Detection of 16SRNA Gene variation of bacterial strains isolated from water marsh polluted with oil spills southern of IRAQ

Abstract

Oil spills closer to Marshes and human populations have greater ecological and economic impacts., especially which result of oil spills occurring of drilling oil wells south of Iraq. In this study, ten samples were collected from different zones of ALHammar marsh. The Samples were symboled with the letter W (W1 to W10). The samples were analyzed with GC to detect types of hydrocarbons found in these samples also COD test we’re done to find the values of higher pollution. The result found that sample W6 had the higher volution my measuring total hydrocarbon compound and COD value wow W1 Sambo showed this valuation among all samples. these two samples were chosen to detect types of bacteria. serial dilutions were done to each sample reached 10 5. each dilution was cultured on nutrient agar to observe growth density in each dilution. the result found that the W1 sample contain mixed bacterial growth with a high number of bacterial growths compared with the W6 sample which included less bacterial growth. The W6 samples growth were cultured on blood agar and MacConkey agar in order to detect the type of gram bacteria, bacteria were examined with Vitek 2 to detect strains type, the result showed that the strains were Citrobacter freundii and Bacillus cereus. DNA extraction was done and primers were designated in order to detect fragments of 16SRNA.PCR and electrophoresis were done to detect target fragments which were appeared at 1500pb as product size. Sanger sequences were done for both strains. the results were analyzed with bioinformatic tools genius software The result of Blast nucleotides was showed that new local strains were detected. The accession numbers of two new strains were submitted to GenBank Bacillus cereus IQ2021772 with accession number MZ958640, version MZ958640-1. The second new strain was Citrobacter freundii strain IQ2021771 with accession number MZ958639 and version MZ958639-1. Phylogenetic trees were constructed for both strains, the results of tracked ancestors of these strains found ancestors were isolated from coastal and industrial zones of China.