Part:BBa_K343100
Native flhDC master regulon
Background
More than 80% of all known bacterial species express flagella [1]. The synthesis of the flagella is a complex and energy consuming process, so the expression of the involved proteins is tightly regulated by the extracellular environment. One of the most well studied flagella synthesis systems is that of Eschericia coli. Here the expression of the master regulator FlhDC operon is controlled i.e. by pH, salt concentration or the availability of nutrients. Apart from initiation of flagella synthesis FlhDC is also a repressor of cell metabolism as cell growth and flagellation does not occur at the same time. FlhDC is a hexameric transcription factor that consists of four FlhD subunits and two FlhC subunits (FlhD4C2). It constitutes the first class in the three classed flagella synthesis cascade. Class II consist of genes encoding proteins that make up the basal body, as well as the alternative transcription factor, σ28, which is responsible for the expression of the class III genes. These genes in turn encodes the proteins that composes the tail filaments.
Studies of insertion elements (IS) upstream of the flhDC operon, has shown that an upregulation of the expression of the operon is responsible for the motility of the E. coli MG1655 strain. [2]It has also been shown that overexpression of the FlhDC operon restores motility in mutants that have been made immotile [3].
Refrences
- O. Soutourina , PN. Bertin [http://www.ncbi.nlm.nih.gov/pubmed/14550943 Regulation cascade of flagellar expression in Gram-negative bacteria.]
- O. Soutourina, A. Kolb, E. Krin, C. Laurent-Winter, S. Rimsky, A. Danchin, and P. Bertin[http://jb.asm.org/cgi/content/short/181/24/7500 Multiple Control of Flagellum Biosynthesis in Escherichia coli: Role of H-NS Protein and the Cyclic AMP-Catabolite Activator Protein Complex in Transcription of the flhDC Master Operon]
- Eric J. Gauger, Mary P. Leatham, Regino Mercado-Lubo, David C. Laux, Tyrrell Conway, and Paul S. Cohen [http://iai.asm.org/cgi/content/abstract/75/7/3315 Role of Motility and the flhDC Operon in Escherichia coli MG1655 Colonization of the Mouse Intestine{triangledown}]
Sequence and Features
- 10INCOMPATIBLE WITH RFC[10]Illegal PstI site found at 821
- 12INCOMPATIBLE WITH RFC[12]Illegal PstI site found at 821
- 21COMPATIBLE WITH RFC[21]
- 23INCOMPATIBLE WITH RFC[23]Illegal PstI site found at 821
- 25INCOMPATIBLE WITH RFC[25]Illegal PstI site found at 821
Illegal AgeI site found at 609 - 1000COMPATIBLE WITH RFC[1000]
Safety
[http://iai.asm.org/cgi/reprint/75/7/3315 Role of Motility and the flhDC Operon in Escherichia coli MG1655 Colonization of the Mouse Intestine]
[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC93725/ The Yersinia enterocolitica Motility Master Regulatory Operon, flhDC, Is Required for Flagellin Production, Swimming Motility, and Swarming Motility]
[http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0008029 Repression of Invasion Genes and Decreased Invasion in a High-Level Fluoroquinolone-Resistant Salmonella Typhimurium Mutant]
None |