From famine to feast: the role of methylglyoxal production in Escherichia coli

Mol Microbiol. 1998 Feb;27(3):553-62. doi: 10.1046/j.1365-2958.1998.00700.x.


The enzyme methylglyoxal synthase (MGS) was partially purified from Escherichia coli extracts, and the amino-terminal sequence of candidate proteins was determined, based on the native protein being a tetramer of about 69 kDa. Database analysis identified an open reading frame in the E. coli genome, YccG, corresponding to a protein of 16.9 kDa. When amplified and expressed from a controlled promoter, it yielded extracts that contained high levels of MGS activity. MGS expressed from the trc promoter accumulated to approximately 20% of total cell protein, representing approximately 900-fold enhanced expression. This caused no detriment during growth on glucose, and the level of methylglyoxal (MG) in the medium rose to only 0.08 mM. High-level expression of MGS severely compromised growth on xylose, arabinose and glycerol. A mutant lacking MGS was constructed, and it grew normally on a range of carbon sources and on low-phosphate medium. However, the mutant failed to produce MG during growth on xylose in the presence of cAMP, and growth was inhibited.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbon-Oxygen Lyases / genetics*
  • Carbon-Oxygen Lyases / isolation & purification
  • Carbon-Oxygen Lyases / metabolism*
  • Escherichia coli / chemistry
  • Escherichia coli / enzymology*
  • Escherichia coli / genetics*
  • Escherichia coli / growth & development
  • Gene Expression Regulation, Bacterial
  • Genes, Bacterial
  • Glucose / metabolism
  • Glycerol / metabolism
  • Molecular Sequence Data
  • Open Reading Frames
  • Phosphates / metabolism
  • Plasmids / genetics
  • Pyruvaldehyde / metabolism*
  • Xylose / metabolism


  • Phosphates
  • Pyruvaldehyde
  • Xylose
  • Carbon-Oxygen Lyases
  • methylglyoxal synthase
  • Glucose
  • Glycerol

Associated data

  • GENBANK/Y11249