Biomaterial Database

Folding of the twisted beta-sheet in bovine pancreatic trypsin inhibitor. 1985

K C Chou, and G Némethy, and M S Pottle, and H A Scheraga

The dominant role of local interactions has been demonstrated for the formation of the strongly twisted antiparallel beta-sheet structure consisting of residues 18-35 in bovine pancreatic trypsin inhibitor. Conformational energy minimization has indicated that this beta-sheet has a strong twist even in the absence of the rest of the protein molecule. The twist is maintained essentially unchanged when energy minimization is carried out by starting from the native conformation. By starting from a nontwisted beta-sheet conformation of residues 18-35, a strongly twisted structure (higher in energy than the native) is obtained. The high twist of the native-like beta-sheet is a consequence of its amino acid sequence, but it is enhanced strongly by interchain interactions that operate within the beta-sheet. The existence of the twisted beta-sheet structure does not require the presence of a disulfide bond between residue 14 and residue 38. It actually may facilitate the formation of this bond. Therefore, it is likely that the beta-sheet structure forms during an earlier stage of folding than the formation of this disulfide bond. This study provides an example of the manner in which conformational energy calculations can be used to provide information about the probable pathway of the folding of a protein.

UI	MeSH Term	Description	Entries
D008958	Models, Molecular	Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.	Molecular Models,Model, Molecular,Molecular Model
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014359	Trypsin Inhibitor, Kazal Pancreatic	A secreted KAZAL MOTIF-containing serine peptidase inhibitor that inhibits TRYPSIN. It is a protein composed of 56 amino acid residues and is different in amino acid composition and physiological activity from the Kunitz bovine pancreatic trypsin inhibitor (APROTININ). It protects against the trypsin-mediated premature activation of ENZYME PRECURSORS in the PANCREAS. Mutations in the SPINK1 gene are associated with CHRONIC PANCREATITIS.	Acidic Pancreatic Trypsin Inhibitor,Kazal Pancreatic Trypsin Inhibitor,Pancreatic Secretory Trypsin Inhibitor, Kazal,Pancreatic Trypsin Secretory Inhibitor, Kazal,Trypsin Inhibitor, Pancreatic Secretory,Inhibitor, Tumor-Associated Trypsin,Pancreatic Secretory Trypsin Inhibitor,SPINK1,Serine Peptidase Inhibitor, Kazal-Type 1,Serine Protease Inhibitor Kazal-Type 1,Trypsin Inhibitor Kazal Pancreatic,Trypsin Inhibitor, Tumor-Associated,Tumor-Associated Trypsin Inhibitor,Serine Peptidase Inhibitor, Kazal Type 1,Serine Protease Inhibitor Kazal Type 1,Trypsin Inhibitor, Tumor Associated,Tumor Associated Trypsin Inhibitor
D014361	Trypsin Inhibitors	Serine proteinase inhibitors which inhibit trypsin. They may be endogenous or exogenous compounds.	Trypsin Inhibitor,Inhibitor, Trypsin,Inhibitors, Trypsin
D046911	Macromolecular Substances	Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.	Macromolecular Complexes,Macromolecular Compounds,Macromolecular Compounds and Complexes,Complexes, Macromolecular,Compounds, Macromolecular,Substances, Macromolecular