Restrictocin-like ribotoxin analogues comprising only one cysteine available for covalent linkage to a partner
US5439815A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 13, 1992 |
| Grant date | Aug 8, 1995 |
| Priority date | — |
| Expiry date | Jul 13, 2012 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K38/00
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Ribotoxins, such as restrictocin, mitogillin and alpha-sarcin which do not contain a cysteine for linkage to antibodies for immunotoxin production need to be modified for such linkage without compromising biological activity. Protein analogues of such native ribotoxins are provided in which both the analogue and the native ribotoxin can cleave only a single phosphodiester bond of 28S rRNA in a 60S ribosomal subunit and in which the analogue comprises only one cysteine available from covalent linkage to a partner, such as an antibody, which cysteine is not present in the native ribotoxin. Especially preferred analogues are restrictocin Cys 13, Cys 82, Cys 106 and Cys 110 and restrictocin Cys 150-Gly151. Corresponding DNA sequences, vectors, host cells, immunotoxins and pharmaceutical compositions are also claimed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.