Hepatitis A virus polyprotein processing by Escherichia coli proteases

Abstract

Hepatitis A virus (HAV) encodes a single polyprotein, which is post-translationally processed. This processing represents an essential step in capsid formation. The virus possesses only one protease, 3C, responsible for all cleavages, except for that at the VP1/2A junction region, which is processed by cellular proteases. In this study, data demonstrates that HAV polyprotein processing by Escherichia coli protease(s) leads to the formation of particulate structures. P3 polyprotein processing in E. coli is not dependent on an active 3C protease : the same processing pattern is observed with wild-type 3C or with several 3C mutants. However, this processing pattern is temperature-dependant, since it differs at 37 or 42 mC. The bacterial protease(s) cleave scissile bonds other than those of HAV ; this contributes to the low efficiency of particle formation.

Hepatitis A Virus Adaptation to Cellular Shutoff Is Driven by Dynamic Adjustments of Codon Usage and Results in the Selection of Populations with Altered Capsids

“…All MAbs were used at the highest dilution yielding recognition of the pHM175 43c strain of HAV. This strain, although resistant to neutralization by MAb K24F2 (26), still shows antibody binding (30) and is well recognized by ELISA at a high concentration of the antibody (31). Thus, the dilutions used were 1/10,000 for H7C27 and K34C8 MAbs and 1/250 for K24F2 MAb.…”

Use of Fluorescence Resonance Energy Transfer for Rapid Detection of Enteroviral Infection In Vivo

“…In this study, we demonstrated that a reporter cell line expressing fluorogenic protease substrate responds well to viral infection, and the infected cells could be detected easily through fluorescent microscopy. The reporter cells responded to all three enteroviruses tested with different sensitivities and did not respond to HAV, which is also a member of Picornaviridae, but it does not encode protease 2A (37). The reporter cells achieved the same detection limit for PV1 and EV11 (Յ10 PFU) but had a higher detection limit for CVB6 (Յ100 PFU) ( Table 1).…”

Molecular Basis of the Behavior of Hepatitis A Virus Exposed to High Hydrostatic Pressure

“…The morphogenesis pathway of the different populations was analyzed as previously described (24,25). Portions (500 l) of concentrated viral stocks were layered onto a 15 to 45% sucrose gradient in TNMg buffer (20 mM Tris-HCl, 10 mM NaCl, 50 mM MgCl 2 [pH 6.7]) and spun at 205,000 ϫ g for 165 min.…”