Title

Phosphonate metabolism in Helicobacter pylori

Document Type

Article

Publication Date

2010

Abstract

Helicobacter pylori has been shown to degrade two phosphonates, N-phosphonoacetyl-l-aspartate and phosphonoacetate; however, the bacterium does not have any genes homologous to those of the known phosphonate metabolism pathways suggesting that H. pylori may have a novel phosphonate metabolism pathway. Growth of H. pylori on phosphonates was studied and the catabolism of these compounds was measured employing 1H-nuclear magnetic resonance spectroscopy. The specificity of the catabolic enzymes was elucidated by assaying the degradation of several phosphonates and through substrate competition studies. H. pylori was able to utilise phenylphosphonate as a sole source of phosphate for growth. Three strains of H. pylori showed sigmoidal enzyme kinetics of phenylphosphonate catabolism. Allosteric kinetics were removed when lysates were fractionated into cytosolic and membrane fractions. Catabolic rates increased with the addition of DTT, Mg2+ and phosphate and decreased with the addition of EDTA. The physiological properties of H. pylori phosphonate metabolism were characterised and the presence of at least two novel phosphonate catabolism pathways that do not require phosphate starvation growth conditions for activity has been established.

Comments

Due to copyright restrictions the publisher's version/PDF of this article is unavailable for download.

This article may be accessed from the publisher here

Antonie van Leeuwenhoek may be accessed from the National Library of Australia here

The Author:

Professor George L Mendz


Link to Full Text

Share

COinS