Open AccessA role for carbon catabolite repression in the metabolism of phosphonoacetate by Agromyces fucosus Vs2
Author(s) -
Naomi O'Loughlin Sheryl,
Graham Robert L.J.,
McMullan Geoff,
Ternan Nigel G.
Publication year - 2006
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2006.00344.x
Subject(s) - catabolite repression , biochemistry , chemistry , metabolism , phosphorus , biology , organic chemistry , mutant , gene
A strain of Agromyces fucosus , designated Vs2, metabolized a range of organophosphonate compounds as sole phosphorus sources for growth and metabolized phosphonoacetate as a sole carbon, energy and phosphorus source for growth. With phosphonoacetate as the sole phosphorus source and a pyruvate carbon source, transient phosphate release to the medium was observed, in contrast to cultures grown with glucose and phosphonoacetate, where no phosphate release to the medium was observed. Carbon catabolite repression, specifically by means of inducer exclusion of phosphonoacetate, was proposed as the mechanism responsible, and phosphonoacetate hydrolase enzyme assays carried out on cell extracts confirmed that induced phosphonoacetate hydrolase activities were indeed higher in cells grown on pyruvate with phosphonoacetate as sole phosphorus source. This phenomenon has not previously been demonstrated in vivo , and must represent a significant metabolic control of organophosphonate metabolism. The catabolite repression phenomenon was also evident when A. fucosus grew on 2‐aminoethylphosphonate as sole phosphorus source, allowing demonstration of a third mode of control for biodegradation of this compound. Excision of stained zymogram gel pieces, followed by tryptic digestion and mass spectrometric analysis, allowed the identification of phosphonoacetate hydrolase‐derived peptides.