title: Computer modelling studies of ribonuclease A-pyrimidine nucleotide complexes.
abstract: Different modes of binding of pyrimidine monophosphates 2'-UMP, 3'-UMP, 2'-CMP and 3'-CMP to ribonuclease (RNase) A are studied by energy minimization in torsion angle and subsequently in Cartesian coordinate space. The results are analysed in the light of primary binding sites. The hydrogen bonding pattern brings out roles for amino acids such as Asn44 and Ser123 apart from the well known active site residues viz., His12,Lys41,Thr45 and His119. Amino acid segments 43-45 and 119-121 seem to be guiding the ligand binding by forming a pocket. Many of the active site charged residues display considerable movement upon nucleotide binding.
authors.affiliation: Molecular Biophysics Unit, Indian Institute of Science, Bangalore.
authors.forename: K
authors.initials: K
authors.lastname: Seshadri
authors.forename: P V
authors.initials: PV
authors.lastname: Balaji
authors.forename: V S
authors.initials: VS
authors.lastname: Rao
authors.forename: S
authors.initials: S
authors.lastname: Vishveshwara
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D003198:Computer Simulation; D003568:Cytidine Monophosphate / Q000737:chemistry / Q000378:metabolism*; D006860:Hydrogen Bonding; D008958:Models, Molecular; D011487:Protein Conformation; D012259:Ribonuclease, Pancreatic / Q000737:chemistry / Q000378:metabolism*; D014542:Uridine Monophosphate / Q000737:chemistry / Q000378:metabolism*
chemical_list: D014542:Uridine Monophosphate; D012259:Ribonuclease, Pancreatic; D003568:Cytidine Monophosphate