Project description:We investigated the virulence and pathogenic related gene expression by performing the transcriptomics analysis of B. thuringiensis serovar kurstaki strain YBT-1520 over a time course, using CombiMatrix (microarray) technique.
Project description:We have developed a strategy for isolating cry genes from Bacillus thuringiensis. The key steps are the construction of a DNA library in an acrystalliferous B. thuringiensis host strain and screening for the formation of crystal through optical microscopy observation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analyses. By this method, three cry genes--cry55Aa1, cry6Aa2, and cry5Ba2--were cloned from rice-shaped crystals, producing B. thuringiensis YBT-1518, which consists of 54- and 45-kDa crystal proteins. cry55Aa1 encoded a 45-kDa protein, cry6Aa2 encoded a 54-kDa protein, and cry5Ba2 remained cryptic in strain YBT-1518, as shown by SDS-PAGE or microscopic observation. Proteins encoded by these three genes are all toxic to the root knot nematode Meloidogyne hapla. The two genes cry55Aa1 and cry6Aa2 were found to be located on a plasmid with a rather small size of 17.7 kb, designated pBMB0228.
Project description:To determine Sigma 54 (SigL) reglons in Bacillus thuringiensis HD73 strain, A sigLmutant, HD(ΔsigL::kan), was constructed with insertion of kanamycin resistance gene cassete. We have employed whole genome microarray expression profiling as a discovery platform to identify the difference of gene expression between mutant and wild-type strains.