title: Fluorescence study of neurohypophyseal hormones and their analogues. Distance distributions in a series of arginine-vasopressin analogues.
abstract: Analogues of arginine-vasopressin (AVP) in which substitution of the proline residue in position 7 (by either sarcosine or N-methylalanine) combined with replacement of the cysteine residue in position 1 were the subject of a fluorescence and molecular mechanics study. We obtained two groups of analogues: selective antidiuretic agonists (cysteine or beta-mercaptopropionic acid in position 1) and pressor and uterotonic antagonists (deaminopenicillamine or beta-mercapto-beta, beta-cyclopentamethylenepropionic acid in position 1). Using frequency-domain measurements of fluorescence resonance energy transfer (FRET) we estimated the distance distribution between the phenolic ring of Tyr2 and the disulphide bridge Cys1-Cys6. We also analyzed acrylamide quenching of tyrosyl fluorescence to determine the exposure of the tyrosyl ring to the solvent. Results from fluorescence experiments were compared with those from Monte Carlo simulation (ECEPP/3 force-field).
authors.affiliation: Faculty of Chemistry, University of Gdańsk, Poland.
authors.forename: W
authors.initials: W
authors.lastname: Wiczk
authors.forename: L
authors.initials: L
authors.lastname: Lankiewicz
authors.forename: F
authors.initials: F
authors.lastname: Kasprzykowski
authors.forename: S
authors.initials: S
authors.lastname: Ołdziej
authors.forename: H
authors.initials: H
authors.lastname: Szmaciński
authors.forename: J R
authors.initials: JR
authors.lastname: Lakowicz
authors.forename: Z
authors.initials: Z
authors.lastname: Grzonka
mesh_terms: D001127:Arginine Vasopressin / Q000031:analogs & derivatives* / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003198:Computer Simulation; D004220:Disulfides / Q000737:chemistry; D004735:Energy Transfer; D009010:Monte Carlo Method; D010904:Pituitary Gland, Posterior / Q000737:chemistry*; D010907:Pituitary Hormones / Q000737:chemistry*; D011487:Protein Conformation; D013050:Spectrometry, Fluorescence
chemical_list: D004220:Disulfides; D010907:Pituitary Hormones; D001127:Arginine Vasopressin