Related ArticlesDisulfide bonds in homo- and heterodimers of EF-hand subdomains of calbindin D9k: stability, calcium binding, and NMR studies.
Protein Sci. 1993 Jun;2(6):985-1000
Authors: Linse S, Thulin E, Sellers P
The effect of decreased protein flexibility on the stability and calcium binding properties of calbindin D9k has been addressed in studies of a disulfide bridged calbindin D9k mutant, denoted (L39C + P43M + I73C), with substitutions Leu 39-->Cys, Ile 73-->Cys, and Pro 43-->Met. Backbone 1H NMR assignments show that the disulfide bond, which forms spontaneously under air oxidation, is well accommodated. The disulfide is inserted on the opposite end of the protein molecule with respect to the calcium sites, to avoid direct interference with these sites, as confirmed by 113Cd NMR. The effect of the disulfide bond on calcium binding was assessed by titrations in the presence of a chromophoric chelator. A small but significant effect on the cooperativity was found, as well as a very modest reduction in calcium affinity. The disulfide bond increases Tm, the transition midpoint of thermal denaturation, of calcium free calbindin D9k from 85 to 95 degrees C and Cm, the urea concentration of half denaturation, from 5.3 to 8.0 M. Calbindins with one covalent bond linking the two EF-hand subdomains are equally stable regardless if the covalent link is the 43-44 peptide bond or the disulfide bond. Kinetic remixing experiments show that separated CNBr fragments of (L39C + P43M + I73C), each comprising one EF-hand, form disulfide linked homodimers. Each homodimer binds two calcium ions with positive co-operativity, and an average affinity of 10(6) M-1. Disulfide linkage dramatically increases the stability of each homodimer. For the homodimer of the C-terminal fragment Tm increases from 59 +/- 2 without covalent linkage to 91 +/- 2 degrees C with disulfide, and Cm from approximately 1.5 to 7.5 M. The overall topology of this homodimer is derived from 1H NMR assignments and a few key NOEs.
Conformational analysis by quantitative NOE measurements of the β-proton pairs across individual disulfide bonds in proteins
Conformational analysis by quantitative NOE measurements of the β-proton pairs across individual disulfide bonds in proteins
Abstract NOEs between the β-protons of cysteine residues across disulfide bonds in proteins provide direct information on the connectivities and conformations of these important cross-links, which are otherwise difficult to investigate. With conventional -proteins, however, fast spin diffusion processes mediated by strong dipolar interactions between geminal β-protons prohibit the quantitative measurements and thus the analyses of long-range NOEs across...
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NMR Structural Inference of Symmetric Homo-Oligomers.
NMR Structural Inference of Symmetric Homo-Oligomers.
NMR Structural Inference of Symmetric Homo-Oligomers.
J Comput Biol. 2011 Jun 30;
Authors: Chandola H, Yan AK, Potluri S, Donald BR, Bailey-Kellogg C
Abstract Symmetric homo-oligomers represent a majority of proteins, and determining their structures helps elucidate important biological processes, including ion transport, signal transduction, and transcriptional regulation. In order to account for the noise and sparsity in the distance restraints used in Nuclear Magnetic Resonance (NMR)...
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(1)H, (13)C and (15)N NMR assignments of the C1A and C1B subdomains of PKC-delta.
(1)H, (13)C and (15)N NMR assignments of the C1A and C1B subdomains of PKC-delta.
Related Articles (1)H, (13)C and (15)N NMR assignments of the C1A and C1B subdomains of PKC-delta.
Biomol NMR Assign. 2010 Dec 4;
Authors: Brian PZ, Jamie CB, David JN
The Protein Kinase C family of enzymes is a group of serine/threonine kinases that play central roles in cell-cycle regulation, development and cancer. A key step in the activation of PKC is translocation to membranes and binding of membrane-associated activators including diacylglycerol (DAG)....
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[NMR paper] NMR solution structure of calerythrin, an EF-hand calcium-binding protein from Saccha
NMR solution structure of calerythrin, an EF-hand calcium-binding protein from Saccharopolyspora erythraea.
Related Articles NMR solution structure of calerythrin, an EF-hand calcium-binding protein from Saccharopolyspora erythraea.
Eur J Biochem. 2003 Jun;270(11):2505-12
Authors: Tossavainen H, Permi P, Annila A, Kilpeläinen I, Drakenberg T
The structure of calerythrin, a prokaryotic 20 kDa calcium-binding protein has been determined by solution NMR spectroscopy. Distance, dihedral angle, J coupling, secondary chemical shift, residual dipolar...
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[NMR paper] NMR derived solution structure of an EF-hand calcium-binding protein from Entamoeba H
NMR derived solution structure of an EF-hand calcium-binding protein from Entamoeba Histolytica.
Related Articles NMR derived solution structure of an EF-hand calcium-binding protein from Entamoeba Histolytica.
Biochemistry. 2001 Dec 4;40(48):14392-403
Authors: Atreya HS, Sahu SC, Bhattacharya A, Chary KV, Govil G
We present the three-dimensional (3D) solution structure of a calcium-binding protein from Entamoeba histolytica (EhCaBP), an etiologic agent of amoebiasis affecting millions worldwide. EhCaBP is a 14.7 kDa (134 residues) monomeric...
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[NMR paper] Two structural subdomains of barstar detected by rapid mixing NMR measurement of amid
Two structural subdomains of barstar detected by rapid mixing NMR measurement of amide hydrogen exchange.
Related Articles Two structural subdomains of barstar detected by rapid mixing NMR measurement of amide hydrogen exchange.
Proteins. 1998 Feb 15;30(3):295-308
Authors: Bhuyan AK, Udgaonkar JB
Equilibrium amide hydrogen exchange studies of barstar have been carried out at pH 6.7, 32 degrees C using one- and two-dimensional nuclear magnetic resonance. An unusually large fraction of the backbone amide hydrogens of barstar exchange too fast to...
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[NMR paper] High resolution NMR solution structure of the leucine zipper domain of the c-Jun homo
High resolution NMR solution structure of the leucine zipper domain of the c-Jun homodimer.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--highwire.stanford.edu-icons-externalservices-pubmed-standard-jbc_full_free.gif Related Articles High resolution NMR solution structure of the leucine zipper domain of the c-Jun homodimer.
J Biol Chem. 1996 Jun 7;271(23):13663-7
Authors: Junius FK, O'Donoghue SI, Nilges M, Weiss AS, King GF
The solution structure of the c-Jun leucine zipper domain has been determined to high resolution using a new...
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[NMR paper] Reductive cleavage and regeneration of the disulfide bonds in Streptomyces subtilisin
Reductive cleavage and regeneration of the disulfide bonds in Streptomyces subtilisin inhibitor (SSI) as studied by the carbonyl 13C NMR resonances of cysteinyl residues.
Related Articles Reductive cleavage and regeneration of the disulfide bonds in Streptomyces subtilisin inhibitor (SSI) as studied by the carbonyl 13C NMR resonances of cysteinyl residues.
J Biomol NMR. 1991 May;1(1):49-64
Authors: Uchida K, Miyake Y, Kainosho M
Four enhanced carbonyl carbon resonances were observed when Streptomyces subtilisin inhibitor (SSI) was labeled by...
Disulfide bonds in homo- and heterodimers of EF-hand subdomains of calbindin D9k: sta
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