Previous Article | Next Article ![]()
J Virol, May 1998, p. 3916-3924, Vol. 72, No. 5
Division of Molecular Biology, The
Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
Received 7 November 1997/Accepted 1 February 1998
Retroviral integrase (IN) cleaves linear viral DNA specifically
near the ends of the DNA (cleavage reaction) and subsequently couples
the processed ends to phosphates in the target DNA (integration reaction). In vitro, IN catalyzes the disintegration reaction, which is
the reverse of the integration reaction. Ideally, we would like to test
the role of each amino acid in the IN protein. We mutagenized human
immunodeficiency virus type 2 IN in a random way using PCR mutagenesis
and generated a set of mutants in which 35% of all residues were
substituted. Mutant proteins were tested for in vitro activity, e.g.,
site-specific cleavage of viral DNA, integration, and disintegration.
Changes in 61 of the 90 proteins investigated showed no phenotypic
effect. Substitutions that changed the choice of nucleophile in the
cleavage reaction were found. These clustered around the active-site
residues Asp-116 and Glu-152. We also found alterations of amino acids
that affected cleavage and integration differentially. In addition, we
analyzed the disintegration activity of the proteins and found
substitutions of amino acids close to the dimer interface that enhanced
intermolecular disintegration activity, whereas other catalytic
activities were present at wild-type levels. This study shows the
feasibility of investigating the role of virtually any amino acid in a
protein the size of IN.
0022-538X/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.
Mutational Scan of the Human Immunodeficiency Virus
Type 2 Integrase Protein
*
Corresponding author. Mailing address: Division of
Molecular Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands. Phone: 31-20-5122081. Fax:
31-20-5122086. E-mail: rplas{at}nki.nl.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»