Int.J.Curr.Microbiol.App.Sci (2014) 3(5): 680-690 680 Original Research Article Phylogenetic heterogeneity of the rhizospheric soil bacterial isolates producing PHAs revealed by comparative analysis of 16s-rRNA S.Mohapatra, D. P.Samantaray* and S.M.Samantaray Department of Microbiology, OUAT, Bhubnaneswar-751003, Odisha, India *Corresponding author ABSTRACT Introduction Growth in the human population has lead to the accumulation of huge amounts of non-degradable waste materials across our planet. The accumulation of plastic wastes has become a major concern in terms of the environment (Guillet, 2002; Derraik, 2002; Thompson et al., 2004). Conventional plastics not only take many decades to be decomposed in nature, but also produce toxins during the process of degradation. For this reason, there is special interest in producing biopolymer that can be readily eliminated from our biosphere in an environmentally friendly fashion (Gross and Kalra, 2002). Poly- hydroxyalkanoates (PHAs) are the boipolymer produced and accumulated in prokaryotes as carbon and energy storage materials (Rehm, 2003). They are water insoluble polymers and stored in the cell ISSN: 2319-7706 Volume 3 Number 5 (2014) pp. 680-690 http://www.ijcmas.com Keywords Rhizospheric; Hydrophobic inclusions; Bacillus sp. Polyhydroxyalkanoates (PHAs) are gaining more importance over the world due to their structural diversity, close analogy to plastics and their biodegradability which makes them extremely desirable substitutes for synthetic plastics. PHAs are produced by various microorganisms under certain stress conditions. In this study, 78 bacteria were isolated from rhizospheric soil region of different plants growing in Odisha and screened for presence of PHAas hydrophobic inclusions in the cytoplasm. Out of all, 16 bacterial isolate showed presence of PHAs granule. All the PHA producing bacterial isolates were identified by molecular characterisation to study the evolutionary relationships. These 16 strains were characterized by sequencing partial 16s rRNA gene and belong to genus Bacillus such as Bacillus flexus strain MRK13, Bacillus sp.S4(2013b), Bacillus sp. P1(2013b), Bacillus sp. S1(2013b), Bacillus sp. S6(2013b), Bacillus sp. O1, Bacillus sp. P2(2013), Bacillus sp. P3(2013), Bacillus sp. P4(2013c), Bacillus sp. B2(2013c), Bacillus sp. B5(2013b), Bacillus sp. C1(2013), Bacillus sp. C3(2013), Bacillus sp. O6, Bacillus sp. S8, Bacillus thuringiensis strain RKD12. The nucleotide sequence submitted have been appear in the GenBank database under accession numbers KF626466 to KF626481. Under optimized condition Bacillus sp. S1 2013b possesses the potential for the production PHA (80.94%) in vitro.