Molecular identification of Rhodopseudomonas palustris isolated from soil in waste dump site in Minna metropolis

Abstract

Rhodopseudomonas palustris, is a purple non-sulphur bacterium with properties of extraordinary metabolic versatility, carbon source diversity and metabolite diversity. Due to its biodetoxification and biodegradation properties, R. palustris has been traditionally applied in wastewater treatment and bioremediation, and also in agriculture. This study aimed to isolate and identify R. palustris from waste dump site in Minna, Nigeria, using conventional and molecular techniques. Soil samples were collected at 3 cm depth from different points at waste dump sites in Minna, Niger State, Nigeria. Inoculation was made on Nutrient agar plates and incubated at 30 ºC under 60 W incandescent light for 7days. The suspected bacterial isolate, based on cultural and morphological characteristics as well as biochemical reactions was subjected to molecular ribotyping. A PCR product of approximately 789 bp DNA maker was detected by agarose gel electrophoresis using 1500 bp Lamda maker. The DNA fragments of the isolates were obtained from DNA sequencing and were deposited in the NCBI-GenBank database. Based BLASTn search in GenBank using the fragments as the query, showed that the 16S rDNA of EG-4 share 99% sequence identity with Rhodopseudomonas palustris. Results of this study indicate the presence of R. palustris in waste dump site in Minna.