The vitamin B1 metabolism of Staphylococcus aureus is controlled at enzymatic and transcriptional levels.
Vitamin B1 is in its active form thiamine pyrophosphate (TPP), an essential cofactor for several key enzymes in the carbohydrate metabolism. Mammals must salvage this crucial nutrient from their diet in order to complement the deficiency of de novo synthesis. In the human pathogenic bacterium Staphylococcus aureus, two operons were identified which are involved in vitamin B1 metabolism. The first operon encodes for the thiaminase type II (TenA), 4-amino-5-hydroxymethyl-2-methylpyrimidine kinase (ThiD), 5-(2-hydroxyethyl)-4-methylthiazole kinase (ThiM) and thiamine phosphate synthase (ThiE). The second operon encodes a phosphatase, an epimerase and the thiamine pyrophosphokinase (TPK). The open reading frames of the individual operons were cloned, their corresponding proteins were recombinantly expressed and biochemically analysed. The kinetic properties of the enzymes as well as the binding of TPP to the in vitro transcribed RNA of the proposed operons suggest that the vitamin B1 homeostasis in S. aureus is strongly regulated at transcriptional as well as enzymatic levels.
Müller
Ingrid B
IB
Department of Biochemistry, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
Bergmann
Bärbel
B
Groves
Matthew R
MR
Couto
Isabel
I
Amaral
Leonard
L
Begley
Tadhg P
TP
Walter
Rolf D
RD
Wrenger
Carsten
C
D004262:DNA Restriction Enzymes / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D016680:Genome, Bacterial; D006867:Hydrolases / Q000235:genetics; D007700:Kinetics; D016366:Open Reading Frames; D009876:Operon; D010766:Phosphorylation; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics; D017856:Phosphotransferases (Phosphate Group Acceptor) / Q000235:genetics; D019998:Racemases and Epimerases / Q000235:genetics; D013211:Staphylococcus aureus / Q000378:metabolism*; D013836:Thiamin Pyrophosphokinase / Q000235:genetics; D013831:Thiamine / Q000378:metabolism*; D014158:Transcription, Genetic
D017853:Phosphotransferases (Alcohol Group Acceptor); C051254:hydroxyethylthiazole kinase; C108436:4-amino-5-(hydroxymethyl)-2-methylpyrimidine phosphate kinase; D017856:Phosphotransferases (Phosphate Group Acceptor); D013836:Thiamin Pyrophosphokinase; D006867:Hydrolases; D004262:DNA Restriction Enzymes; C022731:thiaminase II; D019998:Racemases and Epimerases; D013831:Thiamine