Transfers a sulfur ion to cyanide or to other thiol compounds. Also has weak rhodanese activity (130-fold lower). Its participation in detoxification of cyanide may be small. May be involved in the enhancement of serine sensitivity. •

MSRLLLGLVGALGFSAQAYALEMTPLVDAEWLNEHLDEEELVVLDVRSSIDDGGDAESFA EARIPGSRYSSYTDDGWRETRDSVAGLMPEVSDLEALVGDLGIDNDSAVVIVPAGTGATD FGSAARVYWTLKVLGHDDVAILNGGFAGWEQQGFDVASGEPESYDAAEFDATLREELIAS TEDVEAARESQSQLVDARPADYFAGDNQSPAARVAGTIPGARSLPHQSHLNDQNGAYYLD VEGLQSRINAVELDSSERTIAFCNTGHWAATDWFVLSEVAEFDNIAMYDGSMAAWTISDS RPVQLARDGIKQVKELLN323

	PMID	Title & Author	Abstract	Year
0	21732914	Thioredoxin and dihydrolipoic acid are required for 3-mercaptopyruvate sulfurtransferase to produce hydrogen sulfide. Mikami Y, Shibuya N, Kimura Y, Nagahara N, Ogasawara Y, Kimura H.	H2S (hydrogen sulfide) has recently been recognized as a signalling molecule as well as a cytoprotectant. We recently demonstrated that 3MST (3-mercaptopyruvate sulfurtransferase) produces H2S from 3MP (3-mercaptopyruvate). Although a reducing substance is required for an intermediate persulfide at the active site of 3MST to release H2S, the substance has not been identified. In the present study we show that Trx (thioredoxin) and DHLA (dihydrolipoic acid) associate with 3MST to release H2S. Other reducing substances, such as NADPH, NADH, GSH, cysteine and CoA, did not have any effect on the reaction. We also show that 3MST produces H2S from thiosulfate. The present study provides a new insight into a mechanism for the production of H2S by 3MST.	2011
1	14672665	The "rhodanese" fold and catalytic mechanism of 3-mercaptopyruvate sulfurtransferases: crystal structure of SseA from Escherichia coli. Spallarossa A, Forlani F, Carpen A, Armirotti A, Pagani S, Bolognesi M, Bordo D.	3-Mercaptopyruvate sulfurtransferases (MSTs) catalyze, in vitro, the transfer of a sulfur atom from substrate to cyanide, yielding pyruvate and thiocyanate as products. They display clear structural homology with the protein fold observed in the rhodanese sulfurtransferase family, composed of two structurally related domains. The role of MSTs in vivo, as well as their detailed molecular mechanisms of action have been little investigated. Here, we report the crystal structure of SseA, a MST from Escherichia coli, which is the first MST three-dimensional structure disclosed to date. SseA displays specific structural differences relative to eukaryotic and prokaryotic rhodaneses. In particular, conformational variation of the rhodanese active site loop, hosting the family invariant catalytic Cys residue, may support a new sulfur transfer mechanism involving Cys237 as the nucleophilic species and His66, Arg102 and Asp262 as residues assisting catalysis.	2004
2	12499560	SseA, a 3-mercaptopyruvate sulfurtransferase from Escherichia coli: crystallization and preliminary crystallographic data. Spallarossa A, Carpen A, Forlani F, Pagani S, Bolognesi M, Bordo D.	SseA, the translation product of the Escherichia coli sseA gene, is a 31 kDa protein endowed with 3-mercaptopyruvate:cyanide sulfurtransferase activity in vitro. As such, SseA is the prototype of a sulfurtransferase subfamily distinguished from the better known rhodanese sulfurtransferases, which display thiosulfate:cyanide sulfurtransferase activity. The physiological role of the two homologous enzyme families, whose catalytic activity is centred on a reactive invariant cysteine, is a matter of debate. In this framework, the forthcoming crystal structure analysis of SseA will be based on the tetragonal crystal form (space group P4(1) or P4(3)) reported here, with unit-cell parameters a = b = 150.2, c = 37.9 A.	2003
3	11445076	Properties of the Escherichia coli rhodanese-like protein SseA: contribution of the active-site residue Ser240 to sulfur donor recognition. Colnaghi R, Cassinelli G, Drummond M, Forlani F, Pagani S.	The product of Escherichia coli sseA gene (SseA) was the subject of the present investigation aimed to provide a tool for functional classification of the bacterial proteins of the rhodanese family. E. coli SseA contains the motif CGSGVTA around the catalytic cysteine (Cys238). In eukaryotic sulfurtransferases this motif discriminates for 3-mercaptopyruvate:cyanide sulfurtransferase over thiosulfate:cyanide sulfurtransferases (rhodanese). The biochemical characterization of E. coli SseA allowed the identification of the first prokaryotic protein with a preference for 3-mercaptopyruvate as donor substrate. Replacement of Ser240 with Ala showed that the presence of a hydrophobic residue did not affect the binding of 3-mercaptopyruvate, but strongly prevented thiosulfate binding. On the contrary, substitution of Ser240 with an ionizable residue (Lys) increased the affinity for thiosulfate.	2001

Mikami Y , Shibuya N , Kimura Y , et al. Thioredoxin and dihydrolipoic acid are required for 3-mercaptopyruvate sulfurtransferase to produce hydrogen sulfide[J]. Biochemical Journal, 2011, 439(3):479-485.