Mutational, proteomic and metabolomic analysis of a plant growth promoting copper-resistant Pseudomonas spp.
Article first published online: 21 AUG 2012
© 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved
FEMS Microbiology Letters
Volume 335, Issue 2, pages 140–148, October 2012
How to Cite
Li, K., Pidatala, R. R. and Ramakrishna, W. (2012), Mutational, proteomic and metabolomic analysis of a plant growth promoting copper-resistant Pseudomonas spp. FEMS Microbiology Letters, 335: 140–148. doi: 10.1111/j.1574-6968.2012.02646.x
- Issue published online: 24 SEP 2012
- Article first published online: 21 AUG 2012
- Accepted manuscript online: 30 JUL 2012 05:09AM EST
- Manuscript Accepted: 25 JUL 2012
- Manuscript Revised: 14 JUN 2012
- Manuscript Received: 16 JAN 2012
- transposon insertion;
- Clp protease
Pseudomonas sp. TLC6-6.5-4 is a multiple metal resistant plant growth-promoting bacteria isolated from copper-contaminated lake sediments. In this study, a comprehensive analysis of genes involved in copper resistance was performed by generating a library of transposon (Tn5) mutants. Two copper-sensitive mutants with significant reduction in copper resistance were identified: CSM1, a mutant disrupted in trpA gene (tryptophan synthase alpha subunit), and CSM2, a mutant disrupted in clpA gene (ATP-dependent Clp protease). Proteomic and metabolomic analyses were performed to identify biochemical and molecular mechanisms involved in copper resistance using CSM2 due to its lower minimum inhibitory concentration compared with CSM1 and the wild type. Proteomic analysis revealed that disruption of Clp protease gene up-regulated molecular chaperones and down-regulated the expression of enzymes related to tRNA modification, whereas metabolomic analysis showed that amino acid and oligosaccharide transporters that are part of ATP-binding cassette (ABC) transporters pathways were down-regulated. Further, copper stress altered metabolic pathways including the tricarboxylic acid cycle, protein absorption and glyoxylate metabolism.