title: Magnesium uptake of Arabidopsis transporters, AtMRS2-10 and AtMRS2-11, expressed in Escherichia coli mutants: Complementation and growth inhibition by aluminum.
abstract: Magnesium (Mg2+) plays a critical role in many physiological processes. Mg2+ transport systems in Salmonella have been well documented, but those in Escherichia coli have not been fully elucidated. We examined the effects of corA, mgtA, yhiD and corC gene deletion on Mg2+ transport in E. coli. We obtained every combination of double, triple and quadruple mutants. The corA and mgtA double mutant required addition of 10 mM Mg2+ to Luria-Bertani (LB) medium for growth, and the corA, mgtA and yhiD triple mutant TM2 required a higher Mg2+ concentration. The Mg2+ requirement of the quadruple mutant was similar to that of TM2. The results demonstrated that either CorA or MgtA is necessary for normal E. coli growth in LB medium and that YhiD plays a role in Mg2+ transport under high Mg2+ growth conditions in E. coli. The Arabidopsis Mg2+ transporters, AtMRS2-10 and AtMRS2-11, were heterologously expressed in TM2 cells. TM2 cells expressing AtMRS2-10 and AtMRS2-11 could grow in LB medium that had been supplemented with 1 mM Mg2+ and without Mg2+ supplementation, respectively, and cell growth was inhibited by 2 mM AlCl3. The results indicated that the growth of TM2 expressing AtMRS2-10 and AtMRS2-11 reflected these AtMRS2 function for Mg2+ and aluminum. The E. coli TM2 cells are useful for functional analysis of Arabidopsis MRS2 proteins.
authors.affiliation: Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo-ku, Kyoto 606-8522, Japan. Electronic address: ishijima@kpu.ac.jp.
authors.forename: Sumio
authors.initials: S
authors.lastname: Ishijima
authors.affiliation: Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo-ku, Kyoto 606-8522, Japan.
authors.forename: Misaki
authors.initials: M
authors.lastname: Uda
authors.affiliation: Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo-ku, Kyoto 606-8522, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Hirata
authors.affiliation: Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo-ku, Kyoto 606-8522, Japan.
authors.forename: Makiko
authors.initials: M
authors.lastname: Shibata
authors.affiliation: Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo-ku, Kyoto 606-8522, Japan.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Kitagawa
authors.affiliation: Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Sakyo-ku, Kyoto 606-8522, Japan.
authors.forename: Ikuko
authors.initials: I
authors.lastname: Sagami
mesh_terms: D000535:Aluminum / Q000633:toxicity*; D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D003470:Culture Media / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D005816:Genetic Complementation Test; D008274:Magnesium / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism*; D009154:Mutation; D014170:Transformation, Genetic / Q000187:drug effects
chemical_list: D029681:Arabidopsis Proteins; D003470:Culture Media; D026901:Membrane Transport Proteins; D000535:Aluminum; D008274:Magnesium
keywords: Aluminum; Arabidopsis thaliana; Deletion mutant; Escherichia coli; MRS2; Magnesium transport