title: First synthesis of a fully active spin-labeled peptide hormone.
abstract: For the first time in the electron spin resonance (ESR) and peptide synthesis fields, a fully active spin-labeled peptide hormone was reported. The ESR spectra of this alpha-melanocyte stimulating hormone (alpha-MSH) analogue (acetyl-Toac0-alpha-MSH) where Toac is the paramagnetic amino acid probe 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid, suggested a pH-independent conformation and a more restricted movement comparatively to the free Toac. Owing to its equivalent biological potency in a skin pigmentation assay as compared to the native alpha-MSH and its unique characteristic (paramagnetic, naturally fluorescent and fully active), this analogue is of great potential for investigation of relevant physiological roles reported for alpha-MSH.
authors: Departamento de Biofisica, Universidade Federal de São Paulo, SP, Brazil.
authors: S R
authors: SR
authors: Barbosa
authors: E M
authors: EM
authors: Cilli
authors: M T
authors: MT
authors: Lamy-Freund
authors: A M
authors: AM
authors: Castrucci
authors: C R
authors: CR
authors: Nakaie
mesh_terms: D004578:Electron Spin Resonance Spectroscopy; D011487:Protein Conformation; D013113:Spin Labels; D000521:alpha-MSH / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D013113:Spin Labels; D000521:alpha-MSH