Catalase T, the cytosolic monofunctional heme catalase (EC 1.11.1.6) of Saccharomyces cerevisiae. Ctt1 is a homotetramer that dismutates hydrogen peroxide to water and oxygen in the cytosol. Unlike its paralog Cta1 (peroxisomal catalase A) it lacks a peroxisomal targeting signal. CTT1 expression is stress-inducible, and cytosolic catalase activity is induced by reactive nitrogen species in flavohemoglobin- or GSNOR-deficient cells and can degrade peroxynitrite in vitro. Loss of both catalases increases oxidative protein damage.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0000302 response to reactive oxygen species | IMP PMID:15893481 Catalases protect cellular proteins from oxidative modificat... | KEEP AS NON CORE | Summary: Lushchak & Gospodaryov 2005: combined loss of cytosolic (Ctt1) and peroxisomal (Cta1) catalases increased protein carbonylation on ethanol, showing catalases protect against ROS damage. Reason: Physiological consequence of H2O2 removal; non-core relative to H2O2 catabolism. Supporting Evidence: PMID:15893481 Growing in ethanol the strain deficient in cytosolic and peroxisomal catalases had 7.1-fold higher level of carbonyl proteins than that of wild-type strain. |
| GO:0004096 catalase activity | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT IBA for catalase activity from the monofunctional heme catalase clade; Ctt1 is a clade member with the catalase signature. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SIMILARITY: Belongs to the catalase family. file:yeast/CTT1/CTT1-uniprot.txt serves to protect cells from the toxic effects of hydrogen peroxide. |
| GO:0004096 catalase activity | IDA PMID:19463791 A novel role of catalase in detoxification of peroxynitrite ... | ACCEPT | Summary: Sahoo et al. 2009 measured cytosolic catalase (Ctt1) activity in yeast and its induction in yhb1 and sfa1 mutants, and showed in vitro that catalase degrades peroxynitrite. Supports catalase activity of the cytosolic enzyme. Supporting Evidence: PMID:19463791 induction of cytosolic catalase was found at activity as well as gene expression level in mutants but not in wild type. PMID:19463791 Our in vitro studies confirmed the role of catalase in protection against peroxynitrite-mediated oxidation and nitration and also in peroxynitrite catabolism. |
| GO:0004096 catalase activity | IEA GO_REF:0000120 | ACCEPT | Summary: InterPro/RHEA catalase mapping; correct. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SIMILARITY: Belongs to the catalase family. |
| GO:0004096 catalase activity | RCA GO_REF:0000123 | ACCEPT | Summary: YeastPathways superoxide radicals degradation (DETOX1-PWY) assigns Ctt1 the catalase step (2 H2O2 -> 2 H2O + O2); correct reaction. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt serves to protect cells from the toxic effects of hydrogen peroxide. |
| GO:0005737 cytoplasm | HDA PMID:14562095 Global analysis of protein localization in budding yeast. | ACCEPT | Summary: Huh et al. 2003 GFP survey localised Ctt1-GFP to the cytoplasm; UniProt cites this for the cytoplasmic location. Supporting Evidence: PMID:14562095 We classify these proteins, representing 75% of the yeast proteome, into 22 distinct subcellular localization categories file:yeast/CTT1/CTT1-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm |
| GO:0005737 cytoplasm | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT IBA for cytoplasm across catalases; correct for Ctt1, the cytosolic yeast catalase. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm |
| GO:0005737 cytoplasm | IEA GO_REF:0000044 | ACCEPT | Summary: UniProt subcellular-location mapping (SL-0086 Cytoplasm); correct. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm |
| GO:0005739 mitochondrion | IBA GO_REF:0000033 | REMOVE | Summary: PAINT IBA for mitochondrion at node PTN000157252, whose only with/from source is the paralog CTA1. Mitochondrial import was shown specifically for catalase A (Cta1); there is no evidence for mitochondrial Ctt1, which is the cytosolic form. Reason: Paralog-specific location (Cta1) propagated to the cytosolic paralog Ctt1; no Ctt1-specific evidence. Propagation Review Root cause: PROPAGATION BAD Failure modes: WRONG ORTHOLOG OR PARALOG COMPARTMENT OR COMPLEX MISMATCH Sources checked: PANTHER:PTN000157252 · PTN000157252 SUPPORTS SOURCE BUT NOT TARGET The mitochondrion location at this node is grounded by CTA1 (SGD:S000002664) and animal peroxisomal catalases; the yeast paralog Ctt1 has no PTS1 (C-terminus ...SIASAN) and is the cytosolic catalase. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm file:yeast/CTT1/CTT1-uniprot.txt is catalase A, which is the peroxisomal form. |
