Conserving a volatile metabolite: A role for carboxysome-like organelles in Salmonella enterica

Joseph T. Penrod, John R. Roth

Research output: Contribution to journalArticle

120 Scopus citations


Salmonellae can use ethanolamine (EA) as a sole source of carbon and nitrogen. This ability is encoded by an operon (eut) containing 17 genes, only 6 of which are required under standard conditions (37°C; pH 7.0). Five of the extra genes (eutM, -N, -L, -K, and -G) become necessary under conditions that favor loss of the volatile intermediate, acetaldehyde, which escapes as a gas during growth on EA and is lost at a higher rate from these mutants. The eutM, -N, -L, and -K genes encode homologues of shell proteins of the carboxysome, an organelle shown (in other organisms) to concentrate CO2. We propose that carboxysome-like organelles help bacteria conserve certain volatile metabolites-CO2 or acetaldehyde-perhaps by providing a low-pH compartment. The EutG enzyme converts acetaldehyde to ethanol, which may improve carbon retention by forming acetals; alternatively, EutG may recycle NADH within the carboxysome.

Original languageEnglish (US)
Pages (from-to)2865-2874
Number of pages10
JournalJournal of Bacteriology
Issue number8
StatePublished - Apr 2006


ASJC Scopus subject areas

  • Applied Microbiology and Biotechnology
  • Immunology

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