Whole Genome Sequencing and Tn-Insertion Mutagenesis of CMS to Probe Its Antagonistic Activity Against Rice Bacterial Blight Disease.

The Gram-negative bacterium is a novel bacterium that uses shrimp shell waste as its sole sources of carbon and nitrogen. It is a versatile bacterium with potential for use in biological control, with activities including toxicity toward insects, fungi, and the rice pathogen pv (). In this study, the complete 5.08-Mb genome sequence of CMS was determined by a combination of NGS/Sanger sequencing and optical mapping. Comparison of optical maps of seven species showed that is most closely related to KT 2400. We screened a total of 11,646 individual Tn-transponson tagged strains to identify genes that are involved in the production and regulation of the iron-chelator pyoverdine in , which is a key anti- factor. Our results indicated that the two-component system (TCS) EnvZ/OmpR plays a positive regulatory role in the production of pyoverdine, whereas the sigma factor RpoS functions as a repressor. The knowledge of the molecular basis of the regulation of pyoverdine by provided herein will be useful for its development for use in biological control, including as an anti- agent.