cystathionine beta-synthase
Last updated 21 Jun 2022
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The CBS gene provides instructions for making an enzyme called cystathionine beta-synthase. This enzyme acts in a chemical pathway and is responsible for using vitamin B6 to convert building block of proteins (amino acid) called homocysteine and serine to a molecule called cytathionine. Another enzyme then converts cystathionine to the amino acid cysteine, which is used to build proteins or is broken down and excreted in urine. Additionally, other amino acids, including methionine, are produced in this pathway.
Normal function
The CBS gene provides instructions for making an enzyme called cystathionine beta-synthase. This enzyme acts in a chemical pathway and is responsible for using vitamin B6 to convert building block of proteins (amino acid) called homocysteine and serine to a molecule called cytathionine. Another enzyme then converts cystathionine to the amino acid cysteine, which is used to build proteins or is broken down and excreted in urine. Additionally, other amino acids, including methionine, are produced in this pathway.
Conditions referring to this gene or chromosome
Other names
beta-thionase
CBS_HUMAN
HIP4
methylcysteine synthase
serine sulfhydrase
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Further reading and references
- cystathionine beta-synthase; MedlinePlus, National Library of Medicine.
- Banerjee R, Zou CG. Redox regulation and reaction mechanism of human cystathionine-beta-synthase: a PLP-dependent hemesensor protein. Arch Biochem Biophys. 2005 Jan 1;433(1):144-56. doi: 10.1016/j.abb.2004.08.037.
- Kozich V, Sokolova J, Klatovska V, Krijt J, Janosik M, Jelinek K, Kraus JP. Cystathionine beta-synthase mutations: effect of mutation topology on folding and activity. Hum Mutat. 2010 Jul;31(7):809-19. doi: 10.1002/humu.21273.
- Kraus JP, Janosik M, Kozich V, Mandell R, Shih V, Sperandeo MP, Sebastio G, de Franchis R, Andria G, Kluijtmans LA, Blom H, Boers GH, Gordon RB, Kamoun P, Tsai MY, Kruger WD, Koch HG, Ohura T, Gaustadnes M. Cystathionine beta-synthase mutations in homocystinuria. Hum Mutat. 1999;13(5):362-75. doi: 10.1002/(SICI)1098-1004(1999)13:53.0.CO;2-K.
- Meier M, Oliveriusova J, Kraus JP, Burkhard P. Structural insights into mutations of cystathionine beta-synthase. Biochim Biophys Acta. 2003 Apr 11;1647(1-2):206-13. doi: 10.1016/s1570-9639(03)00048-7.
- Miles EW, Kraus JP. Cystathionine beta-synthase: structure, function, regulation, and location of homocystinuria-causing mutations. J Biol Chem. 2004 Jul 16;279(29):29871-4. doi: 10.1074/jbc.R400005200. Epub 2004 Apr 15. No abstract available.
- Moat SJ, Bao L, Fowler B, Bonham JR, Walter JH, Kraus JP. The molecular basis of cystathionine beta-synthase (CBS) deficiency in UK and US patients with homocystinuria. Hum Mutat. 2004 Feb;23(2):206. doi: 10.1002/humu.9214.
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