title: Mutants of Xanthomonas oryzae pv. oryzae deficient in general secretory pathway are virulence deficient and unable to secrete xylanase.
abstract: Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial leaf blight, a serious disease of rice. A virulence- and xylanase-deficient mutant of Xoo was isolated following ethyl methane sulfonate (EMS) mutagenesis. A cosmid clone that restored virulence and xylanase secretion was obtained from a genomic library by functional complementation. Transposon mutagenesis and marker exchange studies revealed genes on the cloned DNA that were required for xylanase production and virulence. Sequence analysis with transposon-specific primers revealed that these genes were homologues of xps F and xps D, which encode components of a protein secretion system in Xanthomonas campestris pv. campestris. Enzyme assays showed xylanase accumulation in the periplasmic space and cytoplasm of the xps F mutant and the complementing clone restored transport to the extracellular space.
authors.affiliation: Centre for Cellular and Molecular Biology, Hyderabad, India.
authors.forename: S K
authors.initials: SK
authors.lastname: Ray
authors.forename: R
authors.initials: R
authors.lastname: Rajeshwari
authors.forename: R V
authors.initials: RV
authors.lastname: Sonti
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D004251:DNA Transposable Elements / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005020:Ethyl Methanesulfonate / Q000494:pharmacology; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D016296:Mutagenesis; D012275:Oryza / Q000382:microbiology*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D020539:Sequence Analysis, Protein; D014774:Virulence / Q000235:genetics; D014974:Xanthomonas / Q000201:enzymology / Q000235:genetics* / Q000472:pathogenicity; D043325:Xylan Endo-1,3-beta-Xylosidase; D014995:Xylosidases / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D026901:Membrane Transport Proteins; C071567:general secretion pathway protein, Xanthomonas campestris; D005020:Ethyl Methanesulfonate; D014995:Xylosidases; D043325:Xylan Endo-1,3-beta-Xylosidase