title: Overexpression of AaPal, a peptidoglycan-associated lipoprotein from Alkalomonas amylolytica, improves salt and alkaline tolerance of Escherichia coli and Arabidopsis thaliana.
abstract: The outer membrane lipoprotein, Pal, plays a major role maintaining the integrity of outer membrane and cell morphology in Gram-negative bacteria. Here, we represent A novel role of AaPal in tolerance to salt and alkaline stresses. The cell density of Escherichia coli expressing AaPal was approx. three times as that of control strain when grown in the presence of 1 M NaCl or at pH 9.0 for 14 h, and transgenic Arabidopsis thaliana grew taller and stronger than wild-type plants when subjected to 200 mM NaCl or pH 9.0 stress. This tolerance was attributed to higher concentrations of K(+) and lower concentrations of Na(+) in the transgenic organism. Our study provides a potential use of AaPal in the improvement of salt and alkaline tolerance in bacteria and plants.
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No.1 West Beichen Road, Chaoyang District, Beijing, 100101, People's Republic of China, zhailei@im.ac.cn.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhai
authors.forename: Yanfen
authors.initials: Y
authors.lastname: Xue
authors.forename: Yuehao
authors.initials: Y
authors.lastname: Song
authors.forename: Mingjie
authors.initials: M
authors.lastname: Xian
authors.forename: Liang
authors.initials: L
authors.lastname: Yin
authors.forename: Naiqin
authors.initials: N
authors.lastname: Zhong
authors.forename: Guixian
authors.initials: G
authors.lastname: Xia
authors.forename: Yanhe
authors.initials: Y
authors.lastname: Ma
mesh_terms: D000468:Alkalies / Q000633:toxicity*; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology*; D029968:Escherichia coli Proteins; D015870:Gene Expression; D006863:Hydrogen-Ion Concentration; D008074:Lipoproteins / Q000096:biosynthesis* / Q000235:genetics; D008969:Molecular Sequence Data; D009997:Osmotic Pressure; D010457:Peptidoglycan; D063245:Plant Development; D030821:Plants, Genetically Modified; D017422:Sequence Analysis, DNA; D012965:Sodium Chloride / Q000378:metabolism; D013312:Stress, Physiological
chemical_list: D000468:Alkalies; D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; C031163:ExcC protein, E coli; D008074:Lipoproteins; D010457:Peptidoglycan; D012965:Sodium Chloride