HIRATA Hajime Himeji Institute of Technology, Faculty of Science, Prof., 理学部, 教授 (40049052)
KURAZONO Hisao Okayama University, Medical Technology, Prof., 医学部・保健学科, 教授 (90186487)
HAYASHI Hideo University of Tsukuba, Basic Medical Sciences, Proff., 基礎医学系, 教授 (40033203)
|Budget Amount *help
¥3,200,000 (Direct Cost : ¥3,200,000)
Fiscal Year 1999 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 1998 : ¥2,000,000 (Direct Cost : ¥2,000,000)
1. Promoter assay using luciferase reporter revealed that P1 promoter of HSP70 operon was the strongest of all promoters. Both P1 promoter of HSP70 operon and HSP60 operon promoter involved the CIRCE (Controlling Inverted Repeat of Chaperon Expression) element. Disruption and complementation of orf37 showed the transcripts from those CIRCE dependent promoters were repressed by ORF37 over-products, nevertheless the transcripts from the CIRCE independent promoters were not affected in this case. Additionally, gel retardation assay and Atomic Force Microscopy (AFM) with a specific CIRCE probe revealed that the ORF37 should be involved in the CIRCE dependent repression for heat induction.
2. Resistance to heavy metals such as arsenate, cadmium, and mercury has been found in a number of Staphylococcus aureus strains. These resistance has been encoded in plasmids, but not chromosomal. Here we report that one of the S. aureus 912 genomic library were positively induced by heat, cadmium, mercur
y and zinc insults, using differential hybridization analysis. DNA sequencing and Northern analysis revealed that 1.4 kb transcript containing two open reading frames was induced by heat and metal insults, and the genes were named czr (Cadmium and Zinc Responsible gene) operon.
3. A novel gene, drp35, of Staphylococcus aureus, that was inducible especially with cell wall-affecting antibiotics, has been cloned. Analysis of differential hybridization with mRNAs enhanced in the presence of beta-lactams resulted in two positive clones that harbored a new gene encoding 35,845-Da protein (Drp35) and the penicillin-binding protein 2 (PBP2). The gene targeting experiments revealed that the Drp35 involved in transport of beta-lactamase across the cell membrane and expressed the resistance to beta-lactams.
4. A novel oxidative stress genes qorAB, that was heat-inducible, has been cloned. Their transcriptional products were induced especially with oxidative reagents (HィイD22ィエD2OィイD22ィエD2 and Menadione).
5. To clarify regulation upon sigma factor (sigB), the gene targeting experiments revealed that the alkaline response genes (asp operon), the yellow pigment genes, and the gene regulator (agr operon) for toxin-producing, were controlled.
6. Genome analysis for MRSA strain has been going.