Related ArticlesMetal ion binding to calmodulin: NMR and fluorescence studies.
Biometals. 1998 Sep;11(3):213-22
Authors: Ouyang H, Vogel HJ
Calmodulin is an important second messenger protein which is involved in a large variety of cellular pathways. Calmodulin is sensitive to fluctuations in the intracellular Ca2+ levels and is activated by the binding of four Ca2+ ions. In spite of the important role it plays in signal transduction pathways, it shows a surprisingly broad specificity for binding metal ions. Using 15N-Gly biosynthetically-labelled calmodulin, we have studied the binding of different metal ions to calmodulin, including K+, Na+, Ca2+, Mg2+, Zn2+, Cd2+, Pb2+, Hg2+, Sr2+, La3+ and Lu3+, by 1H,15N HMQC NMR experiments. The effects of these ions on the substrate-binding ability of calmodulin have also been studied by fluorescence spectroscopy of the single tryptophan residue in a 22-residue synthetic peptide encompassing the skeletal muscle myosin light chain kinase calmodulin-binding domain. Most of these metal ions can activate a calmodulin target enzyme to some extent, though they bind to calmodulin in a different manner. Mg2+, which is of direct physiological interest, has a distinct site-preference for calmodulin, as it shows the highest affinity for site I in the N-terminal domain, while the C-terminal sites III and IV are the high affinity binding sites for Ca2+ (as well as for Cd2+). At a high concentration of Mg2+ and a low concentration of Ca2+, calmodulin can bind Mg2+ in its N-terminal lobe while the C-terminal domain is occupied by Ca2+; this species could exist in resting cells in which the Mg2+ level significantly exceeds that of Ca2+. Moreover, our data suggest that the toxicity of Pb(2+)--which, like Sr2+, binds with an equal and high affinity to all four sites--may be related to its capacity to tightly bind and improperly activate calmodulin.
NMR, biophysical and biochemical studies reveal the minimal calmodulin-binding domain of the HIV-1 matrix protein.
NMR, biophysical and biochemical studies reveal the minimal calmodulin-binding domain of the HIV-1 matrix protein.
NMR, biophysical and biochemical studies reveal the minimal calmodulin-binding domain of the HIV-1 matrix protein.
J Biol Chem. 2011 Jul 28;
Authors: Samal AB, Ghanam RH, Fernandez TF, Monroe EB, Saad JS
Subcellular distribution of Calmodulin (CaM) in human immunodeficiency virus type-1 (HIV-1) infected cells is distinct from that observed in uninfected cells. CaM has been shown to interact and co-localize with the HIV-1 Gag protein...
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[NMR paper] Effect of urea denaturation on tryptophan fluorescence and nucleotide binding on tubu
Effect of urea denaturation on tryptophan fluorescence and nucleotide binding on tubulin studied by fluorescence and NMR spectroscopic methods.
Related Articles Effect of urea denaturation on tryptophan fluorescence and nucleotide binding on tubulin studied by fluorescence and NMR spectroscopic methods.
Physiol Chem Phys Med NMR. 2001;33(2):139-51
Authors: Kuchroo K, Maity H, Kasturi SR
Tubulin, the major protein of microtubules, has been shown to be an example of protein undergoing multistep unfolding. Local unfolding and stepwise loss of a...
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[NMR paper] NMR studies of metal ion binding to the Zn-finger-like HNH motif of colicin E9.
NMR studies of metal ion binding to the Zn-finger-like HNH motif of colicin E9.
Related Articles NMR studies of metal ion binding to the Zn-finger-like HNH motif of colicin E9.
J Inorg Biochem. 2000 Apr;79(1-4):365-70
Authors: Hannan JP, Whittaker SB, Hemmings AM, James R, Kleanthous C, Moore GR
The 134 amino acid DNase domain of colicin E9 contains a zinc-finger-like HNH motif that binds divalent transition metal ions. We have used 1D 1H and 2D 1H-15N NMR methods to characterise the binding of Co2+, Ni2+ and Zn2+ to this protein. Data for the...
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[NMR paper] [13C]Methionine NMR and metal-binding studies of recombinant human transferrin N-lobe
Methionine NMR and metal-binding studies of recombinant human transferrin N-lobe and five methionine mutants: conformational changes and increased sensitivity to chloride.
Related Articles Methionine NMR and metal-binding studies of recombinant human transferrin N-lobe and five methionine mutants: conformational changes and increased sensitivity to chloride.
Biochem J. 1999 Dec 15;344 Pt 3:881-7
Authors: He QY, Mason AB, Tam BM, MacGillivray RT, Woodworth RC
The N-lobe of human serum transferrin (hTF/2N) and single point mutants in which each...
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[NMR paper] 1H NMR and fluorescence studies of the complexation of DMPG by wheat non-specific lip
1H NMR and fluorescence studies of the complexation of DMPG by wheat non-specific lipid transfer protein. Global fold of the complex.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles 1H NMR and fluorescence studies of the complexation of DMPG by wheat non-specific lipid transfer protein. Global fold of the complex.
FEBS Lett. 1997 Oct 20;416(2):130-4
Authors: Sodano P, Caille A, Sy D, de Person G, Marion D, Ptak M
Plant non-specific lipid transfer proteins (LTPs) are...
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[NMR paper] NMR and stopped-flow studies of metal ion binding to alpha-lactalbumins.
NMR and stopped-flow studies of metal ion binding to alpha-lactalbumins.
Related Articles NMR and stopped-flow studies of metal ion binding to alpha-lactalbumins.
Biochim Biophys Acta. 1996 Mar 7;1293(1):72-82
Authors: Aramini JM, Hiraoki T, Grace MR, Swaddle TW, Chiancone E, Vogel HJ
1H-NMR spectroscopy and stopped-flow techniques have been used to investigate the binding of a host of metal ions to alpha-lactalbumins from bovine, goat, and human sources. We have identified two 1H-NMR markers diagnostic of metal ion binding to the...
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[NMR paper] Site-directed mutagenesis, fluorescence, and two-dimensional NMR studies on microenvi
Site-directed mutagenesis, fluorescence, and two-dimensional NMR studies on microenvironments of effector region aromatic residues of human c-Ha-Ras protein.
Related Articles Site-directed mutagenesis, fluorescence, and two-dimensional NMR studies on microenvironments of effector region aromatic residues of human c-Ha-Ras protein.
Biochemistry. 1994 Jan 11;33(1):65-73
Authors: Yamasaki K, Shirouzu M, Muto Y, Fujita-Yoshigaki J, Koide H, Ito Y, Kawai G, Hattori S, Yokoyama S, Nishimura S
The Tyr residues in positions 32 and 40 of human c-Ha-Ras...
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[NMR paper] Site-directed mutagenesis, fluorescence, and two-dimensional NMR studies on microenvi
Site-directed mutagenesis, fluorescence, and two-dimensional NMR studies on microenvironments of effector region aromatic residues of human c-Ha-Ras protein.
Related Articles Site-directed mutagenesis, fluorescence, and two-dimensional NMR studies on microenvironments of effector region aromatic residues of human c-Ha-Ras protein.
Biochemistry. 1994 Jan 11;33(1):65-73
Authors: Yamasaki K, Shirouzu M, Muto Y, Fujita-Yoshigaki J, Koide H, Ito Y, Kawai G, Hattori S, Yokoyama S, Nishimura S
The Tyr residues in positions 32 and 40 of human c-Ha-Ras...