Isolation and identification of arsenic metabolizing bacteria from Balcova surface thermal water resources

Bacterial arsenic metabolism is a topic of interest in recent years. Heavy metals are abundant in thermal waters. There is little to be known about the arsenic-resistant bacteria isolated from the surface waters contaminated by thermal waters of İzmir Balçova. The aim of this study is to identify these bacteria and apply the arsenic metabolism experiments in the literature in order to obtain prospective data. In this study, twelve bacteria identified which can grow on PCA containing 500 mM arsenate. Isolates which phenotypic characterizations are determinated with Api 50 CH and Api 20 E, identified according to partial 16S rDNA sequence as Rhodococcus sp., Pannonibacter phragmitetus, Micrococcus yunnanensis, Enterobacter sp., Microbacterium sp and other seven isolate identified as Pseudomonas sp. By using LB broth, high value of arsenic MICs detected. For arsenic detoxification genes; arsA PCR products are detected on three strains, arsB PCR products are detected on six strains; ars C PCR products are detected on seven strains; arsD PCR products are detected on eight strains; arsM PCR products are detected on three strains; arsH PCR products are detected on eleven strains; arsR PCR product is detected on only Enterobacter sp. strain L. For respiratory arsenate reductase genes; arrA is detected on Pseudomonas sp. strain I and arrB is detected on five Pseudomonas sp. strains. Silver nitrate experiment is positive for all isolates which can grow on CDM except a Pseudomonas sp. strain G. This study is pioneer in about arsenic metabolism experiments on bacteria which are isolated from Turkey. This study generates data for pointing out micro pollutants and developing methods of arsenic metabolism experiments in literature. Keywords: Balcova, thermal water, surface water, arsenic, bacteria