title: SecG is required for antibiotic activities of Pseudomonas sp. YL23 against Erwinia amylovora and Dickeya chrysanthemi.
abstract: Strain YL23 was isolated from soybean root tips and identified to be Pseudomonas sp. This strain showed broad-spectrum antibacterial activity against bacterial pathogens that are economically important in agriculture. To characterize the genes dedicated to antibacterial activities against microbial phytopathogens, a Tn5-mutation library of YL23 was constructed. Plate bioassays revealed that the mutant YL23-93 lost its antibacterial activities against Erwinia amylovora and Dickeya chrysanthemi as compared with its wild type strain. Genetic and sequencing analyses localized the transposon in a homolog of the secG gene in the mutant YL23-93. Constitutive expression plasmid pUCP26-secG was constructed and electroporated into the mutant YL23-93. Introduction of the plasmid pUCP26-secG restored antibacterial activities of the mutant YL23-93 to E. amylovora and D. chrysanthemi. As expected, empty plasmid pUCP26 could not complement the phenotype of the antibacterial activity in the mutant. Thus the secG gene, belonging to the Sec protein translocation system, is required for antibacterial activity of strain YL23 against E. amylovora and D. chrysanthemi.
authors.affiliation: Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, China; Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Mississippi State, MS, USA.
authors.forename: Youzhou
authors.initials: Y
authors.lastname: Liu
authors.forename: Sonya M
authors.initials: SM
authors.lastname: Baird
authors.forename: Junqing
authors.initials: J
authors.lastname: Qiao
authors.forename: Yan
authors.initials: Y
authors.lastname: Du
authors.forename: Shi-En
authors.initials: SE
authors.lastname: Lu
mesh_terms: D000900:Anti-Bacterial Agents / Q000378:metabolism*; D000898:Antibiosis; D016000:Cluster Analysis; D004252:DNA Mutational Analysis; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D016974:Dickeya chrysanthemi / Q000187:drug effects / Q000254:growth & development*; D044084:Erwinia amylovora / Q000187:drug effects / Q000254:growth & development*; D017353:Gene Deletion; D005816:Genetic Complementation Test; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D010802:Phylogeny; D010957:Plasmids; D011549:Pseudomonas / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000502:physiology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013025:Glycine max / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D026901:Membrane Transport Proteins; D012336:RNA, Ribosomal, 16S
keywords: Antibacterial; Dickeya chrysanthemi; Erwinia amylovora; Pseudomonas sp.; secG