Analysis of new target genes isolated from genome analysis : towards development of new antibiotics

从基因组分析中分离出的新靶基因的分析：迈向新抗生素的开发

• 批准号: 10672107
• 负责人: MORIYA Shigeki
• 金额: $ 1.98万
• 依托单位: Nara Institute of Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10672107/
• 关键词: Bacillus subtilis; Genome; Two-component system; Essential gene; SUA5 family; yycF; 細胞分裂; ftsZ; 増殖必須遺伝子

I have examined functions of two new genes, yycFG and ywlC, essential for call growth of Bacillus subtilis. The gene products could be good targets for new antibiotics because of their newness and essentiality.1.yycF and yycG : The yycF gene encoding a response regulator of a two-component regulatory system was reported recently to be essential for the cell growth, although genes under their control have yet to be identified (Fabret & Hoch, 1998). We also noted the essential nature of the yycF regulator gene and its cognate kinase gene, yycG, in B.subtilis during the course of construction of a knockout mutant bank of the newly identified genes in the genome sequence project. In addition, we found production of mini-cells and reduction in cell length when the YycF regulator was overproduced in B.subtilis. These observations led to the finding that YycF overproduction up-regulated the expression from the P1 promoter of the cell division operon, ftsAZ. In addition, the YycF protein binds to the P1 promoter region in vitro. These results clearly indicate that the essential two-component regulatory system encoded by yycF and yycG genes has the potential to modulate expression of the ftsAZ operon in B.subtilis.2.ywlC : This gene belongs to the SUA5 family that is conserved in eubacteria and yeast but its function is unknown. As a disruption mutant yeast SUA5 gene is known not to grow in a medium containing lactate as the carbon source, we tested the possibility in B.subtilis under depletion of the YwlC protein. Cells could grow under the condition, suggesting that B.subtilis ywlC functions differently from yeast SUA5. Interestingly, it was also found that transcription of ywlC was repressed by DnaA, a key factor of initiation of chromosome replication.

我研究了两个新基因yycFG和ywlC的功能，这两个基因对枯草芽孢杆菌的CALL生长至关重要。这些基因产物可能成为新抗生素的良好靶点，因为它们的新颖性和重要性。1.yycF和yycG：最近有报道称，编码两组分调控系统的反应调节器的yycF基因对细胞生长至关重要，尽管它们控制的基因尚未确定(Fabret&Hoch，1998)。我们还注意到在构建基因组序列计划中新发现的基因敲除突变库的过程中，枯草杆菌中yycF调节基因及其同源激酶基因yycG的基本性质。此外，我们还发现当YycF调节剂在枯草杆菌中过量生产时，会产生微型细胞，并使细胞长度缩短。这些观察导致发现YycF的过量生产上调了细胞分裂操纵子ftsAZ的P1启动子的表达。此外，YycF蛋白在体外与P1启动子区域结合。这些结果清楚地表明，yycF和yycG基因编码的基本双组分调控系统具有调节枯草杆菌中ftsAZ操纵子表达的潜力。2.ywlC：该基因属于SUA5家族，在真细菌和酵母中保守，但其功能尚不清楚。由于已知的突变酵母SUA5基因不能在以乳酸为碳源的培养基中生长，我们测试了枯草杆菌在YwlC蛋白缺失的情况下生长的可能性。在此条件下细胞可以生长，这表明枯草杆菌ywlC的功能与酵母SUA5不同。有趣的是，还发现ywlC的转录被Dna A抑制，Dna A是启动染色体复制的关键因子。