Analysis of Proteins Expressed by an Abiotic Stress Tolerant Pseudomonas putida (NBAII-RPF9) Isolate Under Saline and High Temperature Conditions

Abstract

Pseudomonas putida (NBAII-RPF9) was identified as an abiotic stress tolerant bacterium capable of growing at 45 °C as well as in 1 M NaCl. The proteins expressed by this bacterium when subjected to these two stresses were analyzed by 2D gel and MALDI-TOF/MS. Two parameters viz., heat/saline shock (20 min at 45 °C/1 M solid NaCl added at mid log phase and incubated for 1 h) and heat/saline tolerance (24 h growth at 45 °C/in 1 M NaCl) were studied. Under heat shock 13 upregulated proteins and 1 downregulated protein were identified and under tolerance 6 upregulated proteins were identified. GroES and GroEL proteins were expressed under both tolerance and shock. Under saline shock 11 upregulated proteins were identified whereas under saline tolerance 6 upregulated proteins were identified and all these proteins had pI between 3 and 10 with molecular weights ranging from 14.3 to 97 kDa. Aspartate carbamoyltransferase was common under both the saline conditions studied. The analysis revealed involvement of heat stress responsive molecular chaperones and membrane proteins during heat stress. During salt stress, proteins involved in metabolic processes were found to be upregulated to favor growth and adaptation of the bacterium. Heat shock chaperones viz., DnaK and DnaJ were expressed under both saline and heat stress. This is the first report of protein profile obtained from a single bacterium under saline and heat stress and the studies reveal the complex mechanisms adapted by the organism to survive under high temperature or saline conditions.

Integrated Physiological, Biochemical, and Molecular Analysis Identifies Important Traits and Mechanisms Associated with Differential Response of Rice Genotypes to Elevated Temperature

“…In rice, reproductive stage is the most sensitive stage to heat (Yoshida et al, 1981 ) and anthesis/flowering is the most severely affected process (Satake and Yoshida, 1978 ; Nakagawa et al, 2002 ; Jagadish et al, 2008 ; Shi et al, 2014 ). In general, high temperature is unfavorable for flowering and grain filling by causing spikelet sterility and shortening the duration of grain-filling phase (Tian et al, 2007 ; Xie et al, 2009 ).…”

“…In general, high temperature is unfavorable for flowering and grain filling by causing spikelet sterility and shortening the duration of grain-filling phase (Tian et al, 2007 ; Xie et al, 2009 ). High temperature during ripening stage generally reduces grain weight and grain-filling phase, and increases the percentage of white chalky rice (Osada et al, 1973 ; Yoshida et al, 1981 ). At elevated temperature, decrease in number of days to 50% flowering and days to grain maturity was observed in all cultivars.…”

Cold Stress and Nitrogen Deficiency Affected Protein Expression of Psychrotrophic Dyadobacter psychrophilus B2 and Pseudomonas jessenii MP1

“…They may help in protein folding and perhaps showed chaperon like activities. Aspartate carbamoyltransferase, NADP-dependent dehydrogenase and Enolase are known to catalyze the pyrimidine biosynthetic pathway, pyruvate metabolism and glycolysis, respectively (Rangeshwaran et al, 2013). These proteins might be crucial for DNA synthesis/repair and energy generation processes.…”

Stress Physiology in Azospirillum and Other PGPRs

“…Heat shock chaperones viz., DnaK and DnaJ were expressed under both saline and heat stress. Also, GroES and GroEL proteins were expressed under both tolerance and shock, indicating the importance of proteins with other molecules in stress tolerance (Rangeshwaran et al 2013 ).…”