Cbs
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 (By similarity). 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.
Sequence Similarities
Belongs to the cysteine synthase/cystathionine beta-synthase family.
Cellular localization
- Cytoplasm
- Nucleus
Alternative names
Cystathionine beta-synthase, Beta-thionase, Serine sulfhydrase, Cbs