Premium
Cleavage of supercoiled double‐stranded DNA by several ribosome‐inactivating proteins in vitro
Author(s) -
Ling Jun,
Liu Wang-yi,
Wang T.P.
Publication year - 1994
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(94)00421-8
Subject(s) - dna , dna supercoil , ricin , ribonuclease , cleave , rna , chemistry , ribosome , biochemistry , in vitro , depurination , microbiology and biotechnology , biology , dna replication , toxin , gene
Several ribosome‐inactivating proteins (RIPs), such as ricin (including its A‐chain), luffin, cinnamomin and camphorin, were found to express enzymatic activity to cleave supercoiled double‐stranded DNA. In particular, α‐sarcin, a RIP with a novel ribonuclease activity, was first proved to have this activity. They convert supercoiled DNA into a nicked circular conformation at low concentrations and further into a linear form at high concentrations: they have no effect on linear DNA. Although intact type II RIPs exhibited no RNA N ‐glucosidase activity, they were detected to cleave supercoiled DNA. Even if ricin A‐chain was treated by boiling, its activity on supercoiled DNA was largely retained.