The disulfide bond pairing of the pheromones Er-1 and Er-2 of the ciliated protozoan Euplotes raikovi.
The disulfide pairings of the two Euplotes raikovi pheromones Er-1 and Er-2 have been determined by chemical and mass spectrometric analyses. Cystine-linked peptides from thermolytic digestions of the native molecules were purified by reverse-phase high performance liquid chromatography and identified in the known sequences to make the assignments. The same pairing, Cys(I)-Cys(IV), Cys(II)-Cys(VI), and Cys(III)-Cys(V), was found in both pheromones, suggesting that this pattern occurs commonly throughout this family of molecules. This arrangement of disulfides indicates that the three-dimensional structure is defined by three loops, which can vary in size and charge distribution from one pheromone to another.
Stewart
A E
AE
Department of Biological Chemistry, College of Medicine, University of California, Irvine 92717.
Raffioni
S
S
Chaudhary
T
T
Chait
B T
BT
Luporini
P
P
Bradshaw
R A
RA
D000595:Amino Acid Sequence; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003553:Cystine; D004220:Disulfides / Q000032:analysis; D016812:Euplotes / Q000502:physiology*; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000737:chemistry*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000302:isolation & purification; D010675:Pheromones / Q000737:chemistry*; D011487:Protein Conformation; D015800:Protozoan Proteins / Q000737:chemistry*
D004220:Disulfides; D008565:Membrane Proteins; D010446:Peptide Fragments; D010675:Pheromones; D015800:Protozoan Proteins; C081617:mating pheromone 2, Euplotes raikovi; C057783:mating pheromone Er-1, Euplotes raikovi; D003553:Cystine