title: Purification, crystallisation and preliminary X-ray studies on avian pancreatic polypeptide.
abstract: A pancreatic polypeptide with some hormonal properties has been purified from chicken and turkey pancreas using acid-ethanol extraction, gel filtration and anion-exchange chromatography. The material has been crystallised. The crystals are monoclinic with space group C2. Preliminary isomorphous replacement experiments have so far provided a single-site derivative with Hg(NO3)2. A low-resolution electron density map phased with this derivative using anomalous scattering considered together with Patterson function calculations suggest that the molecules are partly helical and are arranged as a compact dimer about the crystallographic two-fold axis. The structure and association of these molecules are compared with those of insulin and glucagon, pancreatic protein and polypeptide hormones respectively, which have been studied in great detail.
mesh_terms: D000818:Animals; D002417:Cattle; D002645:Chickens; D008628:Mercury; D010187:Pancreatic Hormones / Q000302:isolation & purification*; D010455:Peptides / Q000302:isolation & purification*; D011487:Protein Conformation; D013045:Species Specificity; D014422:Turkeys; D014961:X-Ray Diffraction
chemical_list: D010187:Pancreatic Hormones; D010455:Peptides; D008628:Mercury