showed little hyphal formation on solid Spider medium and similar results on corn meal agar, while showing near-normal hyphal growth in several other hyphal-induction conditions. The annotation is therefore kept as a non-core conditional phenotype. Supporting Evidence: PMID:11349062 Growth on corn meal agar gave similar results PMID:11349062 the mutant strain exhibited hyphal growth patterns little different from SC5314 in other liquid and solid media |
| GO:0044182 filamentous growth of a population of unicellular organisms | IMP PMID:11349062 Deficiency of D-erythroascorbic acid attenuates hyphal growt... | KEEP AS NON CORE | Summary: The broad filamentous-growth phenotype is supported, but conditional and downstream of D-erythroascorbate production. Reason: ALO1 is needed for efficient hyphal formation on some solid hyphal media, with reintegration restoring extensive hyphae, but the authors emphasized that D-erythroascorbate was not required for hyphal growth under every inducing condition. Supporting Evidence: PMID:11349062 These results indicate that EASC contributes to the hyphal growth of C. albicans PMID:11349062 EASC is not needed for hyphal growth of C. albicans under all inducing conditions |
| GO:0050024 L-galactonolactone oxidase activity | EXP PMID:7957197 Characterisation of D-arabinono-1,4-lactone oxidase from Can... | KEEP AS NON CORE | Summary: Purified C. albicans ALO can oxidize L-galactono-1,4-lactone in vitro, but this is secondary substrate usage. Reason: Direct enzymology showed that L-galactono-1,4-lactone can serve as a substrate for the purified enzyme. D-arabinono-1,4-lactone is the physiological substrate in fungal erythroascorbate biosynthesis, so the L-galactonolactone activity is real but non-core. Supporting Evidence: PMID:7957197 L-Galactono-1,4-lactone, L-gulono-1,4-lactone and L-xylono-1,4-lactone could also serve as substrates. |
| GO:0050024 L-galactonolactone oxidase activity | IEA GO_REF:0000120 | KEEP AS NON CORE | Summary: The Rhea/EC L-galactonolactone oxidase mapping is experimentally grounded but secondary for C. albicans ALO1. Reason: UniProt's EC 1.3.3.12 assignment comes from the same purified-enzyme substrate panel that found L-galactono-1,4-lactone was accepted in vitro. It is less central than the physiological EC 1.1.3.37 reaction. Supporting Evidence: file:genes/CANAL/ALO1/ALO1-uniprot.txt EC=1.3.3.12 {ECO:0000269|PubMed:7957197} PMID:7957197 L-Galactono-1,4-lactone, L-gulono-1,4-lactone and L-xylono-1,4-lactone could also serve as substrates. |
| GO:0050105 L-gulonolactone oxidase activity | EXP PMID:7957197 Characterisation of D-arabinono-1,4-lactone oxidase from Can... | KEEP AS NON CORE | Summary: Purified C. albicans ALO can oxidize L-gulono-1,4-lactone in vitro, but this is a non-core substrate activity. Reason: The purified enzyme used L-gulono-1,4-lactone as one of several alternate lactone substrates. D-arabinono-1,4-lactone remains the physiological substrate for fungal D-erythroascorbate biosynthesis. Supporting Evidence: PMID:7957197 L-Galactono-1,4-lactone, L-gulono-1,4-lactone and L-xylono-1,4-lactone could also serve as substrates. |
| GO:0050105 L-gulonolactone oxidase activity | IEA GO_REF:0000120 | KEEP AS NON CORE | Summary: The Rhea/EC L-gulonolactone oxidase mapping reflects real alternate substrate use, not the core Candida reaction. Reason: UniProt derives EC 1.1.3.8 from the C. albicans purified-enzyme substrate panel. The activity is retained as non-core because the native fungal pathway oxidizes D-arabinono-1,4-lactone to D-erythroascorbate. Supporting Evidence: file:genes/CANAL/ALO1/ALO1-uniprot.txt EC=1.1.3.8 {ECO:0000269|PubMed:7957197} PMID:7957197 L-Galactono-1,4-lactone, L-gulono-1,4-lactone and L-xylono-1,4-lactone could also serve as substrates. |
| GO:0050660 flavin adenine dinucleotide binding | IEA GO_REF:0000002 | KEEP AS NON CORE | Summary: C. albicans ALO1 is a covalent FAD flavoprotein, but FAD binding is the cofactor component of the oxidase reaction. Reason: The purified enzyme behaved as a flavin-containing enzyme, and sequence analysis identified the conserved FAD-binding region. This is a real molecular property, kept as non-core because the specific oxidase activity is more informative. Supporting Evidence: PMID:7957197 The enzyme showed a typical fluorescence excitation spectrum of a flavin-containing enzyme PMID:11349062 C. albicans ALO also had a putative binding site for covalently bound flavin adenine dinucleotide |
| GO:0070485 dehydro-D-arabinono-1,4-lactone biosynthetic process | IEA GO_REF:0000107 | ACCEPT | Summary: ALO1 catalyzes the terminal step of fungal D-erythroascorbate biosynthesis. Reason: Deleting ALO1 abolished both D-arabinono-1,4-lactone oxidase activity and detectable D-erythroascorbic acid in C. albicans, and overexpressing ALO1 increased both the enzyme activity and intracellular product level. Supporting Evidence: PMID:11349062 In the alo1/alo1 null mutants, the activity of D-arabinono-1,4-lactone oxidase was completely lost and D-erythroascorbic acid could not be detected file:genes/CANAL/ALO1/ALO1-uniprot.txt CC -!- PATHWAY: Cofactor biosynthesis; D-erythroascorbate biosynthesis; |
| GO:0071949 FAD binding | IEA GO_REF:0000002 | KEEP AS NON CORE | Summary: The FAD-binding PCMH-domain mapping is correct for ALO1 but secondary to its D-arabinono-1,4-lactone oxidase activity. Reason: C. albicans ALO is a covalent FAD-containing oxidase with an N-terminal FAD-binding PCMH-type domain. The row is sound, while the core molecular function is the FAD-dependent lactone oxidase reaction. Supporting Evidence: PMID:7957197 The flavin was not released by treatment with SDS file:genes/CANAL/ALO1/ALO1-uniprot.txt FT /note="FAD-binding PCMH-type" |
| GO:1990748 cellular detoxification | IMP PMID:11349062 Deficiency of D-erythroascorbic acid attenuates hyphal growt... | KEEP AS NON CORE | Summary: ALO1 supports oxidative detoxification through its erythroascorbate product, a genuine but broad physiological role. Reason: The cellular detoxification row reasonably summarizes the oxidant hypersensitivity of alo1/alo1 mutants and protection by ALO1 overexpression, but D-erythroascorbate biosynthesis is the direct pathway executed by the enzyme. Supporting Evidence: PMID:11349062 These results indicate that EASC functions as an important antioxidant in C. albicans |
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Download this section (compressed HTML)Q: Does C. albicans ALO1 genuinely localize to the plasma membrane, or was the PMID:19824013 proteomics hit a low-level mitochondrial carryover in the plasma-membrane preparation?
Suggested experts: Candida Genome Database curators
Experiment: Localize epitope-tagged ALO1 in C. albicans with mitochondrial, mitochondrial outer-membrane, and plasma-membrane markers and quantify whether its membrane anchor is required for D-erythroascorbate production.
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