Stress-survival responses of a carbon-starved p-nitrophenol-mineralizing Moraxella strain in river water.

Abstract

The effect of carbon starvation on the stress-resistant responses of a p-nitrophenol-mineralizing Moraxella strain was examined in both buffer and river water samples. The Moraxella strain showed optimal stress-resistant responses in a minimal salt buffer when carbon-starved for 1-2 d. In the buffer system, the 1- and 2-day carbon-starved Moraxella cultures survived about 150-, 200-, and 100-fold better than the non-starved cultures when exposed to 43.5 degrees C, 2.7 mol/L NaCl, and 500 micromol/L H2O2 for 4 h, respectively. A green fluorescent protein gene- (gfp) labelled derivative of the Moraxella strain was used to examine the stress-resistant responses of the bacterium in natural river water microcosms. The carbon-starved gfp-labelled Moraxella strain also showed stress-resistant responses against heat, osmotic, and oxidative stresses in the river water samples. Despite the stress-tolerant capability of the carbon-starved gfp-labelled Moraxella cells, they did not exhibit any survival advantage over their non-starved counterparts when inoculated into river water microcosms and incubated at 10 and 22 degrees C for 14 d.

• Authors: Michael Moore, Jack Trevors, Hung Lee, Kam Tin Leung
• Journal: Canadian journal of microbiology (Can J Microbiol) Vol. 51 Issue 3 Pg. 223-9 (Mar 2005) ISSN: 0008-4166 [Print] Canada
• PMID: 15920620 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Buffers
• Culture Media
• Nitrophenols
• Green Fluorescent Proteins
• Carbon

Topics

• Biodegradation, Environmental
• Buffers
• Carbon (metabolism)
• Culture Media
• Gene Expression Regulation, Bacterial
• Green Fluorescent Proteins (genetics, metabolism)
• Heat-Shock Response
• Moraxella (genetics, growth & development, metabolism, physiology)
• Nitrophenols (metabolism)
• Rivers (microbiology)