Molecular and Biochemical Profiling of Pentachlorophenol Utilizing Bacteria from Pulp and Paper Mill Effluent Irrigated Soil in Northern India

Pulp and paper mill is a source of major environmental pollutant’s generating industries which include pentachlorophenol a highly chlorinated aromatic compound. PCP degrading bacterial isolates obtained from pulp and paper mill effluent contaminated site were characterized biochemically and molecularly. Based on their morphological and biochemical characterization, 22 isolates were selected for their ability to grow at different concentrations of PCP. Out of 22 isolates, 8 isolates viz. LK 1, LK 4, LK 39, LK 81, LK 124, LK 141, LK 147 and LK 156 showed significantly higher growth at 100, 300, 500 and 700 ppm of PCP. Growth at 700 ppm reduced significantly due to decrease in pH of the medium to 6.1. These 22 isolates were classified into three major bacterial lineages, a,g-Proteobacteria and Firmicutes. Maximum isolates belonged to Pseudomonas sp such P. aeruginosa, P. citronellolis, P. putida and P. plecoglossicida. PCP degradation by Ensifer adhaerens and Lysinibacillus fusiformis is reported for the first time in present study and these might represent new chlorophenol-degrading taxa. Lysinibacillus fusiformis (LK 156) could show maximum growth at 300 and 500 ppm of PCP.