title: A UPF0118 family protein with uncharacterized function from the moderate halophile Halobacillus andaensis represents a novel class of Na+(Li+)/H+antiporter.
abstract: In this study, genomic DNA was screened from Halobacillus andaensis NEAU-ST10-40Tby selection in Escherichia coli KNabc lacking three major Na+/H+antiporters. One gene designated upf0118 exhibiting Na+(Li+)/H+antiport activity was finally cloned. Protein alignment showed that UPF0118 shares the highest identity of 81.5% with an unannotated gene encoding a protein with uncharacterized protein function belonging to UPF0118 family from H. kuroshimensis, but shares no identity with all known specific Na+(Li+)/H+antiporter genes or genes with Na+(Li+)/H+antiport activity. Growth test, western blot and Na+(Li+)/H+antiport assay revealed that UPF0118 as a transmembrane protein exhibits pH-dependent Na+(Li+)/H+antiport activity. Phylogenetic analysis indicated that UPF0118 clustered with all its homologs belonging to UPF0118 family at a wide range of 22-82% identities with the bootstrap value of 92%, which was significantly distant with all known specific single-gene Na+(Li+)/H+antiporters and single-gene proteins with the Na+(Li+)/H+antiport activity. Taken together, we propose that UPF0118 should represent a novel class of Na+(Li+)/H+antiporter. To the best of our knowledge, this is the first report on the functional analysis of a protein with uncharacterized protein function as a representative of UPF0118 family containing the domain of unknown function, DUF20.
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Ping
authors.initials: P
authors.lastname: Dong
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Lidan
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Na
authors.initials: N
authors.lastname: Song
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Lina
authors.initials: L
authors.lastname: Yang
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Jin
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Mingxue
authors.initials: M
authors.lastname: Yan
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Huiwen
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Jincheng
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Heba
authors.initials: H
authors.lastname: Abdel-Motaal
authors.affiliation: Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, Harbin, 150030, PR China.
authors.forename: Juquan
authors.initials: J
authors.lastname: Jiang
mesh_terms: D000595:Amino Acid Sequence; D017920:Antiporters / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D003001:Cloning, Molecular; D058678:Halobacillus / Q000235:genetics / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D017136:Ion Transport; D008094:Lithium / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012964:Sodium / Q000378:metabolism; D017923:Sodium-Hydrogen Exchangers / Q000235:genetics / Q000378:metabolism
chemical_list: D017920:Antiporters; D001426:Bacterial Proteins; D008565:Membrane Proteins; D017923:Sodium-Hydrogen Exchangers; D008094:Lithium; D012964:Sodium