Abstract
The enzymatic synthesis of thiamine by Staphylococcus aureus FDA 209-P was studied. The active form of pyrimidine moiety was diphosphate of hydroxymethylpyrimidine. Both thiazole moiety and its phosphorylated derivative were active for the synthesis of thiamine by the acetone-dried powder of the microrganism or by the crude enzyme preparation extracted from the powder. Thiazole phosphate was the most active form of thiazole for the enzyme concentrate, purified by the treatment with ammonium sulfate and chromatography on DEAE-cellulose. The activity of free thiazole for the partially purified enzyme was negligible. The reaction products from pyrophosphate of hydroxymethylpyrimidine and thiazole phosphate were examined by paper chromatography and bioautography and proved to be di- and monophosphate of thiamine. The activity of the enzyme was accelerated by the addition of Mn^<2+> or Mg^<2+>. The enzyme was comparatively thermostable.
