Premium
The membrane‐located osmosensory kinase, EnvZ, that contains a leucine zipper‐like motif functions as a dimer in Escherichia coli
Author(s) -
Yaku Hidenobu,
Mizuno Takeshi
Publication year - 1997
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(97)01329-x
Subject(s) - leucine zipper , bzip domain , biochemistry , periplasmic space , dimer , histidine , cysteine , leucine , basic helix loop helix leucine zipper transcription factors , escherichia coli , chemistry , peptide sequence , biology , amino acid , dna binding protein , transcription factor , enzyme , organic chemistry , gene
The Escherichia coli EnvZ protein is a membrane‐located osmosensor, which is a typical member of histidine kinases involved in His‐Asp phosphotransfer signaling. We found that EnvZ has a leucine zipper‐like motif in its presumed periplasmic domain. The functional importance of this leucine zipper‐like sequence was assessed by introducing a number of appropriate amino acid substitutions. The results collectively suggest that certain leucine residues in the leucine zipper‐like structure play an important role in the osmotic signal transduction mediated by EnvZ. When cysteine was substituted for the crucial leucine residues, the EnvZ dimer with disulfide bridge was detected in the cytoplasmic membrane. It was thus demonstrated that the EnvZ osmosensor exists and exerts its signaling ability as a dimer.