TITLE:
Genome Shuffling of Pseudomonas Sp. Ioca11 for Improving Degradation of Polycyclic Aromatic Hydrocarbons
AUTHORS:
Manoj Kumar, Mahendra Pratap Singh, Deepak Kumar Tuli
KEYWORDS:
PAHs; Biodegradation; Genome Shuffling; Mutagenesis
JOURNAL NAME:
Advances in Microbiology,
Vol.2 No.1,
March
27,
2012
ABSTRACT: A Pseudomonas sp. strain IOCa11 exhibiting broad substrate profile for polycyclic aromatic hydrocarbons (PAHs) degradation was isolated by enrichment techniques from oil-contaminated soil. We applied genome shuffling of Pseudomonas sp. strain IOCa11 to achieve improved degradation of PAHs. The initial mutant population was generated by nitrosoguanidine treatment and population exhibiting improved phenotype was subjected to multiple round of protoplast fusion in order to allow recombination between genomes. Mutant, designated as SF-IOC11-16A, obtained after recursive protoplast fusion showed substantial improvement in ability to degrade PAHs in liquid media. It could degrade 98% DBT in 72 hours in comparison to 74% by the wild parent strain. Similar improvement in degradation of the naphthalene (NAP), phenanthrene (PHE), and benzo (α) pyrene (BAP) was also observed in shuffled strain. The shuffled strain was also able to grow at higher concentration of PAHs and degrade them efficiently. The results indicate that genome shuffling can successfully be used to improve the PAHs degradation capability of bacteria.