title: Enhanced phytoremediation of toxic metals by inoculating endophytic Enterobacter sp. CBSB1 expressing bifunctional glutathione synthase.
abstract: To engineer plant-bacteria symbionts for remediating complex sites contaminated with multiple metals, the bifunctional glutathione (GSH) synthase gene gcsgs was introduced into endophytic Enterobacter sp. CBSB1 to improve phytoremediation efficiency of host plant Brassica juncea. The GSH contents of shoots inoculated with CBSB1 is 0.4μMg(-1) fresh weight. However, the GSH concentration of shoots with engineered CBSB1-GCSGS increased to 0.7μMg(-1) fresh weight. The shoot length, fresh weight and dry weight of seedlings inoculated with CBSB1-GCSGS increased 67%, 123%, and 160%, compared with seedlings without inoculation, respectively. The Cd and Pb concentration in shoots with CBSB1-GCSGS increased 48% and 59% compared with seedlings without inoculation, respectively. The inoculation of CBSB1 and CBSB1-GCSGS could increase the Cd and Pb extraction amounts of seedlings significantly compared with those without inoculation (P<0.05), the seedlings inoculated with CBSB1-GCSGS showed the highest Cd and Pb extraction amounts. It was concluded that the gcsgs gene introduced into Enterobacter sp. CBSB1 upgraded the phytoremediation efficacy of B. juncea. So the engineered Enterobacter sp. CBSB1-GCSGS showed potentials in remediation sites contaminated with complex contaminants by inoculating into remediating plants.
authors.affiliation: School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China.
authors.forename: Zhiqi
authors.initials: Z
authors.lastname: Qiu
authors.affiliation: School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China.
authors.forename: Hongming
authors.initials: H
authors.lastname: Tan
authors.affiliation: School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China.
authors.forename: Shining
authors.initials: S
authors.lastname: Zhou
authors.affiliation: School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China. Electronic address: caolx@mail.sysu.edu.cn.
authors.forename: Lixiang
authors.initials: L
authors.lastname: Cao
mesh_terms: D002104:Cadmium / Q000032:analysis; D060026:Endophytes / Q000201:enzymology*; D004754:Enterobacter / Q000201:enzymology* / Q000235:genetics; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005978:Glutathione / Q000378:metabolism; D005981:Glutathione Synthase / Q000235:genetics / Q000378:metabolism*; D007854:Lead / Q000032:analysis; D009149:Mustard Plant / Q000235:genetics* / Q000378:metabolism; D010944:Plants / Q000378:metabolism*; D010957:Plasmids; D036226:Seedlings; D012989:Soil Pollutants / Q000032:analysis
chemical_list: D012989:Soil Pollutants; D002104:Cadmium; D007854:Lead; D005981:Glutathione Synthase; D005978:Glutathione
keywords: Bioremediation; Endophyte; Glutathione; Metal