Identification of the two missing bacterial genes involved in thiamine salvage: thiamine pyrophosphokinase and thiamine kinase

Abstract

The genes encoding thiamine kinase in Escherichia coli (ycfN) and thiamine pyrophosphokinase in Bacillus subtilis (yloS) have been identified. This study completes the identification of the thiamine salvage enzymes in bacteria.

FIG. 1.

Thiamine salvage pathway in E. coli and B. subtilis. The thiamine kinase and thiamine pyrophosphokinase described in this paper are shown in bold. Thiamine kinase is found in E. coli but not in B. subtilis, and thiamine pyrophosphokinase is found in B. subtilis but not in E. coli. HMP, pyrimidine alcohol; Thi-PP, thiamine pyrophosphate; OP, phosphate; OPP, pyrophosphate.

FIG. 2.

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of YcfN and YloS overexpression. Lane 1, total protein from the cell extract of the YcfN overexpression strain before induction; lane 2, total protein from the cell extract of the YcfN overexpression strain after induction; lane 3, soluble protein from the cell extract of the YcfN overexpression strain after induction; lane 4, total protein from the cell extract of the YloS overexpression strain before induction; lane 5, total protein from the cell extract of the YloS overexpression strain after induction; lane 6, soluble protein from the cell extract of the YloS overexpression strain after induction; lane 7, YloS after purification on a HisBind column.