Molecular and cellular biology and development of useful cellular functions of microorganisms which can utilize future-type natural resources

点击翻译按钮获取中文摘要

Among future-type natural resources, we focused on utilization of natural gas-derived-C1-compounds (eg., methanol) and various type of alkanes (gaseous and isoalkanes), by various microorganisms. We tried to understand cellular functions of such microorganisms from three distinct aspects, i.e., biochemisty, cell biology, and molecular biology. Throughout the research, obtained information and reagents were considered for application to biotechnology. Our biochemical research has revealed novel metabolism for bacterial formadehyde-fixation and formaldehyde detoxification, iso-alkane and gaseous alkane oxidation at gene levels (J Bact, 2004, 2005 : FEMS Microbiol 2002). And also, novel detoxification systems against formaldehyde and reactive oxygen speicies were discovered with methanol-utilizing yeasts (JBC 2001 ; J. Bact 2001 ; Yeast 2004 ; Microbiology 2003). Our cellular and morphological studies on methanol-utilizing yeasts have revealed up to 30 molecular machineries for organelle … More (peroxisome) degradation, and identified a previously-unknown intracellular membrane dynamics, e.g., appearance of a novel membrane structure, micropexophagic membrane apparatus (MIPA), as well as novel vacuolar dynamics. These were further studied from the scope of molecular functions of newly-identified ATG gene products (EMBO J 2003 ; Mol Biol Cell 2004, 2005 ; Dev Cell 2003). These studies and obtained reagents were revealed to be useful for production of heterologous proteins by methylotrophic yeasts. Molecular biological research has focused on the regulatory expression of C1-enzymes in bacteria and yeasts. This study identified the first DNA-binding protein HxlR in Bacillus subtilis, which regulates formaldehyde-induced gene expression of formaldehyde-fixation pathway (Mol Microbiol 2005). And we also developed a novel formaldehyde- or formate-inducible promoter and valuable hosts with methanol-utilizing yeasts (Mol Gen Genet 2003). Using these reagents, we have succeeded in high level production of several useful proteins in an active form (Biosci Biotechnol Biochem 2002, 2003, 2004 ; Appl Microbiol Technol 2002.) Less