NMR investigation of cyclo7,10[C7,X9,C10,Nle12] analogues of the alpha-factor from Saccharomyces cerevisiae.
The cyclo7,10[Cys7,Cys10,Nle12], cyclo7,10[Cys7,D-Ala9,Cys10,Nle12], and cyclo7,10[Cys7,L-Ala9,Cys10,Nle12] analogues of the alpha-factor mating pheromone (WHWLQLKPGQPMY) of the yeast Saccharomyces cerevisiae were studied in DMSO/water (80:20) and aqueous solution by nmr spectroscopy. In addition, the cyclo7,10[Cys7,D-Val9,Cys10,Nle12]alpha-fa ctor was examined in DMSO/water. Nuclear Overhauser effect (NOE) and NH d delta/dT data indicate that the cyclo7,10[Cys7,D-Val9,Cys10,Nle12]alpha-fa ctor adopts a type II beta-turn in DMSO/water and that the cyclo7,10[Cys7,D-Ala9,Cys10,Nle12]- and cyclo7,10[Cys7,L-Ala9,Cys10,Nle12]alpha-fa ctor analogues adopt type II and type I/III beta-turns, respectively, in both DMSO/water and aqueous solutions. In aqueous solution, residues 8 and 9 of the cyclo7,10[Cys7,Nle12] alpha-factor appear to adopt at least two distinct conformations, one of these being identified as a type I/III beta-turn. In contrast, the cyclo7,10[Cys7,Cys10,Nle12] alpha-factor appears to adopt predominately a type II beta-turn in DMSO/water. Quantitative NOE measurements of the cyclo7,10[Cys7,Cys10,Nle12]-, cyclo7,10[Cys7,D-Val9,Cys10,Nle12]-, and cyclo7,10[Cys7,L-Ala9,Cys10,Nle12] alpha-factors in DMSO/water were used to derive three-dimensional structures of the cyclo7,10[Cys7,Pro8,X9,Cys10] portion of these analogues.
Gounarides
J S
JS
Department of Chemistry, Hunter College, New York, New York.
Xue
C B
CB
Becker
J M
JM
Naider
F
F
D000595:Amino Acid Sequence; D005656:Fungal Proteins / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D000072235:Mating Factor; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D010456:Peptides, Cyclic / Q000737:chemistry; D010675:Pheromones / Q000737:chemistry; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D012441:Saccharomyces cerevisiae; D012996:Solutions
D005656:Fungal Proteins; D010455:Peptides; D010456:Peptides, Cyclic; D010675:Pheromones; D012996:Solutions; D000072235:Mating Factor