Foot and mouth disease leader protease (Lb(pro)): Investigation of prime side specificity allows the synthesis of a potent inhibitor
Nogueira Santos, Jorge Alexandre
Assis, Diego M.
Gouvea, Iuri Estrada
Judice, Wagner A. S.
Izidoro, Mario Augusto
Juliano, Maria Aparecida
Juliano, Luiz [UNIFESP]
MetadataMostrar registro completo
Foot and mouth disease virus expresses its genetic information as a single polyprotein that is translated from the single-stranded RNA genome. Proteinases contained within the polyprotein then generate the mature viral proteins. the leader protease (Lb(pro)) performs the initial cleavage by freeing itself from the growing polypeptide chain; subsequently, Lb(pro) cleaves the two homologues of the host cell protein eukaryotic initiation factor 4G (eIF4G). We showed that Lb(pro) possesses specific binding sites at the non prime side from S-1 down to S-7 [Santos et al. (2009) Biochemistry, 48, 7948-7958]. Here, we demonstrate that Lb(pro) has high prime side specificity at least down to the S-5' site. Lb(pro) is thus not only one of the smallest papain-like cysteine peptidases but also one of the most specific. It can still however cleave between both K down arrow G and G down arrow R pairs. We further determined the two-step irreversible inhibition (E + I <-> EI -> E - I) kinetic parameters of two known irreversible epoxide-based inhibitors of cysteine proteinases, E64 and CA074 on Lb(pro) that show for the reversible step (E + I <-> EI) K-i = 3.4 mu M and 11.6 mu M, and for the irreversible step (EI -> E-I) k(4) = 0.16 and 0.06 min(-1), respectively. Knowledge of the Lb(pro) specificity led us to extend E64 by addition of the dipeptide R-P. This compound, termed E64-R-P-NH2, irreversibly inhibited Lb(pro) with a K-i = 30 nM and k(4) = 0.01 min(-1) and can serve as the basis for design of specific inhibitors of FMDV replication. (C) 2011 Elsevier Masson SAS. All rights reserved.
- EPM - Artigos