Steady-State Cleavage Kinetics for Dengue Virus Type 2 Ns2b-Ns3(Pro) Serine Protease With Synthetic Peptides

Author(s): Rabuesak Khumthong, Pornwarat Niyomrattanakit, Santad Chanprapaph, Chanan Angsuthanasombat, Sakol Panyim, Gerd Katzenmeier.

Journal Name: Protein & Peptide Letters

Volume 10 , Issue 1 , 2003

Become EABM
Become Reviewer

Abstract:

The N-terminal part of the NS3 protein from dengue virus contains a trypsin-like serine protease responsible for processing the nonstructural region of the viral polyprotein. Enzymatic activity of the NS2B-NS3(pro) precursor incorporating a full-length NS2B cofactor of dengue virus type 2 was examined by using synthetic dodecamer peptide substrates encompassing native cleavage sequences of the NS2A/NS2B, NS2B / NS3, NS3 / NS4A and NS4B / NS5 polyprotein junctions. Cleavage of the dansylated substrates was monitored by a HPLC-based assay and kinetic parameters for Km, kcat and kcat / Km were obtained. The data presented here show that NS2B-NS3(pro) expressed in recombinant E. coli can be renatured to an active protease which reacts in the absence of microsomal membranes with all 4 substrate peptides, albeit the molecule does not exhibit autoproteolytic processing at the NS2B / NS3 site. A marked difference in cleavage efficiency was found for the NS2B / NS3 substrate and the remaining 3 peptides based on the NS2A / NS2B, NS3 / NS4A and NS4A / NS5 cleavage sites.

Keywords: dengue virus, ns2b-ns3, serine protease, peptide, substrate, assay, kinetic, cleavage kinetics

Rights & PermissionsPrintExport Cite as


Article Details

VOLUME: 10
ISSUE: 1
Year: 2003
Page: [19 - 26]
Pages: 8
DOI: 10.2174/0929866033408228

Article Metrics

PDF: 31