Cysteine desulfurase
Template:Short description Template:Infobox enzyme In enzymology, a cysteine desulfurase (Template:EC number) is an enzyme that catalyzes the chemical reaction
- L-cysteine + [enzyme]-cysteine L-alanine + [enzyme]-S-sulfanylcysteine
Thus, the two substrates of this enzyme are L-cysteine and [enzyme]-cysteine], whereas its two products are L-alanine and [enzyme]-S-sulfanylcysteine. One group of authors has given it the acronym hapE, for hydrogen sulfide, alanine, and pyruvate producing enzyme.[1]
This enzyme belongs to the family of transferases, specifically the sulfurtransferases, which transfer sulfur-containing groups. The systematic name of this enzyme class is L-cysteine:[enzyme cysteine] sulfurtransferase. Other names in common use include IscS, NIFS, NifS, SufS, and cysteine desulfurylase.
Function
Bacteria contain cysteine desulfurases to form iron sulfur clusters in proteins.[2] However recently it has been shown that the enzyme, which produces hydrogen sulfide from cysteine, is also a virulence factor, namely for M.pneumoniae, in that it causes both α-hemolysis and β-haemolysis of red blood cells.[1]
In mammals, the enzyme participates in thiamine metabolism.
Structural studies
As of late 2007, only one structure had been solved for this class of enzymes, with the PDB accession code Template:PDB link.
References
Template:Sulfur-containing group transferases Template:Enzymes Template:Portal bar