Inhibitor profiling of the Pseudomonas aeruginosa virulence factor LasB using N-alpha mercaptoamide template-based inhibitors.
We report on the synthesis and biological evaluation of a focussed library of N-alpha mercaptoamide containing dipeptides as inhibitors of the zinc metallopeptidase Pseudomonas aeruginosa elastase (LasB, EC 3.4.24.26). The aim of the study was to derive an inhibitor profile for LasB with regard to mapping the S'1 binding site of the enzyme. Consequently, a focussed library of 160 members has been synthesised, using standard Fmoc-solid phase methods (on a Rink-amide resin), in which a subset of amino acids including examples of those with basic (Lys, Arg), aromatic (Phe, Trp), large aliphatic (Val, Leu) and acidic (Asp, Glu) side-chains populated the P'2 position of the inhibitor sequence and all 20 natural amino acids were incorporated, in turn, at the P'1 position. The study has revealed a preference for aromatic and/or large aliphatic amino acids at P'1 and a distinct bias against acidic residues at P'2. Ten inhibitor sequences were discovered that exhibited sub to low micromolar Ki values.
School of Pharmacy, Queen's University of Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK.
George R
GR
Cathcart
Brendan F
BF
Gilmore
Brett
B
Greer
Pat
P
Harriott
Brian
B
Walker
D000577:Amides / Q000737:chemistry*; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D001665:Binding Sites; D020134:Catalytic Domain; D004151:Dipeptides / Q000737:chemistry* / Q000494:pharmacology; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011480:Protease Inhibitors / Q000737:chemistry* / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D013438:Sulfhydryl Compounds / Q000737:chemistry*
D000577:Amides; D001426:Bacterial Proteins; D004151:Dipeptides; D011480:Protease Inhibitors; D013438:Sulfhydryl Compounds; D008666:Metalloendopeptidases; C043859:pseudolysin, Pseudomonas aeruginosa