0000000000825452
AUTHOR
Marcin Drag
Unnatural amino acids increase activity and specificity of synthetic substrates for human and malarial cathepsin C
Mammalian cathepsin C is primarily responsible for the removal of N-terminal dipeptides and activation of several serine proteases in inflammatory or immune cells, while its malarial parasite ortholog dipeptidyl aminopeptidase 1 plays a crucial role in catabolizing the hemoglobin of its host erythrocyte. In this report, we describe the systematic substrate specificity analysis of three cathepsin C orthologs from Homo sapiens (human), Bos taurus (bovine) and Plasmodium falciparum (malaria parasite). Here, we present a new approach with a tailored fluorogenic substrate library designed and synthesized to probe the S1 and S2 pocket preferences of these enzymes with both natural and a broad ran…
α-Aminoalkylphosphonates as a tool in experimental optimisation of P1 side chain shape of potential inhibitors in S1 pocket of leucine- and neutral aminopeptidases
Abstract The synthesis and biological activity studies of the series of structurally different α-aminoalkylphosphonates were performed in order to optimise the shape of the side chain of the potential inhibitors in S1 pocket of leucine aminopeptidase [E.C.3.4.11.1]. Analysis of a series of compounds with aromatic, aliphatic and alicyclic P1 side chains enabled to find out the structural features, optimal for that fragment of inhibitors of LAP. The most active among all investigated compounds were the phosphonic analogues of homo-tyrosine ( K i = 120 nM) and homo-phenylalanine ( K i = 140 nM), which even as racemic mixtures were better inhibitors in comparison with the best till now-phosph…
Substrate specificity screening of oat (Avena sativa) seeds aminopeptidase demonstrate unusually broad tolerance in S1 pocket.
Aminopeptidases are proteolytic enzymes that remove one amino acid at a time from N-terminus of peptidic substrates. In plants, inhibitors of aminopeptidases can find potential applications in agriculture as herbicides. In this report we have used a library of fluorogenic derivatives of natural and unnatural amino acids for substrate specificity profiling of oat (Avena sativa) aminopeptidase. Interestingly, we have found that this enzyme recognizes effectively among the natural amino acids basic residues like Arg and Lys, hydrophobic Phe, Leu and Met, but also to some extent acidic residues Asp and Glu. In the case of unnatural amino acids hydrophobic residues (hPhe and hCha) and basic hArg…
Stereoselective synthesis of 1-aminoalkanephosphonic acids with two chiral centers and their activity towards leucine aminopeptidase
The stereoselective synthesis of 1-amino-2-alkylalkanephosphonic acids, namely, compounds bearing two chiral centers, was achieved by the condensation of hypophosphorous acid salts of (R)(+) or (S)(-)-N-alpha-methylbenzylamine with the appropriate aldehydes in isopropanol. Simultaneous deprotection and oxidation by the action of bromine water provided equimolar mixtures of the RS:RR and SR:SS diastereomers of desired acids. They appeared to act as moderate inhibitors of kidney leucine aminopeptidase with potency dependent on the absolute configuration of both centers of chirality.