4 - 12 µM
||Bacteria Escherichia coli
||Sourjik V, Berg HC. Binding of the Escherichia coli response regulator CheY to its target measured in vivo by fluorescence resonance energy transfer. Proc Natl Acad Sci U S A. 2002 Oct 1 99(20):12669-74. p.12674 left column top paragraphPubMed ID12232047
|| Scharf, B. E., Fahrner, K. A. & Berg, H. C. (1998) CheZ has no effect on flagellar motors activated by CheY13DK106YW. J. Bacteriol. 180, 5123–5128. Note-CheY13DK106YW is an "unphosphorylated mutant protein"PubMed ID9748445
||P.12669 left column bottom paragraph: "To learn more about the binding of CheY∼P to FliM and about the kinetics of the chemotactic response, [investigators] extended [their] recent analysis of phosphorylation-dependent interactions of CheY with CheZ (ref 9) and measured fluorescence resonance energy transfer (FRET) between cyan fluorescent protein (CFP) fused to the N terminus of FliM (CFP-FliM) and yellow fluorescent protein (YFP) fused to the C terminus of CheY (CheY-YFP). The FRET technique relies on the distance-dependent transfer of energy from an excited donor fluorophore (CFP) to an acceptor fluorophore (YFP) and allows one to monitor changes in protein interactions in real time in vivo (refs 10, 11)."
||p.12674 left column top paragraph: "The total concentration of CheZ in the cell is 4–12µM, depending on strain and growth conditions (primary source), but most of the CheZ is localized to receptor clusters (ref 2), which might justify the lower value for the cytoplasmic concentration."