A DNA nicking-closing enzyme encapsidated in vaccinia virus: partial purification and properties.
AUTOR(ES)
Bauer, W R
RESUMO
Vaccinia virus cores contain an activity which is able to relax both left-and right-handed superhelical DNA. This virus-specific nicking closing enzyme has been highly purified and differs from the corresponding host enzyme in salt optimum, in sedimentation coefficient, and in polypeptide composition as determined on sodium dodecyl sulfate/polyacrylamide gels. The enzyme is probably newly synthesized after the cessation of host protein synthesis which follows virus infection. The most highly purified preparation contains two polypeptides, one of molecular weight 24,000 and the other 35,000. The former polypeptide is a major constituent of the virus (7% of total protein by weight), whereas the latter is present in a much smaller amount (0.2%). Chromatography with denatured DNA-cellulose reveals that the activity is predominately associated with those fractions enriched in the polypeptide of greater molecular weight.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=431023Documentos Relacionados
- Purification of a DNA nicking-closing enzyme from mouse L cells.
- Nicking-closing enzyme assembles nucleosome-like structures in vitro.
- Breakage of single-stranded DNA by rat liver nicking-closing enzyme with the formation of a DNA-enzyme complex.
- Nicking-closing enzyme is associated with SV40 DNA in vivo as a sodium dodecyl sulfate-resistant complex.
- AMP-dependent DNA relaxation catalyzed by DNA ligase occurs by a nicking-closing mechanism.