- 作者: Jia-Hurng Liu; Meng-Jiun Lai; Sunny Ang; Jwu-Ching Shu; Po-Chi Soo; Yu-Tze Horng; Wen-Ching Yi; Hsin-Chih Lai; Kwen-Tay Luh; Shen-Wu Ho; Simon Swift
- 作者服務機構: School and Graduate Institute of Medical Technology, College of Medicine, National Taiwan University, Departmet of Laboratory Medicine, National Taiwan University Hospital, Taipei, Taiwan, ROC; Institute of Infections and Immunity, University of Nottingham, Queen's Medical Centre, School of Pharmaceutical Sciences, University Park, Nottingham, UK
- 中文摘要: --
- 英文摘要: We investigated in Serratia marcescens the functions ofthe fIhDC operon, which controls motility and cell divi-sion in enteric bacteria. lncluded in our evaluations wereinvestigation of cell division, flagellar synthesis and reg-ulation of the expression of nuclease (encoded by thenucAsm gene, one of the virulence factors). Interruptionof the chromosomal fIhDC operon in S. marcescensCH-1resulted in aberrant cell division and loss of nuclease andflagella. Expression of nucAsm and other mutated pheno-types was restored in the fIhDC mutant by the inductionof overexpression of fIhDCin a multicopy plasmid. Multi-copied flhDCalso induced the formation of differentiatedcells (polyploid aseptate cells with oversynthesis of peri-trichous flagella) in broth culture using minimal growthmedium. Expression of the fIhDC operon showed posi-tive autoregulation, and was growth phase dependent(upregulated in early log phase). In addition, fIhDC ex-pression was inhibited when the temperature increasedfrom 30 to 37'C, and when osmolarity was increased,but was not influenced by glucose catabolite repression.These results show that FlhD/FlhC is a multifunctionaltranscriptional activator involved in the process of celldifferentiation, swarming and virulence factor expres-sion.
- 中文關鍵字: --
- 英文關鍵字: --