Biomaterial Database

Amino acid sequences of the two polypeptide chains in beta1-bungarotoxin from the venom of Bungarus multicinctus. 1978

K Kondo, and K Narita, and C Y Lee

The two dissimilar composite polypeptide chains (A and B) in beta1-bungarotoxin were isolated as their reduced and carboxymethylated derivatives as reported in the preceding paper. The N-terminal sequences were determined with a sequenator up to the 39th residue for the RCM-A chain and up to the 25th residue for the RCM-B chain with repetitive yields of 90-95%. The tryptic and chymotryptic peptides from the two chains were isolated and their structures were determined by manual Edman degradation together with dansyl-Edman and carboxypeptidases A and Y. To complete the primary structures of the two chains, information on the tryptic peptides derived from the maleylated derivatives of the two chains was also used. The completed amino acid sequence of the A chain containing 120 residues (molecular weight, 13,500) is similar to that of notexin, a presynaptic neurotoxin from Australian tiger snake venom, and phospholipases A from other snake venoms. The amino acid sequence of the 60 residues in the B chain (molecular weight, 7,000) bears no resemblance to any basic polypeptides from snake venoms. The B chain probably plays a significant role by interacting with some components in presynaptic membranes of neurosmuscular junctions.

UI	MeSH Term	Description	Entries
D008722	Methods	A series of steps taken in order to conduct research.	Techniques,Methodological Studies,Methodological Study,Procedures,Studies, Methodological,Study, Methodological,Method,Procedure,Technique
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D002038	Bungarotoxins	Neurotoxic proteins from the venom of the banded or Formosan krait (Bungarus multicinctus, an elapid snake). alpha-Bungarotoxin blocks nicotinic acetylcholine receptors and has been used to isolate and study them; beta- and gamma-bungarotoxins act presynaptically causing acetylcholine release and depletion. Both alpha and beta forms have been characterized, the alpha being similar to the large, long or Type II neurotoxins from other elapid venoms.	alpha-Bungarotoxin,beta-Bungarotoxin,kappa-Bungarotoxin,alpha Bungarotoxin,beta Bungarotoxin,kappa Bungarotoxin
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
D000596	Amino Acids	Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.	Amino Acid,Acid, Amino,Acids, Amino
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