Decolorization of p-nitrophenol and draft genome sequence of Pseudomonas sp. strain PNPG3: A preliminary report

Abstract

Aim: To study decolorization (with concomitant depletion) of p-nitrophenol by a bacterial strain designated as PNPG3 and determination of draft genome sequence of the strain to understand its potential. Methodology: A comparative study of PNP’s decolorization (with concomitant removal) in three different test conditions was undertaken. The experiment was carried out in one-liter volume Schott Duran bottles. Genomic DNA was extracted and draft genome sequence was determined using Illumina HiSeqX platform. Raw reads were assembled and subjected to subsystem classification using several bioinformatics tools (RAST, PATRIC, and NCBI’s PGAP pipelines). The genome sequence was deposited at the NCBI Genome database and the strain PNPG3 was also deposited at MTCC, IMTECH, Chandigarh. Results: The bacterial strain PNPG3 could carry out decolorization with concomitant removal of PNP in all three sets of experiments, including one set, where only distilled water was used. The best decolorization (with concomitant PNP removal) capacity was recorded for set D (with Minimal Medium, MM; PNP, and free cells) followed by set E (MM, PNP, and immobilized cells) and set B (distilled water, PNP and free cells) conditions. The size of the draft genome sequence of the strain PNPG3 was 6,566,321 bp, with 62.26% GC contents. The genome had 6210 protein-coding sequences and 66 tRNA genes. The predictive presence of different types of proteases and siderophore receptors indicated its possible potential for industrial applications and plant growth-promoting activities. Interpretation: The bacterium Pseudomonas sp. strain PNPG3 has the capacity to decolorize p-nitrophenol even in presence of distilled water and it remains viable for up to twelve days. The genome sequence revealed that the strain harbored genes responsible for the metabolism of aromatic compounds, chemotaxis, protease, and siderophore receptors indicating the versatile nature of the strain. Key words: Decolorization, P-nitrophenol, Pseudomonas sp., RAST, Xenobiotic