Structural and NMR investigations of the ternary adducts of twenty α-amino acids and selected dipeptides with a chiral, diaqua–ytterbium complex
作者:Rachel S. Dickins、Andrei S. Batsanov、Judith A. K. Howard、David Parker、Horst Puschmann、Stefania Salamano
DOI:10.1039/b311791j
日期:——
A detailed investigation of the nature of the binding of each of the 20 common α-aminoacids and various selected dipeptides to a chiral, diaqua–ytterbium complex in aqueous solution has been carried out. Analysis of the dipolar 1H NMR paramagnetic shifts suggests that the α-aminoacids form a common chelated structure within a nine-coordinate mono-capped square antiprismatic coordination environment
Peptide bond formation by aminolysin-A catalysis: A simple approach to enzymatic synthesis of diverse short oligopeptides and biologically active puromycins
peptide bonds to give linear homo-oligopeptides, hetero-dipeptides, and cyclicdipeptides using cost-effective substrates in a one-pot reaction. Aminolysin-A can recognize several C-terminal-modified aminoacids, including the L- and D-forms, as acyl donors as well as free amines, including aminoacids and puromycin aminonucleoside, as acyl acceptors. The absence of aminoacid esters prevents the formation
Met-Ala Met-Ser Met-Val and Met-Leu. The reaction follows the overall second-order kinetics, first order each in the oxidant and the substrate. Based on the substituent and solvent effects, an outer-sphere electrontransfer from the sulfur center of the peptide to Ru(III) has been proposed as the rate controlling step of the reaction. The ET nature of the reaction is confirmed from the recorded transient
Peptide sequencing: The utility of chemical ionization mass spectrometry
作者:M. Mudgett、D. V. Bowen、F. H. Field、T. J. Kindt
DOI:10.1002/bms.1200040308
日期:1977.6
Chemicalionizationmassspectrometry is used at low resolution to determine the sequences of permethylated acetyl peptides. The method has been tested with 45 peptides, between 2 and 5 residues long, including examples of all of the common amino acids except cysteine and N-terminal asparagine. The isobutane chemicalionizationspectra contain three principal types of N-terminal sequence ion and one