| GO:0005777 peroxisome | IBA GO_REF:0000033 | REMOVE | Summary: PAINT IBA for peroxisome from animal catalases and yeast CTA1. Ctt1 lacks a PTS1 and is designated the cytoplasmic catalase, in contrast to peroxisomal catalase A; no evidence places Ctt1 in peroxisomes. Reason: Peroxisomal location belongs to the paralog Cta1; Ctt1 is cytosolic. Propagation Review Root cause: PROPAGATION BAD Failure modes: WRONG ORTHOLOG OR PARALOG COMPARTMENT OR COMPLEX MISMATCH Sources checked: PANTHER:PTN000157252 · PTN000157252 SUPPORTS SOURCE BUT NOT TARGET The peroxisome location at this node is grounded by CTA1 (SGD:S000002664) and animal peroxisomal catalases; the yeast paralog Ctt1 has no PTS1 (C-terminus ...SIASAN) and is the cytosolic catalase. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm file:yeast/CTT1/CTT1-uniprot.txt is catalase A, which is the peroxisomal form. |
| GO:0005829 cytosol | RCA GO_REF:0000123 | ACCEPT | Summary: YeastPathways DETOX1-PWY places the catalase reaction in the cytosol; correct for Ctt1. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SUBCELLULAR LOCATION: Cytoplasm PMID:19463791 induction of cytosolic catalase was found at activity as well as gene expression level in mutants but not in wild type. |
| GO:0006979 response to oxidative stress | IEA GO_REF:0000002 | TOO GENERAL | Summary: InterPro catalase signature mapping to response to oxidative stress; broad response term. Reason: Broad response term; core process is H2O2 catabolism. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt serves to protect cells from the toxic effects of hydrogen peroxide. |
| GO:0019430 removal of superoxide radicals | RCA GO_REF:0000123 | REMOVE | Summary: Inherited from the YeastPathways superoxide radicals degradation pathway (DETOX1-PWY). Ctt1 degrades H2O2, not superoxide. Reason: GO:0019430 removal of superoxide radicals describes conversion of superoxide (O2-), e.g. by superoxide dismutase. Catalase acts on hydrogen peroxide, the product of SOD, and does not react with superoxide. The row is inherited from the YeastPathways "superoxide radicals degradation" pathway (DETOX1-PWY), whose name covers both the SOD and catalase steps; the catalase step is captured by GO:0042744 hydrogen peroxide catabolic process. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt serves to protect cells from the toxic effects of hydrogen peroxide. |
| GO:0020037 heme binding | IBA GO_REF:0000033 | KEEP AS NON CORE | Summary: PAINT IBA for heme binding (from human CAT); Ctt1 is a heme catalase. Cofactor binding. Reason: Cofactor binding underlying catalase activity. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SIMILARITY: Belongs to the catalase family. |
| GO:0020037 heme binding | IEA GO_REF:0000002 | KEEP AS NON CORE | Summary: InterPro catalase heme-binding domain mapping; correct cofactor binding. Reason: Cofactor binding underlying catalase activity. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt SIMILARITY: Belongs to the catalase family. |
| GO:0042542 response to hydrogen peroxide | IBA GO_REF:0000033 | KEEP AS NON CORE | Summary: PAINT IBA for response to hydrogen peroxide; correct framing of catalase function at the response level. Reason: Response-level term; H2O2 catabolic process is the direct process. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt serves to protect cells from the toxic effects of hydrogen peroxide. |
| GO:0042744 hydrogen peroxide catabolic process | IBA GO_REF:0000033 | ACCEPT | Summary: PAINT IBA for hydrogen peroxide catabolic process; the direct process carried out by catalase T. Supporting Evidence: file:yeast/CTT1/CTT1-uniprot.txt serves to protect cells from the toxic effects of hydrogen peroxide. file:yeast/CTT1/CTT1-uniprot.txt SIMILARITY: Belongs to the catalase family. |
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Cytosolic catalase T; has a role in protection from oxidative damage by hydrogen peroxide
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