Dourado Manuella Nobrega, Ferreira Anderson, Araújo Welington Luiz, Azevedo João Lúcio, Lacava Paulo Teixeira
Department of Genetics, "Luiz de Queiroz" College of Agriculture, University of São Paulo, Avenida Pádua Dias 11, P.O. Box 83, 13400-970 Piracicaba, SP, Brazil.
Biotechnol Res Int. 2012;2012:759865. doi: 10.1155/2012/759865. Epub 2012 Mar 7.
Methylobacterium strains were isolated from mangrove samples collected in Bertioga, SP, Brazil, from locations either contaminated or uncontaminated by oil spills. The tolerances of the strains to different heavy metals were assessed by exposing them to different concentrations of cadmium, lead, and arsenic (0.1 mM, 0.5 mM, 1 mM, 2 mM, 4 mM, and 8 mM). Additionally, the genetic diversity of Methylobacterium spp. was determined by sequence analysis of the 16S rRNA genes. The isolates from the contaminated locations were grouped, suggesting that oil can select for microorganisms that tolerate oil components and can change the methylotrophic bacterial community. Cadmium is the most toxic heavy metal assessed in this work, followed by arsenic and lead, and two isolates of Methylobacterium were found to be tolerant to all three metals. These isolates have the potential to bioremediate mangrove environments contaminated by oil spills by immobilizing the heavy metals present in the oil.
甲基杆菌菌株是从巴西圣保罗州贝蒂奥加采集的红树林样本中分离出来的，这些样本采集自受石油泄漏污染或未受污染的地点。通过将菌株暴露于不同浓度的镉、铅和砷（0.1 mM、0.5 mM、1 mM、2 mM、4 mM和8 mM）来评估菌株对不同重金属的耐受性。此外，通过对16S rRNA基因进行序列分析来确定甲基杆菌属的遗传多样性。来自受污染地点的分离株被归类，这表明石油可以选择耐受石油成分的微生物，并能改变甲基营养细菌群落。镉是这项研究中评估的毒性最大的重金属，其次是砷和铅，并且发现两株甲基杆菌对所有三种金属都具有耐受性。这些分离株有可能通过固定石油中存在的重金属来对受石油泄漏污染的红树林环境进行生物修复。
