Involvement of alanine racemase in germination of Bacillus cereus spores lacking an intact exosporium

Arch Microbiol. 2014 Feb;196(2):79-85. doi: 10.1007/s00203-013-0946-y. Epub 2013 Dec 18.

Abstract

The L-alanine mediated germination of food isolated Bacillus cereus DSA 1 spores, which lacked an intact exosporium, increased in the presence of D-cycloserine (DCS), which is an alanine racemase (Alr) inhibitor, reflecting the activity of the Alr enzyme, capable of converting L-alanine to the germination inhibitor D-alanine. Proteomic analysis of the alkaline extracts of the spore proteins, which include exosporium and coat proteins, confirmed that Alr was present in the B. cereus DSA 1 spores and matched to that encoded by B. cereus ATCC 14579, whose spore germination was strongly affected by the block of conversion of L- to D-alanine. Unlike ATCC 14579 spores, L-alanine germination of B. cereus DSA 1 spores was not affected by the preincubation with DCS, suggesting a lack of restriction in the reactant accessibility.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alanine / metabolism
  • Alanine / pharmacology
  • Alanine Racemase / chemistry
  • Alanine Racemase / genetics
  • Alanine Racemase / metabolism*
  • Amino Acid Sequence
  • Bacillus cereus / enzymology*
  • Bacillus cereus / genetics
  • Bacillus cereus / metabolism
  • Bacillus cereus / physiology*
  • Cycloserine / metabolism
  • Cycloserine / pharmacology
  • Food Microbiology
  • Molecular Sequence Data
  • Proteomics
  • Spores, Bacterial / cytology
  • Spores, Bacterial / enzymology
  • Spores, Bacterial / physiology

Substances

  • Cycloserine
  • Alanine Racemase
  • Alanine