Purification and characterization of the CheZ protein of bacterial chemotaxis.
AUTOR(ES)
Stock, A M
RESUMO
The cheZ gene is the most distal of five genes that comprise the Meche operon of the Salmonella typhimurium chemotaxis system. We have determined the sequence of the cheZ gene along with an 800-nucleotide flanking region at its 3' end. The flanking sequence contains an open reading frame that probably corresponds to the 5' end of flaM. The cheZ coding sequence predicts an extremely acidic, hydrophilic protein with a molecular weight of 23,900. We have purified and characterized this protein. N-terminal analysis of pure CheZ yields an amino acid sequence identical to that predicted by the nucleotide sequence except that the amino-terminal methionine residue is modified by N methylation. The purified CheZ protein exhibits a native molecular weight of 115,000, but in cell extracts the majority of CheZ exists as a much larger aggregate (Mr greater than 500,000). Under these conditions, CheZ appears to be a homopolymer composed of at least 20 monomeric subunits.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=212384Documentos Relacionados
- Signal termination in bacterial chemotaxis: CheZ mediates dephosphorylation of free rather than switch-bound CheY.
- Roles of cheY and cheZ gene products in controlling flagellar rotation in bacterial chemotaxis of Escherichia coli.
- Isolation and Characterization of Nonchemotactic CheZ Mutants of Escherichia coli
- In vivo and in vitro characterization of Escherichia coli protein CheZ gain- and loss-of-function mutants.
- Role of CheW protein in coupling membrane receptors to the intracellular signaling system of bacterial chemotaxis.