Laboratory of Bacterial Genetics and Environmental Biotechnology, Department of Microbiology, Goa University, Taleigao Plateau, Goa 403 206, India.
Laboratory of Bacterial Genetics and Environmental Biotechnology, Department of Microbiology, Goa University, Taleigao Plateau, Goa 403 206, India.
Ecotoxicol Environ Saf. 2012 May;79:129-133. doi: 10.1016/j.ecoenv.2011.12.015. Epub 2012 Jan 29.
A bacterial isolate from Mandovi estuary Goa, India, which can resist 0.6mM lead nitrate in Tris-buffered minimal medium was identified as Pseudomonas aeruginosa and designated as strain WI-1. PCR amplification clearly revealed presence of bmtA gene encoding bacterial metallothionein responsible for metal sequestration and AAS analysis proved intracellular bioaccumulation of 26.5mg lead/gram dry weight of cells. SDS-PAGE analysis confirmed lead induced bacterial metallothionein with molecular weight 11 kDa, which corresponds to the predicted bmtA gene. Significant growth inhibition of phytopathogenic fungi Fusarium oxysporum NCIM 1008 by siderophore-rich culture supernatant was also observed. Pot experiment with Pisum sativum L inoculated with this strain revealed higher seed germination percentage and significant growth promotion than uninoculated seeds in a soil amended with 7.704 g/kg lead, which indicates amelioration of lead toxicity. This lead resistant strain showed cross tolerance to cadmium, mercury and Tributyltin chloride (TBTC) along with resistance to multiple antibiotics.
从印度果阿曼多维河口分离出的一株能在 Tris 缓冲最小培养基中耐受 0.6mM 硝酸铅的细菌，被鉴定为铜绿假单胞菌，并被命名为 WI-1 株。PCR 扩增清楚地显示出编码细菌金属硫蛋白的 bmtA 基因的存在，该基因负责金属螯合，AAS 分析证明细胞内生物积累了 26.5mg 铅/克干重。SDS-PAGE 分析证实了诱导细菌金属硫蛋白的存在，分子量为 11kDa，与预测的 bmtA 基因相对应。还观察到富含铁载体的培养液对植物病原菌尖孢镰刀菌 NCIM 1008 的显著生长抑制作用。用该菌株接种豌豆的盆栽试验表明，与未接种种子相比，在添加了 7.704g/kg 铅的土壤中，种子发芽率更高，生长明显促进，表明铅毒性得到了缓解。这种耐铅菌株对镉、汞和三丁基锡氯化物（TBTC）表现出交叉耐受性，同时还对多种抗生素表现出耐药性。
