Leukotoxin gene of pasteurella haemolytica
US5055400A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1986 |
| Grant date | Oct 8, 1991 |
| Priority date | — |
| Expiry date | Nov 26, 2006 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K39/00
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The gene coding for Pasteurella haemolytica leukotoxin can be cloned in a plasmic expressed in Escherichia coli. The leukotoxin gene can be isolated from a clone bank of P. haemolytica. The clone bank is constructed by partial digestion of genomic DNA. The resultant 5 to 10 kilobase-pair fragments are ligated into plasmid vector pBR322. The resultant clones are screened for the production of P. haemolytica soluble antigens by a colony enzyme-linked immunosorbent assay blot method with a rabbit antiserum raised against the soluble antigens. The clones producing P. haemolytica soluble antigens are then analyzed for the production of the leukotoxin by a cytotoxicity assay with cells from a bovine leukemia-derived B-lymphocyte cell line as the target cells. Positive clones are identified, and subsequent restriction analysis of the recombinant plasmids shows the same insert DNA is cloned in the plasmid vector. The DNA sequence analysis of the insert DNA reveals regions coding for the leukotoxin.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.