Characterization of the secondary structure of calmodulin in complex with a calmodulin-binding domain peptide

Journal Article · Tue Feb 11 00:00:00 EST 1992 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00120a022· OSTI ID:5559712

Roth, S M; Schneider, D M; Strobel, L A; Wand, A J ^[1]; Van Berkum, M F.A.; Means, A R ^[2]

---

1. Inst. for Cancer Research, Philadelphia, PA (United States) Univ. of Illinois, Urbana (United States)
2. Baylor Coll., Houston, TX (United States)

The interaction between calcium-saturated chicken calmodulin and a peptide corresponding to the calmodulin-binding domain of the chicken smooth muscle myosin light chain kinase has been studied by multinuclear and multidimensional nuclear magnetic resonance methods. Extensive {sup 1}H and {sup 15}N resonance assignments of calmodulin in the complex have been obtained from the analysis of two- and three-dimensional nuclear magnetic resonance spectra. The assignment of calmodulin in the complex was facilitated by the use of selective labeling of the protein with {alpha}-{sup 15}N-labeled valine, alanine, lysine, leucine, and glycine. These provided reference points during the main-chain-directed analysis of three-dimensional spectra of complexes prepared with uniformly {sup 15}N-labeled calmodulin. The pattern of nuclear Overhauser effects (NOE) seen among main-chain amide NH, C{sub {alpha}}H, and C{sub {beta}}H hydrogens indicates that the secondary structure of the globular domains of calmodulin in the complex closely corresponds to that observed in the calcium-saturated state of the protein in the absence of bound peptide. However, the backbone conformation of residues 76-84 adopts an extended chain conformation upon binding of the peptide in contrast to its helical conformation in the absence of peptide. A sufficient number of NOEs between the globular domains of calmodulin and the bound peptide have been found to indicate that the N- and C-terminal regions of the peptide interact with the C- and N-terminal domains of calmodulin, respectively. The significance of these results are discussed in terms of recently proposed models for the structure of calmodulin-peptide complexes.

• OSTI ID: 5559712
• Journal Information: Biochemistry; (United States), Vol. 31:5; ISSN 0006-2960
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CALMODULIN
NUCLEAR MAGNETIC RESONANCE
AMMONIUM CHLORIDES
GLYCINE
LEUCINE
LYSINE
NITROGEN 15
OVERHAUSER EFFECT
PEPTIDES
AMINO ACIDS
AMMONIUM COMPOUNDS
AMMONIUM HALIDES
CARBOXYLIC ACIDS
CHLORIDES
CHLORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
NITROGEN ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PROTEINS
RESONANCE
STABLE ISOTOPES
550201* - Biochemistry- Tracer Techniques