[2] Cadmium-113 nuclear magnetic resonance applied to metalloproteins

Je, Coleman

doi:10.1016/0076-6879(93)27004-z

Cited by 65 publications

(30 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Based on the chain molecular weight obtained by gel SDS-PAGE electrophoresis the three clam CdMTs isolated bind a total of six to eight cadmium atoms (Table 1). This results of stoichiometry metal/chain of MT confirm the existence of a cluster identical to the one suggested for others MTs isolated and structurally characterised (Coleman, 1993).…”

Section: Discussionsupporting

confidence: 88%

Isolation and characterisation of metallothionein from the clam Ruditapes decussatus

2003

View full text Add to dashboard Cite

Metallothioneins (MT) were obtained after purification from metal-exposed clams (Ruditapes decussatus ) using gelpermeation and ion-exchange chromatography. Four cadmium Á/metallothioneins (CdMTs) were resolved by ionexchange chromatography and they all had similar molecular weights, high cadmium content and an absorption spectra indicative of the presence of characteristic Cd Ã/S aggregates. The NH 2 -terminal sequence suggests the presence of at least two class I clam MT isoforms. For the other two putative clam CdMTs isolated, the results of the amino acid determination were inconclusive. One was slightly contaminated and the other one had a blocked NH 2 -terminal. These clam metalothioneins contain glycine, which seems to be a common feature of molluscan MT family and exhibited more similarity to oysters than to mussels. Further investigation on the inducibility of these isoforms will be necessary if clams are to be used as biomarkers of metal exposure. #

show abstract

Section: Discussionsupporting

confidence: 88%

Isolation and characterisation of metallothionein from the clam Ruditapes decussatus

2003

View full text Add to dashboard Cite

show abstract

“…The chemical shifts of the two "'Cd NMR signals of Il3Cd2UME6(1 1 I ) at 5 "C (699 and 689 ppm) are within the range of chemical shifts found for "'Cd ions coordinated to four -S-ligands, based on the correlation of chemical shift with type and number of donor atoms derived from 'I3Cd-substituted protein sites of known donor composition (Coleman, 1993).…”

Section: Discussionmentioning

confidence: 99%

“…Although exchange broadening of ll3Cd resonances has been described for several '13Cd-substituted Zn proteins (Coleman, 1993), the room temperature exchange broadening of the signal from one of the two "'Cd ions in UME6(111) is the first -S4 site where exchange broadening is sufficient to render the resonance undetectable at room temperature. The exchange process must be a conformational flux of the protein transmitted to the "'Cd environment rather than metal ion dissociation, because the stoichiometry of the complex remains 2 Cd/mol of protein after a 24-h dialysis at 25 "C. If a dissociated metal ion species were the second species in a chemical exchange with the protein-bound 'I3Cd, then its population would have to be at least 10% of the total in order to significantly broaden the signal of the bound 'I3Cd (Coleman et al, 1979).…”

Section: Discussionmentioning

confidence: 99%

UME6, a negative regulator of meiosis insaccharomyces cerevisiae, contains a C-terminal Zn₂Cys₆binuclear cluster that binds the URS1 DNA sequence in a zinc-dependent manner

et al. 1995

View full text Add to dashboard Cite

UME6 is a protein of 836 amino acids from Saccharomyces cerevisiae that acts as a repressor and activator of several early meiotic genes. UME6 contains, near the C-terminus, the amino acid sequence "7'c-x~-c-x6-c-x6-C-X,-C-X,-C-, in which the spacings of the six Cys residues are identical to those found in 39 N-terminal Cysrich DNA binding subdomains of fungal transcription factors. This sequence has been shown in GAL4 and other proteins to form a zinc binuclear. cluster. In spite of the different location, the C-rich sequence, cloned and overproduced within the last 11 1 amino acid residues of UME6, UME6(11 I), forms a binuclear cluster and exhibits a Zn-dependent binding to the URSl DNA sequence. The latter, TAGCCGCCGA, is required for the repression or activation of meiosis-specific genes by UME6. UME6(111) contains 1.8 k 0.4 mol Zn/mol protein and the Zn can be exchanged for Cd to yield a protein containing 1.9 k 0.1 mol Cd/mol protein.At 5 "C, 1'3Cd2UME6(l 11)shows two Il3Cd NMR signals, with chemical shifts of 699 and 689 ppm, similar to those observed for "3CdzGAL4(149). The magnitude of these chemical shifts suggests that each 'I3Cd nucleus is coordinated to four -S-ligands, compatible with a II3Cdz cluster structure in which two thiolates form bridging ligands. The entire UME6 gene has been cloned and overexpressed and binds more tightly to the URSl sequence than the zinc binuclear cluster domain alone. DNase 1 footprints of UME6 on URS1-containing DNA show that the protein protects the phosphodiesters of the 5'-CCGCCG-3' region within the URSl sequence.

