title: Herpes simplex virus type 1 DNase: functional analysis of the enzyme expressed by recombinant baculovirus.
abstract: Herpes simplex virus type 1 DNase (HSV-1 DNase) was expressed in insect cells by recombinant baculovirus (NPVUL12) and purified by a combination of anionic exchanger chromatography and gel filtration. Two polypeptides of 85 and 75 kD, whose ratio varied during purification, were induced 24 h after infection. The 75-kD protein was isolated and shown to possess catalytic activity. Gel filtration analysis indicated that the active form of the enzyme at an ionic strength of I = 0.3 is a dimeric protein with an apparent molecular weight of 130,000. The recombinant enzyme exhibited the overall characteristics of the native enzyme such as 5'-3' exonuclease and endonuclease activities with a preferred degradation of DNA. In the absence of extraneously added Mg2+, the enzyme was capable of removing mononucleotides from 5'-end-labeled DNA, but not from RNA and 3'-end-labeled DNA. The peculiar mechanism of double-strand DNA degradation suggests a specific role of HSV-1 DNase in DNA recombination processes during viral replication.
authors.affiliation: Deutsches Krebsforschungszentrum, Genomforschung und Bioinformatik, Heidelberg, Deutschland.
authors.forename: E
authors.initials: E
authors.lastname: Kehm
authors.forename: M
authors.initials: M
authors.lastname: Göksu
authors.forename: S
authors.initials: S
authors.lastname: Bayer
authors.forename: C W
authors.initials: CW
authors.lastname: Knopf
mesh_terms: D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D006224:Cricetinae; D004279:DNA, Viral / Q000235:genetics / Q000378:metabolism; D003851:Deoxyribonucleases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019281:Dimerization; D015870:Gene Expression; D005814:Genes, Viral; D018259:Herpesvirus 1, Human / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D008970:Molecular Weight; D017924:Nucleopolyhedroviruses / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic; D018411:Spodoptera; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D011994:Recombinant Proteins; D003851:Deoxyribonucleases