Names & Taxonomy
- Uniprot ID:
- P35520
- Entry Name:
- CBS_HUMAN
- Status:
- reviewed
- Protein Names:
- Cystathionine beta-synthase (EC 4.2.1.22) (Beta-thionase) (Serine sulfhydrase)
- Gene Names:
- CBS
- Gene Names Primary:
- CBS
- Organism:
- Homo sapiens (Human)
Structure
- Length:
- 551
- Sequence:
- MPSETPQAEVGPTGCPHRSGPHSAKGSLEKGSPEDKEAKEPLWIRPDAPSRCTWQLGRPASESPHHHTAPAKSPKILPDILKKIGDTPMVRINKIGKKFGLKCELLAKCEFFNAGGSVKDRISLRMIEDAERDGTLKPGDTIIEPTSGNTGIGLALAAAVRGYRCIIVMPEKMSSEKVDVLRALGAEIVRTPTNARFDSPESHVGVAWRLKNEIPNSHILDQYRNASNPLAHYDTTADEILQQCDGKLDMLVASVGTGGTITGIARKLKEKCPGCRIIGVDPEGSILAEPEELNQTEQTTYEVEGIGYDFIPTVLDRTVVDKWFKSNDEEAFTFARMLIAQEGLLCGGSAGSTVAVAVKAAQELQEGQRCVVILPDSVRNYMTKFLSDRWMLQKGFLKEEDLTEKKPWWWHLRVQELGLSAPLTVLPTITCGHTIEILREKGFDQAPVVDEAGVILGMVTLGNMLSSLLAGKVQPSDQVGKVIYKQFKQIRLTDTLGRLSHILEMDHFALVVHEQIQYHSTGKSSQRQMVFGVVTAIDLLNFVAAQERDQK
- Proteomes:
- UP000005640
Subcellular location
- Subcellular Location:
- Cytoplasm
Function
- Function:
- Hydro-lyase catalyzing the first step of the transsulfuration pathway, where the hydroxyl group of L-serine is displaced by L-homocysteine in a beta-replacement reaction to form L-cystathionine, the precursor of L-cysteine. This catabolic route allows the elimination of L-methionine and the toxic metabolite L-homocysteine (PubMed:23981774, PubMed:20506325, PubMed:23974653). Also involved in the production of hydrogen sulfide, a gasotransmitter with signaling and cytoprotective effects on neurons (By similarity).
- Pathway:
- Amino-acid biosynthesis; L-cysteine biosynthesis; L-cysteine from L-homocysteine and L-serine: step 1/2.
- Catalytic Activity:
- L-serine + L-homocysteine = L-cystathionine + H(2)O.
- Cofactor:
- COFACTOR: Name=pyridoxal 5'-phosphate; Xref=ChEBI:CHEBI:597326;
- Enzyme Regulation:
- ENZYME REGULATION: Allosterically activated by S-adenosyl-methionine/AdoMet. Activated by S-adenosylhomocysteine/AdoHcy (PubMed:20506325). Binds non-covalently to a heme group that may control the redox sensitivity of the enzyme (PubMed:11483494, PubMed:12173932, PubMed:22738154).
- Cross Reference Drug Bank:
- DB00151 DB00133 DB00118
- Gene Ontology Go:
- cytoplasm
cytosol
nucleus
carbon monoxide binding
cystathionine beta-synthase activity
cysteine synthase activity
enzyme binding
heme binding
identical protein binding
metal ion binding
modified amino acid binding
nitric oxide binding
nitrite reductase (NO-forming) activity
oxygen binding
protein homodimerization activity
pyridoxal phosphate binding
S-adenosyl-L-methionine binding
ubiquitin protein ligase binding
cellular nitrogen compound metabolic process
cysteine biosynthetic process
cysteine biosynthetic process from serine
cysteine biosynthetic process via cystathionine
DNA protection
homocysteine catabolic process
homocysteine metabolic process
hydrogen sulfide biosynthetic process
L-cysteine catabolic process
L-serine catabolic process
L-serine metabolic process
oxidation-reduction process
selenium compound metabolic process
small molecule metabolic process
sulfur amino acid metabolic process
transsulfuration - Gene Ontology Biological Process:
- cellular nitrogen compound metabolic process
cysteine biosynthetic process
cysteine biosynthetic process from serine
cysteine biosynthetic process via cystathionine
DNA protection
homocysteine catabolic process
homocysteine metabolic process
hydrogen sulfide biosynthetic process
L-cysteine catabolic process
L-serine catabolic process
L-serine metabolic process
oxidation-reduction process
selenium compound metabolic process
small molecule metabolic process
sulfur amino acid metabolic process
transsulfuration - Gene Ontology Molecular Function:
- carbon monoxide binding
cystathionine beta-synthase activity
cysteine synthase activity
enzyme binding
heme binding
identical protein binding
metal ion binding
modified amino acid binding
nitric oxide binding
nitrite reductase (NO-forming) activity
oxygen binding
protein homodimerization activity
pyridoxal phosphate binding
S-adenosyl-L-methionine binding
ubiquitin protein ligase binding - Gene Ontology Cellular Component:
- cytoplasm
cytosol
nucleus - Keywords:
- 3D-structure
Allosteric enzyme
Alternative splicing
Amino-acid biosynthesis
CBS domain
Complete proteome
Cysteine biosynthesis
Cytoplasm
Disease mutation
Heme
Iron
Isopeptide bond
Lyase
Metal-binding
Nucleus
Phosphoprotein
Polymorphism
Pyridoxal phosphate
Reference proteome
Ubl conjugation - Interacts With:
- Itself; Q08426; Q13526; P54619; P25786; P57075; Q7KZS0
Publication
- PubMed ID:
- 7903580 7598711 8022826 9383285 9790750 14702039 10830953 15489334 681363 17087506 19413330 21269460 21406692 24275569 20506325 11483494 12173932 10338090 1301198 8353501 7506602 7981678 7849717 7967489 7611293 7762555 7635485 8528202 7564249 8755636 8803779 9156316 9361025 8990018 9266356 10462600 10215408 9889017 10408774 11013450 11359213 11553052 12007221 12124992 12815602 14635102 15146473 15365998 15993874 16205833 16429402 21520339 21240075 22738154 23981774 25044645 23974653