Tuesday, May 1, 2012
Napoleon Ballroom C-D, 3rd fl (Sheraton New Orleans)
A new medium chain length polyhydroxyalkanoate (mcl-PHA) producing bacterium was isolated from wastewater. 16S rRNA, cpn60, and recA gene sequence analyses were used to determine that this isolate was a novel strain of Pseudomonas putida. The novel isolate, P. putida LS46, produced 22-56% cell dry weight of mcl-PHAs from glucose or saturated fatty acids under batch culture conditions. Complete sequence analysis of P.putida LS46 genome revealed a genome size of 5.95 Mbp. Analysis of 28 house-keeping genes of P. putida LS46 indicated 94-100% homology with the corresponding genes from P. putida strains KT2440, F1, GB-1, BIRD-1, and W619. The genes associated with PHA production (pha, fab and fad genes) of P. putida LS46 had 92-100% homology with the other five strains. The three gene (recN, thdF and rpoA) model proposed by Zeigler (2003) was used to predict genome relatedness of P. putida LS46 with other P. putida strains and Pseudomonas species. The results indicated that P. putida LS46 was most closely related to P. putida F1 and BIRD-1.It was also closely related to a mcl-PHAs producer P. entomophila, which was isolated from fruitfly. Genomic Island Viewer identified a number of genomic islands, which were either acquired from closely related P. putida strains or from P. aeruginosa. One of the genomic island encoded for Type VI secretion system, which was also present in P. putida GB-1. Genome analysis of P. putida LS46 indicated that core and accessory genes for mcl-PHA production are highly conserved among P. putida isolated from different niches and geographical regions.