103840-07-9Relevant academic research and scientific papers
NosA catalyzing carboxyl-terminal amide formation in nosiheptide maturation via an enamine dealkylation on the serine-extended precursor peptide
Yu, Yi,Guo, Heng,Zhang, Qi,Duan, Lian,Ding, Ying,Liao, Rijing,Lei, Chun,Shen, Ben,Liu, Wen
, p. 16324 - 16326 (2010)
The carboxyl-terminal amide group has been often found in many bioactive peptide natural products, including nosiheptide belonging to the over 80 entity-containing thiopeptide family. Upon functional characterization of a novel protein NosA in nosiheptide biosynthesis, herein we report an unusual C-terminal amide forming strategy in general for maturating certain amide-terminated thiopeptides by processing their precursor peptides featuring a serine extension. NosA acts on an intermediate bearing a bis-dehydroalanine tail and catalyzes an enamide dealkylation to remove the acrylate unit originating from the extended serine residue.
KINETICS OF CHOLINESTERASE INHIBITION BY ORGANOPHOSPHORUS COMPOUNDS: DETERMINATION OF DISSOCIATION AND PHOSPHORYLATION CONSTANTS IN THE PRESENCE OF LOW SUBSTRATE CONCENTRATIONS
Debord, Jean,Penicaut, Bernard,Labadie, Michel
, p. 57 - 66 (2007/10/02)
A method has been developed to determine the dissociation constant Kd and the phosphorylation constant k2 of an irreversible organophosphorus inhibitor of cholinesterase.The method consists in recording the progress curve of enzymatic hydrolysis of a substrate in the presence of the inhibitor.The use of a very low substrate concentration limits the competitive action of the substrate and renders the method more sensitive to inhibition, particularly to the binding step.The method is more general than the early method of Hart and O'Brien because it is not limited by the extent of substrate hydrolysis.The method has been used to study the anticholinesteratic activity of the anticancer drug triethylenethiophosphoramide (thio-TEPA).The results are discussed with respect to the chemical reactivity of this compound.
