Abstract
Thiamine-binding protein of E.coli KG33,auxotrophic for thiamine thiazole was purified to homogeneity by ammonium sulfate treatment, negative DEAE-cellulose chromatography, and affinity chromatography using agarose coupled with thiamine diphosphate. Purified thiamine-binding protein has a molecular weight of 38,000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Although 8M urea reversibly inhibits the binding of thiamine to thiamine-binding protein, no evidence was obtained for subunit formation of the protein in the presence of urea.
