Understanding the molecular basis of plant growth promotional effect of Pseudomonas fluorescens on rice through protein profiling

<p>Abstract</p> <p>Background</p> <p>Plant Growth Promoting Rhizobacteria (PGPR), <it>Pseudomonas fluorescens </it>strain KH-1 was found to exhibit plant growth promotional activity in rice under both <it>in-vitro </it>and <it>in-vivo </it>conditions. But the mechanism underlying such promotional activity of <it>P. fluorescens </it>is not yet understood clearly. In this study, efforts were made to elucidate the molecular responses of rice plants to <it>P. fluorescens </it>treatment through protein profiling. Two-dimensional polyacrylamide gel electrophoresis strategy was adopted to identify the PGPR responsive proteins and the differentially expressed proteins were analyzed by mass spectrometry.</p> <p>Results</p> <p>Priming of <it>P. fluorescens</it>, 23 different proteins found to be differentially expressed in rice leaf sheaths and MS analysis revealed the differential expression of some important proteins namely putative p23 co-chaperone, Thioredoxin h- rice, Ribulose-bisphosphate carboxylase large chain precursor, Nucleotide diPhosphate kinase, Proteosome sub unit protein and putative glutathione S-transferase protein.</p> <p>Conclusion</p> <p>Functional analyses of the differential proteins were reported to be directly or indirectly involved in growth promotion in plants. Thus, this study confirms the primary role of PGPR strain KH-1 in rice plant growth promotion.</p

Complete Genome Sequence Analysis of <i>Bacillus subtilis</i> Bbv57, a Promising Biocontrol Agent against Phytopathogens

Plant growth-promoting rhizobacteria (PGPR) are a group of root-associated beneficial bacteria emerging as one of the powerful agents in sustainable plant disease management. Among the PGPR, Bacillus sp. has become a popular biocontrol agent for controlling pests and the diseases of several crops of agricultural and horticultural importance. Understanding the molecular basis of the plant growth-promoting and biocontrol abilities of Bacillus spp. will allow us to develop multifunctional microbial consortia for sustainable agriculture. In our study, we attempted to unravel the genome complexity of the potential biocontrol agent Bacillus subtilis Bbv57 (isolated from the betelvine’s rhizosphere), available at TNAU, Coimbatore. A WGS analysis generated 26 million reads, and a de novo assembly resulted in the generation of 4,302,465 bp genome of Bacillus subtilis Bbv57 containing 4363 coding sequences (CDS), of which 4281 were functionally annotated. An analysis of 16S rRNA revealed its 100% identity to Bacillus subtilis IAM 12118. A detailed data analysis identified the presence of >100 CAZymes and nine gene clusters involved in the production of secondary metabolites that exhibited antimicrobial properties. Further, Bbv57 was found to harbor 282 unique genes in comparison with 19 other Bacillus strains, requiring further exploration