Isolation and biological characterization of highly potent Tributyltin chloride resistant bacteria Alcaligenes sp. swo (Strain Sd) from marine water of Goa, India

Water samples were collected from various sampling sites surrounding the ship building industries in Goa and plated on Zobell marine agar (ZMA), Nutrient agar (NA) and Mineral salt medium agar (MSMA) containing 0.1 mM tributyltin chloride (TBTC). The physicochemical characteristics of the water samples were determined. The total viable counts of bacteria ranged from 58 x 10² cfu/ml in MSMA+TBTC to 40.6 x 10⁶ cfu/ml in ZMA+TBTC. This clearly indicates predominance of TBTC tolerant and degrading bacterial isolates in marine water of Goa. Although, several highly TBTC tolerant bacterial isolates were screened, one bacterial strain tolerated up to 7 mM TBTC and showed prominent growth in MSM supplemented upto 5mM TBTC. This clearly indicates that TBTC resistant bacterial isolate utilizes TBTC as a sole carbon source. Based on morphological, biochemical, and molecular characteristics (l6S rDNA Sequence & taxonomic phenogram) this TBTC resistant isolate have been grouped in Alcaligenes sp. swo.