ThiC is an [Fe-S] cluster protein that requires AdoMet to generate the 4-amino-5-hydroxymethyl-2-methylpyrimidine moiety in thiamin synthesis.
Thiamin pyrophosphate is a required cofactor in all organisms. The biosynthesis of thiamin requires the independently synthesized 4-amino-5-hydroxymethyl-2-methylpyrimidine pyrophosphate (HMP-PP) and 5-hydroxyethyl-4-methylthiazole phosphate (THZ-P) moieties. In bacteria, the pyrimidine moiety is derived from 5-aminoimidazole ribotide (AIR), and ThiC is the only gene product known to be required for this conversion in vivo. We report here the purification and characterization of the ThiC protein from Salmonella enterica. The data showed this protein generated HMP when AIR, S-adenosylmethionine (AdoMet), and an appropriate reducing agent were present. It is further shown that ThiC carries an oxygen labile [Fe-S] cluster essential for this activity.
Martinez-Gomez
N Cecilia
NC
Department of Bacteriology, University of Wisconsin, 1550 Linden Drive, Madison, Wisconsin 53706, USA.
Downs
Diana M
DM
D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D011756:Diphosphates / Q000378:metabolism; D007506:Iron-Sulfur Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D010084:Oxidation-Reduction; D011743:Pyrimidines / Q000378:metabolism*; D012265:Ribonucleotides / Q000378:metabolism; D012436:S-Adenosylmethionine / Q000378:metabolism*; D019779:Salmonella enterica / Q000378:metabolism; D013831:Thiamine / Q000096:biosynthesis*
C101901:4-amino-5-hydroxymethyl-2-methylpyrimidine; C532145:4-amino-5-hydroxymethyl-2-methylpyrimidine pyrophosphate; D001426:Bacterial Proteins; D011756:Diphosphates; D007506:Iron-Sulfur Proteins; D011743:Pyrimidines; D012265:Ribonucleotides; C105797:ThiC protein, Bacteria; C024828:aminoimidazole ribotide; D012436:S-Adenosylmethionine; D013831:Thiamine