Source:
Generated By: https://synbiohub.org/public/igem/igem2sbol/1
Created by: Louise Linnebjerg Bohn Christoffersen, Pernille Marie Madsen, Sheila Maibom-Thomsen
Date created: 2010-10-16 11:00:00
Date modified: 2015-05-08 01:12:08
Flagella master regulating operon
| Types | DnaRegion |
| Roles | CDS Coding |
| Sequences | BBa_K343100_sequence (Version 1) |
Description
The flagella regulon in Escherichia coli is composed of at least 50 genes organized in no less than 14 ope-rons that all contribute to the synthesis and operation of flagella. The operons are synthesized in a three-level transcriptional cascade where the FlhDC operon is the master regulator at the top of the cascade. The flagella regulon is tightly controlled by nutritional and environmental conditions, E. coli starved of ami-no acids showed temporarily decrease of the flagella regulon transcripts which are needed for the synthesis and operation of the flagellum.(1)The synthesis and assembly of flagella are regulated by the transcriptional cascade composed of three levels of gene products (class I, -II and ???III). Class I genes consist of a single operon encoding the proteins FlhD and FlhC that form a multimeric (FlhD4C2) transcriptional activation complex. This ???master regulator??? stimulates transcription by binding upstream of Class II promoters. Class II genes encode proteins that assemble to form the basal body and hook of the flagellum, as well as the fliA gene that encodes the alternative σ factor σ28, also called σF. σ28 binds to RNA polymerase (RNAP) core enzyme and directs it to Class III promoters. Class III genes encode the rest of the structural genes of the flagellum, including fliC encoding flagellin, as well as the chemotaxis apparatus. (1)
It has been shown that overexpression of the FlhDC operon restores motility in mutants that have been made immotile (2). Also, overexpression of FlhDC in the E. coli K12 strain MG1655 made the cells hypermotile.(3)
Notes
This part has an internal pst1 site in the FlhC part of the operon. We also designed a part where the internal pst1 site has been removed by introducing a silent mutation (part: BBa_343000) and a composite part BBa_K343004Source
It is a natural part of the E.coli genome| Sequence Annotation | Location | Component / Role(s) |
| FlhC PstI restriction site FlhD Start codon Start Codon Stop Codon Stop Codon | 359,929 821,821 1,349 1,3 356,358 350,352 930,932 | feature/protein CDS sequence_feature feature/misc CDS feature/protein start_codon feature/start start_codon feature/start stop_codon feature/stop feature/stop stop_codon |