Point mutation in avian sarcoma leukaemia virus protease which increases its activity but impairs infectious virus production

G. Arad, M. Chorev, A. Shtorch, A. Goldblum, M. Kotler*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

10 Scopus citations

Abstract

The retrovirus protease (PR), an aspartic PR, is composed of two identical subunits, each containing a conserved tripeptide sequence present at the active site of the enzyme. Asp-Ser-Gly is found in avian sarcoma leukaemia viruses (ASLV) and Asp-Thr-Gly in mam-malian oncoretroviruses. We have mutated the conserved sequence at the active site of ASLV PR by converting the Ser and Gly residues to Thr and Ala, respectively. Replacement of Gly with Ala yielded an ASLV PR devoid of proteolytic activity. The Ser to Thr conversion did not alter the substrate specificity of the enzyme. Both wild-type and mutated PRs correctly cleaved viral precursors expressed in bacterial cells, as well as synthetic peptides homologous to ASLV and human immunodeficiency virus type 1 cleavage sites. Bacterially produced ASLV PR with Thr instead of Ser had increased enzymatic activity, as shown by hydrolysis of synthetic peptides. However, this mutation reduced the production of reverse transcriptase-containing particles and infectious virus following transfection of permissive cells with virus DNA.

Original languageAmerican English
Pages (from-to)1917-1925
Number of pages9
JournalJournal of General Virology
Volume76
Issue number8
DOIs
StatePublished - 1995

Fingerprint

Dive into the research topics of 'Point mutation in avian sarcoma leukaemia virus protease which increases its activity but impairs infectious virus production'. Together they form a unique fingerprint.

Cite this