Site-directed mutagenesis studies of selected motif and charged residues and of cysteines of the multifunctional tetracycline efflux protein Tet(L).
All of the transmembrane glutamates of Tet(L) are essential for tetracycline (TET) resistance, and E397 has been shown to be essential for all catalytic modes, i.e., TET-Me(2+) and Na(+) efflux and K(+) uptake. Loop residues D74 and G70 are essential for TET flux but not for Na(+) or K(+) flux. A cysteineless Tet(L) protein exhibits all activities.
Jin
Jie
J
Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, New York 10029, USA.
Krulwich
Terry A
TA
D017920:Antiporters / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D003545:Cysteine / Q000235:genetics*; D004926:Escherichia coli / Q000378:metabolism; D029968:Escherichia coli Proteins; D005971:Glutamates / Q000378:metabolism; D017136:Ion Transport; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016297:Mutagenesis, Site-Directed; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D013753:Tetracycline Resistance / Q000235:genetics
D017920:Antiporters; D029968:Escherichia coli Proteins; D005971:Glutamates; D008565:Membrane Proteins; C424711:Tet(L) protein, E coli; D012964:Sodium; D003545:Cysteine; D011188:Potassium