show abstract

“…The "'Cd NMR spectrum gives a single peak at 745 pprn , indicating the Cd is bound to four sulfurs (Armitage & Otvos, 1982;Summers, 1988;Coleman, 1993;Henehan et al, 1993). A single peak at 723 ppm was observed for the "'Cd form of Rd, the difference in chemical shift suggesting a slightly different geometry at the metal center for the two proteins.…”

mentioning

confidence: 98%

NMR determination of the global structure of the ¹¹³Cd derivative of desulforedoxin: Investigation of the hydrogen bonding pattern at the metal center

Goodfellow¹,

Rusnak²,

Moura³

et al. 1998

Protein Science

View full text Add to dashboard Cite

Desulforedoxin (Dx) is a simple homodimeric protein isolated from Desulfovibrio gigas (Dg) containing a distorted rubredoxin‐like center with one iron coordinated by four cysteinyl residues (7.9 kDa with 36 amino acids per monomer). In order to probe the geometry and the H‐bonding at the active site of Dx, the protein was reconstituted with 113Cd and the solution structure determined using 2D NMR methods. The structure of this derivative was initially compared with the NMR solution structure of the Zn form (Goodfellow BJ et al., 1996, J Biol Inorg Chem 1:341‐353). Backbone amide protons for G4, D5, G13, L11 NH, and the Q14 NH side‐chain protons, H‐bonded in the X‐ray structure, were readily exchanged with solvent. Chemical shift differences observed for amide protons near the metal center confirm the H‐bonding pattern seen in the X‐ray model (Archer M et al., 1995, J Mol Biol 251:690‐702) and also suggest that H‐bond lengths may vary between the Fe, Zn, and 113Cd forms. The H‐bonding pattern was further probed using a heteronuclear spin echo difference (HSED) experiment; the results confirm the presence of NH‐S H‐bonds inferred from D2O exchange data and observed in the NMR family of structures. The presence of “H‐bond mediated” coupling in Dx indicates that the NH‐S H‐bonds at the metal center have significant covalent character. The HSED experiment also identified an intermonomer “through space” coupling for one of the L26 methyl groups, indicating its proximity to the 113Cd center in the opposing monomer. This is the first example of an intermonomer “through space” coupling. Initial structure calculations produced subsets of NMR families with the S of C28 pointing away from or toward the L26 methyl: only the subset with the C28 sulfur pointing toward the L26 methyl could result in a “through space” coupling. The HSED result was therefore included in the structure calculations. Comparison of the Fe, Zn, and 113Cd forms of Dx suggests that the geometry of the metal center and the global fold of the protein does not vary to any great extent, although the H‐bond network varies slightly when Cd is introduced. The similarity between the H‐bonding pattern seen at the metal center in Dx, Rd (including H‐bonded and through space‐mediated coupling), and many zinc‐finger proteins suggests that these H‐bonds are structurally vital for stabilization of the metal centers in these proteins.

show abstract

[2] Cadmium-113 nuclear magnetic resonance applied to metalloproteins

Cited by 65 publications

References 35 publications

Isolation and characterisation of metallothionein from the clam Ruditapes decussatus

Isolation and characterisation of metallothionein from the clam Ruditapes decussatus

UME6, a negative regulator of meiosis insaccharomyces cerevisiae, contains a C-terminal Zn₂Cys₆binuclear cluster that binds the URS1 DNA sequence in a zinc-dependent manner

NMR determination of the global structure of the ¹¹³Cd derivative of desulforedoxin: Investigation of the hydrogen bonding pattern at the metal center

Contact Info

Product

Resources

About

[2] Cadmium-113 nuclear magnetic resonance applied to metalloproteins

Cited by 65 publications

References 35 publications

Isolation and characterisation of metallothionein from the clam Ruditapes decussatus

Isolation and characterisation of metallothionein from the clam Ruditapes decussatus

UME6, a negative regulator of meiosis insaccharomyces cerevisiae, contains a C-terminal Zn2Cys6binuclear cluster that binds the URS1 DNA sequence in a zinc-dependent manner

NMR determination of the global structure of the 113Cd derivative of desulforedoxin: Investigation of the hydrogen bonding pattern at the metal center

Contact Info

Product

Resources

About

UME6, a negative regulator of meiosis insaccharomyces cerevisiae, contains a C-terminal Zn₂Cys₆binuclear cluster that binds the URS1 DNA sequence in a zinc-dependent manner

NMR determination of the global structure of the ¹¹³Cd derivative of desulforedoxin: Investigation of the hydrogen bonding pattern at the metal center