Open AccessPurification, crystallization and preliminary X‐ray analysis of truncated and mutant forms of VP4 protease from infectious pancreatic necrosis virus
Author(s) -
Lee Jaeyong,
Feldman Anat R.,
Chiu Elaine,
Chan Charlena,
Kim YouNa,
Delmas Bernard,
Paetzel Mark
Publication year - 2006
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309106046070
Subject(s) - infectious pancreatic necrosis virus , capsid , mutant , virus , proteases , biology , recombinant dna , protease , virology , serine protease , triclinic crystal system , microbiology and biotechnology , chemistry , enzyme , biochemistry , crystallography , crystal structure , gene
In viruses belonging to the Birnaviridae family, virus protein 4 (VP4) is the viral protease responsible for the proteolytic maturation of the polyprotein encoding the major capsid proteins (VP2 and VP3). Infectious pancreatic necrosis virus (IPNV), the prototype of the aquabirnavirus genus, is the causative agent of a contagious disease in fish which has a large economic impact on aquaculture. IPNV VP4 is a 226‐residue (24.0 kDa) serine protease that utilizes a Ser/Lys catalytic dyad mechanism (Ser633 and Lys674). Several truncated and mutant forms of VP4 were expressed in a recombinant expression system, purified and screened for crystallization. Two different crystal forms diffract beyond 2.4 Å resolution. A triclinic crystal derived from one mutant construct has unit‐cell parameters a = 41.7, b = 69.6, c = 191.6 Å, α = 93.0, β = 95.1, γ = 97.7°. A hexagonal crystal with space group P 6 1 22/ P 6 5 22 derived from another mutant construct has unit‐cell parameters a = 77.4, b = 77.4, c = 136.9 Å.