Isolation and Molecular Characterization of Pesticide (Fenitrothion) Resistant Bacteria from Agricultural Field

Abstract

Elimination of pollutants from contaminated sites using microorganisms is a cheaper alternative to chemical technology. There is therefore a need to isolate, identify and characterize the microorganisms that exist and interact in contaminated environment and to isolate the genetic determinants of resistance, frequently located on plasmids and transposons. Investigations were carried out to isolate microbial strains from the fenitrothion polluted soil. Bacteria were isolated using enrichment culture technique containing fenitrothion as sole source of carbon and energy was isolated in pure culture and selected for their ability to degrade fenitrothion. Growth curve experiments showed that the bacterial consortium was able to grow in mineral medium containing fenitrothion as the only carbon source. The microorganisms were identified as Bascillus sp. The identity of the isolate was determined through biochemical and morphological characteristics. For more confirmation, 16s rRNA gene analysis was done using PCR with universal primers. Comparative analysis of the 16s rRNA gene sequences in the Gene Bank database revealed that this bacteria was related to the genus Basicllus substilis. The bacterial strains were found to harbor endogenous plasmids. KEYWORDSBacteria, Biochemical characters, Fenitrothion, Gene sequencing