TY - JOUR
T1 - Expression of ZntA, a zinc-transporting P1-type ATPase, is specifically regulated by zinc and cadmium
AU - Noll, Meenakshi
AU - Lutsenko, Svetlana
PY - 2000
Y1 - 2000
N2 - All cells have developed various mechanisms to regulate precisely the availability of important micronutrients such as zinc and copper; in many cells, this regulation is mediated by P1-type ATPases. Most of the P1- ATPases have been described very recently, and little is known about their molecular mechanism and regulation. Here, we demonstrate that the expression of ZntA, a Zn,Cd-transporting P-type ATPase of Escherichia coli, is specifically regulated by the transported cations, cadmium and zinc. Nickel, cobalt, and copper did not induce the expression of ZntA, even when present at concentrations as high as 0.6-1 mM. The effect of zinc and cadmium on the ZntA expression is concentration dependent, the apparent K(m) for Cd (19 μM) being markedly lower than that for Zn (100 μM). This metal selectivity is opposite to the known metal selectivity of transport by ZntA. Thus, we speculate that, to maintain zinc concentrations in the cell in the presence of cadmium, ZntA probably interacts with other proteins that modulate the ZntA selectivity towards transported cations.
AB - All cells have developed various mechanisms to regulate precisely the availability of important micronutrients such as zinc and copper; in many cells, this regulation is mediated by P1-type ATPases. Most of the P1- ATPases have been described very recently, and little is known about their molecular mechanism and regulation. Here, we demonstrate that the expression of ZntA, a Zn,Cd-transporting P-type ATPase of Escherichia coli, is specifically regulated by the transported cations, cadmium and zinc. Nickel, cobalt, and copper did not induce the expression of ZntA, even when present at concentrations as high as 0.6-1 mM. The effect of zinc and cadmium on the ZntA expression is concentration dependent, the apparent K(m) for Cd (19 μM) being markedly lower than that for Zn (100 μM). This metal selectivity is opposite to the known metal selectivity of transport by ZntA. Thus, we speculate that, to maintain zinc concentrations in the cell in the presence of cadmium, ZntA probably interacts with other proteins that modulate the ZntA selectivity towards transported cations.
KW - Cadmium
KW - Protein expression
KW - Zinc
KW - ZntA
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U2 - 10.1080/15216540050033168
DO - 10.1080/15216540050033168
M3 - Article
C2 - 10995032
AN - SCOPUS:0033917143
VL - 49
SP - 297
EP - 302
JO - Biochemistry and Molecular Biology International
JF - Biochemistry and Molecular Biology International
SN - 1521-6543
IS - 4
ER -