Open AccessMutants of Xanthomonas oryzae pv. oryzae Deficient in General Secretory Pathway Are Virulence Deficient and Unable to Secrete Xylanase
Author(s) -
Suvendra Kumar Ray,
R. Rajeshwari,
Ramesh V. Sonti
Publication year - 2000
Publication title -
molecular plant-microbe interactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.565
H-Index - 153
eISSN - 1943-7706
pISSN - 0894-0282
DOI - 10.1094/mpmi.2000.13.4.394
Subject(s) - xanthomonas oryzae , virulence , transposon mutagenesis , biology , xanthomonas oryzae pv. oryzae , cosmid , xanthomonas campestris , microbiology and biotechnology , mutant , xylanase , transposable element , mutagenesis , gene , genetics , biochemistry , pathogen , enzyme
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. Trans-poson mutagenesis and marker exchange studies revealed genes on the cloned DNA that were required for xylanase production and virulence. Sequence analysis with trans-poson-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.