A novel polyamine allosteric site of SpeG from Vibrio cholerae is revealed by its dodecameric structure.

ABSTRACT: Spermidine N-acetyltransferase, encoded by the gene speG, catalyzes the initial step in the degradation of polyamines and is a critical enzyme for determining the polyamine concentrations in bacteria. In Escherichia coli, studies have shown that SpeG is the enzyme responsible for acetylating spermidine under stress conditions and for preventing spermidine toxicity. Not all bacteria contain speG, and many bacterial pathogens have developed strategies to either acquire or silence it for pathogenesis. Here, we present thorough kinetic analyses combined with structural characterization of the VCA0947 SpeG enzyme from the important human pathogen Vibrio cholerae. Our studies revealed the unexpected presence of a previously unknown allosteric site and an unusual dodecameric structure for a membe

SUBMITTER: Filippova EV 

PROVIDER: S-EPMC4355314 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature