Two- and three-dimensional sup 1 H NMR studies of a wheat phospholipid transfer protein: Sequential resonance assignments and secondary structure

Journal Article · Tue Dec 10 00:00:00 EST 1991 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00113a016· OSTI ID:5487356

Simorre, J P; Caille, A ^[1]; Marion, D ^[2]; Marion, D ^[3]; Ptak, M ^[4]

---

1. Centre National de la Recherche Scientifique, Orleans (France)
2. Laboratoire de Resonance Magnetique en Biologie et Medecine, Grenoble (France)
3. INRA, Nantes (France)
4. Centre National de la Recherche Scientifique, Orleans (France) Univ. d'Orleans (France)

Two- and three-dimensional {sup 1}H NMR experiments have been used to sequentially assign nearly all proton resonances of the 90 residues of wheat phospholipid transfer protein. Only a few side-chain protons were not identified because of degeneracy or overlapping. The identification of spin systems and the sequential assignment were made at the same time by combining the data of the two- and three-dimensional experiments. The classical two-dimensional COSY, HOHAHA, and NOESY experiments benefit from both good resolution and high sensitivity, allowing the detection of long-range dipolar connectivities. The three-dimensional HOHAHA-NOESY experiment offers the advantage of a faster and unambiguous assignment. As a matter of fact, homonuclear three-dimensional NMR spectroscopy prove to be a very efficient method for resonance assignments of protein {sup 1}H NMR spectra which cannot be unraveled by 2D methods. An assignment strategy which overcomes most of the ambiguities has been proposed, in which each individual assignment toward the C-terminal end is supported by another in the opposite direction originating from a completely different part of the spectrum. Location of secondary structures of the phospholipid transfer protein was determined by using the method of analysis introduced here and was confirmed by {sup 3}J{sub {alpha}NH} coupling and NH exchange rates. Except for the C-terminal part, the polypeptide chain appears to be organized mainly as helical fragments connected by disulfide bridges. Further modeling will display the overall folding of the protein and should provide a better understanding of its interactions with lipids.

• OSTI ID: 5487356
• Journal Information: Biochemistry; (United States), Vol. 30:49, Issue 49; ISSN 0006-2960
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
PHOSPHOLIPIDS
NUCLEAR MAGNETIC RESONANCE
CHEMICAL SHIFT
MOLECULAR STRUCTURE
OVERHAUSER EFFECT
PROTONS
WHEAT
BARYONS
CEREALS
ELEMENTARY PARTICLES
ESTERS
FERMIONS
GRAMINEAE
HADRONS
LILIOPSIDA
LIPIDS
MAGNETIC RESONANCE
MAGNOLIOPHYTA
NUCLEONS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PLANTS
RESONANCE
550601* - Medicine- Unsealed Radionuclides in Diagnostics