title: Conformation of equine pituitary somatotropin.
abstract: Equine pituitary somatotropin (growth hormone) has been studied by zero-order and second-order absorption spectroscopy, and by circular dichroism. Difference absorption spectra have also been generated during proteolytic digestion of the hormone. The molar extinction coefficient of the native protein was found to be 16,050 +/- 330 M-1 cm-1 at 278.1 nm. Comparison of the conformations of equine somatotropin and somatotropins isolated from several other mammalian species indicates a close structural relationship between these molecules. With the increasing number of species which have been studied, it is becoming evident that with regard to conformation, the somatotropins can be subdivided into at least three major groups.
mesh_terms: D000818:Animals; D002942:Circular Dichroism; D013006:Growth Hormone; D006736:Horses; D010446:Peptide Fragments; D011487:Protein Conformation; D013056:Spectrophotometry, Ultraviolet; D013820:Thermolysin; D014357:Trypsin
chemical_list: D010446:Peptide Fragments; D013006:Growth Hormone; D014357:Trypsin; D013820:Thermolysin