MetaCyc Protein Class: a carboxy-adenylated-[ThiS sulfur-carrier protein]

Synonyms: adenylyl-[ThiS], an adenylated ThiS sulfur-carrier protein, a carboxy-adenylated ThiS sulfur-carrier protein

Superclasses: a polypeptidea ThiS sulfur-carrier protein
a proteina modified protein

ThiS is the sulfur source for the thiazole moiety in thiamin biosynthesis. In a reaction catalyzed by the ThiF protein, the carboxy-terminal glycine of ThiS is adenylated. Sulfur is then transferred from an S-sulfanyl-[ThiI sulfur-carrier protein], forming a thiocarboxy-adenylate, in a reaction catalyzed by ThiF and the ThiI protein [Begley99, Taylor98a]. The thiocarboxy-adenylate form of ThiS is one of the substrates used by thiazole synthase.

a carboxy-adenylated-[ThiS sulfur-carrier protein] compound structure

ThiS-COAMP (Escherichia coli K-12 substr. MG1655)

SMILES: C(C3(C(C(C(N2(C1(=C(C(=NC=N1)N)N=C2)))O3)O)O))OP(OC(CNC(CN[a ThiS sulfur-carrier protein])=O)=O)([O-])=O

Reactions known to consume the compound:

thiazole biosynthesis I (facultative anaerobic bacteria) :
a ThiS sulfur-carrier protein + ATP + H+a carboxy-adenylated-[ThiS sulfur-carrier protein] + diphosphate
an S-sulfanyl-[ThiI sulfur-carrier protein] + a carboxy-adenylated-[ThiS sulfur-carrier protein] + 2 a reduced ferredoxin [iron-sulfur] cluster → a thiocarboxy-[ThiS-Protein] + a ThiI sulfur-carrier protein + AMP + 2 an oxidized ferredoxin [iron-sulfur] cluster

thiazole biosynthesis II (aerobic bacteria) :
a ThiS sulfur-carrier protein + ATP + H+a carboxy-adenylated-[ThiS sulfur-carrier protein] + diphosphate
an [L-cysteine desulfurase] L-cysteine persulfide + a carboxy-adenylated-[ThiS sulfur-carrier protein] + an reduced unknown electron acceptor → a thiocarboxy-[ThiS-Protein] + an [L-cysteine desulfurase]-L-cysteine + AMP + an oxidized unknown electron acceptor + 2 H+

Reactions known to produce the compound:

thiazole biosynthesis I (facultative anaerobic bacteria) , thiazole biosynthesis II (aerobic bacteria) :
1-deoxy-D-xylulose 5-phosphate + 2-iminoacetate + a thiocarboxy-[ThiS-Protein] → 2-[(2R,5Z)-2-carboxy-4-methylthiazol-5(2H)-ylidene]ethyl phosphate + a ThiS sulfur-carrier protein + 2 H2O

Gene-Reaction Schematic

Gene-Reaction Schematic


Begley99: Begley TP, Downs DM, Ealick SE, McLafferty FW, Van Loon AP, Taylor S, Campobasso N, Chiu HJ, Kinsland C, Reddick JJ, Xi J (1999). "Thiamin biosynthesis in prokaryotes." Arch Microbiol 1999;171(5);293-300. PMID: 10382260

Taylor98a: Taylor SV, Kelleher NL, Kinsland C, Chiu HJ, Costello CA, Backstrom AD, McLafferty FW, Begley TP (1998). "Thiamin biosynthesis in Escherichia coli. Identification of this thiocarboxylate as the immediate sulfur donor in the thiazole formation." J Biol Chem 273(26);16555-60. PMID: 9632726

Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by Pathway Tools version 19.5 (software by SRI International) on Wed Nov 25, 2015, biocyc11.