Purification and properties of nuclease gamma from Ustilago maydis.

TitlePurification and properties of nuclease gamma from Ustilago maydis.
Publication TypeJournal Article
Year of Publication1984
AuthorsYarnall M, Rowe TC, Holloman WK
JournalJ Biol Chem
Volume259
Issue5
Pagination3026-32
Date Published1984 Mar 10
ISSN0021-9258
KeywordsBasidiomycota, Cations, Divalent, Chromatography, Gel, Endodeoxyribonucleases, Fungal Proteins, Molecular Weight, Substrate Specificity, Ustilago
Abstract

We have purified an acid-soluble DNA endonuclease, termed nuclease gamma, from Ustilago cell extracts. The enzyme is nearly homogeneous, purified 1700-fold. The protein appears to be globular with a molecular weight in the range 17,000 to 21,000. It requires a divalent cation and is optimally active at slightly alkaline pH. The enzyme prefers duplex DNA as substrate but will slowly cleave single-stranded DNA. Cleavage of covalently closed duplex DNA is unaltered by changes in superhelix density. Divalent cations direct the mode by which the enzyme cleaves duplex DNA. When Mg2+ or Ca2+ is added, the enzyme nicks one strand of the duplex. When Mn2+, Co2+, or Zn2+ is added, the enzyme can introduce double strand breaks. Oligonucleotides terminated with 5'-phosphoryl and 3'-hydroxyl groups are the products of hydrolysis. DNA fragments generated can be religated to linear pBR322 DNA with completely base-paired ends.

Alternate JournalJ. Biol. Chem.
PubMed ID6699006
Grant ListGM27103 / GM / NIGMS NIH HHS / United States

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