NMR Structure of the Sea Urchin (Strongylocentrotus purpuratus) Metallothionein MTA

doi:10.1006/jmbi.1999.2967

Journal of Molecular Biology

Volume 291, Issue 2, 13 August 1999, Pages 417-428

https://doi.org/10.1006/jmbi.1999.2967 Get rights and content

Abstract

The three-dimensional structure of [¹¹³Cd₇]-metallothionein-A (MTA) of the sea urchin Strongylocentrotus purpuratus was determined by homonuclear ¹H NMR experiments and heteronuclear [¹H,¹¹³Cd]-correlation spectroscopy. MTA is composed of two globular domains, an N-terminal four-metal domain of the amino acid residues 1 to 36 and a Cd₄Cys₁₁ cluster, and a C-terminal three-metal domain including the amino acid residues 37 to 65 and a Cd₃Cys₉ cluster. The structure resembles the known mammalian and crustacean metallothioneins, but has a significantly different connectivity pattern of the Cys-metal co-ordination bonds and concomitantly contains novel local folds of some polypeptide backbone segments. These differences can be related to variations of the Cys sequence positions and thus emphasize the special role of the cysteine residues in defining the structure of metallothioneins, both on the level of the domain architecture and the topology of the metal-thiolate clusters.

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^☆: Abbreviations used: MT, metallothionein; MTA, MT isoform A of Strongylocentrotus purpuratus; MTAα, α-domain of MTA; MTAβ, β-domain of MTA; hMT-2, human MT isoform 2; MT-2α, α-domain of MT-2; MT-2β, β-domain of MT-2; MT-1, lobster or blue crab MT isoform 1; MT-1α, α-domain of MT-1; MT-1β, β-domain of MT-1; NMR, nuclear magnetic resonance; NOE, nuclear Overhauser effect; 2D, two-dimensional; NOESY, NOE spectroscopy; COSY, correlation spectroscopy; TOCSY, total correlation spectroscopy; ppm, parts per million; ³J_HNα, vicinal spin-spin coupling constant between the backbone amide proton and the α-proton; ³J_αβ, vicinal spin-spin coupling constant between the α-proton and one of the β-protons; r.m.s.d., root-mean-square deviation

^☆☆: Edited by P. E. Wright

^f1: Present addresses: Dr Yunyuan Wang, Department of Medical Biochemistry, Texas A&M University Health Science Center, College of Medicine, 440 Reynolds Medical Bldg., College Station, TX 77843-1114, USA; Dr Elaine A. Mackay, 1 Caswall Close, Foxley Field, Binfield, Berkshire RG42 4EF, UK

^f2: Corresponding author

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Journal of Molecular Biology

Regular ArticleNMR Structure of the Sea Urchin (Strongylocentrotus purpuratus) Metallothionein MTA☆,☆☆

Abstract

J. Mol. Biol.

J. Mol. Biol.

Methods Enzymol.

Biochem. Bipohys. Res. Commun

J. Biol. Chem.

J. Magn. Reson. ser. A

J. Mol. Biol.

Methods Enzymol.

J. Mol. Graph.

Biochem. Biophys. Res. Commun.

J. Mol. Biol.

Dev. Biol.

J. Biol. Chem.

J. Biol. Chem.

Biochem. Bipohys. Res. Commun.

FEBS Letters

J. Mol. Biol.

J. Magn. Reson.

Methods Enzymol.

Biochim. Biophys. Acta

Neuron

J. Mol. Biol.

A two-dimensional nuclear Overhauser enhancement (2D NOE) experiment for the elucidation of complete proton-proton cross- relaxation networks in biological macromolecules

Biochem. Biophys. Res. Commun.

The program XEASY for computer- supported NMR spectral analysis of biological macromolecules

J. Biomol. NMR

Comparison of the NMR solution structure and the X-ray crystal structure of rat metallothionein-2

Proc. Natl Acad. Sci. USA

High levels of metallothionein messenger RNAs in male germ cells of the adult mouse

Mol. Endocrinol.

A heteronuclear correlation experiment for simultaneous determination of 15N longitudinal decay and chemical exchange rates of systems in slow equilibrium

J. Biomol. NMR

Polypeptide metal cluster connectivities in metallothionein-2 by novel 1H-113Cd heteronuclear two-dimensional NMR experiments

J. Am. Chem. Soc.

Regular Article
NMR Structure of the Sea Urchin (Strongylocentrotus purpuratus) Metallothionein MTA☆,☆☆

A heteronuclear correlation experiment for simultaneous determination of ¹⁵N longitudinal decay and chemical exchange rates of systems in slow equilibrium

Polypeptide metal cluster connectivities in metallothionein-2 by novel ¹H-¹¹³Cd heteronuclear two-dimensional NMR experiments