title: Identification of a chitinase-producing bacterium C4 and histopathologic study on locusts.
abstract: In order to develop the potential of chitinase-producing micro-organisms as biocontrol agents for insect pests, five chitinase-producing bacterial strains (C1, C2, C3, C4 and C5) previously isolated from soil samples were chosen to infect grassland locusts. The data showed that the mortality rate of locusts fed with strain C4 was significantly higher than that of other groups, and its pathogenicity was confirmed by Koch's law. Midgut tissues of locusts infected with C4 were examined with a light microscope. Apparent histopathologic changes in midgut cells partly explained the pathogenesis of locusts. Therefore, strain C4 was considered to be a potential biocontrol agent. To determine the taxonomic position of C4, physiological and biochemical characteristics were determined and molecular identification was performed. The 16S rDNA gene of C4 was amplified, cloned and sequenced. Comparative sequence analysis demonstrated that C4 corresponded to the genera Sanguibacter, Oerskovia and Cellulomonas. On the basis of phenotypic characterization and sequence similarity analysis, strain C4 was more closely related to the genus Sanguibacter. This chitinase-producing strain C4, which closely corresponds to the species of the genus Sanguibacter and is pathogenic to locusts, is here reported for the first time.
authors.affiliation: National Laboratory of Grassland Biocontrol Engineering, Sichuan University, Chendu 610064, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Yong
authors.forename: Long
authors.initials: L
authors.lastname: Zhangfu
authors.forename: Xie
authors.initials: X
authors.lastname: Jing
authors.forename: Jin
authors.initials: J
authors.lastname: Hong
authors.forename: Ran
authors.initials: R
authors.lastname: Hongyan
authors.forename: Tao
authors.initials: T
authors.lastname: Ke
authors.forename: Ge
authors.initials: G
authors.lastname: Shaorong
authors.forename: Liu
authors.initials: L
authors.lastname: Kun
authors.forename: Liu
authors.initials: L
authors.lastname: Shigui
mesh_terms: D000192:Actinomycetales / Q000145:classification / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D000818:Animals; D001413:Bacillus thuringiensis / Q000502:physiology; D002688:Chitinases / Q000096:biosynthesis*; D004269:DNA, Bacterial / Q000737:chemistry; D004275:DNA, Ribosomal / Q000737:chemistry; D004064:Digestive System / Q000382:microbiology; D005798:Genes, Bacterial; D016680:Genome, Bacterial; D006110:Grasshoppers / Q000382:microbiology*; D008969:Molecular Sequence Data; D010572:Pest Control, Biological / Q000379:methods*; D010641:Phenotype; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012988:Soil Microbiology; D013045:Species Specificity
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D002688:Chitinases