1Fish Microbiology Division, Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar - 751002, Orissa, India
2Fish Genetics & Biotechnology Division, Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar - 751002, Orissa, India
*Corresponding author; E-mail: maitink@yahoo.co.in Tel: 91 674 2465421
Restriction fragment length polymorphism (RFLP) of 16S rDNA PCR product was carried out for 41 isolates of Pseudomonas spp. isolated from freshwater culture systems. Twenty 16s rDNA genotypes were obtained by digestion with three restriction enzymes (Alu I, Hae III and Msp I). Genomic diversity was observed at both inter-and intra-species level Out of three restriction enzymes, Hae III was found to be most discriminatory and Alu I was least. The most prevalent genotype comprised of 11 P. aeruginosa. Some isolates were exclusively found to be season specific. No habitat specific genotype was observed. To estimate the genetic relationship 31 user-defined bins were scored by their presence or absence. A dendogram was constructed by UPGMA. Forteen groups were obtained. Group1 was the largest and included 53% of the total isolates studied. The reference strains were grouped separately, except P. fluorescens which was clustered with B. cepacia isolated from water.
PCR, 16S rDNA, RFLP, genotypes, Pseudomonas spp.
