Bio Prospecting of Novel Moderate Halophilic Bacterium <i>Marinobacter</i> spp. JS17 Recovered from the West Coast of Karnataka, India

Background: Halophilic bacteria are known for their bioactive molecule production and their unique characteristic features, especially broader salinity, pH and temperature tolerant abilities. Aim: To bioprospect the novel moderate halophilic bacterium Marinobacter spp. JS17 recovered from the west coast of Karnataka, India. Methods: A moderate halophilic bacteria was isolated from the Arabian Sea in Karnataka, India and selected for further studies. As part of the bioprospection, we have carried out the all required morphological, biochemical, enzyme production, and antibiotic resistance potential activities. Molecular identification especially 16S rRNA gene sequencing and phylogenetic studies were done. Results: The strain can able to grow in various concentrations of salts ranging between 0-20% (w/v), the optimum salt required is 10%(w/v), pH ranges from 5-10, and a broad range of temperatures 20-50℃, evident that the halophilic bacterium belonged to an extreme tolerant group. It was discovered that the strain was capable of producing extracellular enzymes like amylase, lipases, esterase, and proteases. Antibiogram investigations have revealed the strain’s ability for multidrug resistance, which establishes the significance of its prospective medical application. Interestingly the strain showed considerable resistance against broad-spectrum antibiotics such as ceftazidime (30mcg/disc), cefotaxime (30mcg/disc), colistin (10mcg/disc) and neomycic. Conclusion: Marinobacter has indicated its multidrug resistance and multi-extracellular enzyme production capabilities. The isolated bacterium was identified as Marinobacter spp. JS17 and the accession of HQ834852were obtained after the gene sequence was deposited in the NCBI platform. 16S rRNA gene sequence examination along with the phenotypic, biochemical, and genotypic data have revealed that the isolated bacterium possesses versatile characteristic features and novel taxon within the Marinobacter genus with only 95% BLAST sequence similarity.