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Coordination promiscuity guarantees metal substrate selection in transmembrane primary-active Zn2+ pumps.

ABSTRACT: Metal selectivity in P1B-type ATPase pumps appears to be determined by amino acid motifs on their transmembrane helices. We reveal the principles governing substrate promiscuity towards first-, second- and third-row transition metals in a transmembrane Zn2+/Cd2+/Hg2+/Pb2+ P-type ATPase (ZntA), by dissecting its coordination chemistry. Atomic resolution characterization in detergent micelles and lipid bilayers reveals a "plastic" transmembrane metal-binding site that selects substrates by unique and diverse, yet defined, coordination geometries and ligand-metal distances.

SUBMITTER: Gallenito MJ

PROVIDER: S-EPMC6736703 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Coordination promiscuity guarantees metal substrate selection in transmembrane primary-active Zn2+ pumps.

Gallenito Marc J MJ Irvine Gordon W GW Zhang Limei L Meloni Gabriele G

Chemical communications (Cambridge, England) 20190901 73

Metal selectivity in P1B-type ATPase pumps appears to be determined by amino acid motifs on their transmembrane helices. We reveal the principles governing substrate promiscuity towards first-, second- and third-row transition metals in a transmembrane Zn2+/Cd2+/Hg2+/Pb2+ P-type ATPase (ZntA), by dissecting its coordination chemistry. Atomic resolution characterization in detergent micelles and lipid bilayers reveals a "plastic" transmembrane metal-binding site that selects substrates by unique ...[more]

PMID: 31461510

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