Cosmids: A Type of Plasmid Gene-Cloning Vector that is Packageable in vitro in Bacteriophage λ Heads
Abstract
Evidence is presented that ColE1 hybrid plasmids carrying the cohesive-end site (cos) of lambda can be used as gene cloning vectors in conjunction with the lambda in vitro packaging system of Hohn and Murray [(1977) Proc. Natl. Acad. Sci. USA 74, 3259--3263]. Due to the requirement for a large DNA molecule for efficient packaging, there is a direct selection for hybrids carrying large sections of foreign DNA. The small vector plasmids do not contribute a large background in the transduced population, which is therefore markedly enriched for large hybrid plasmids (over 90%). The efficiency of the in vitro packaging system is on the order of 10(5) hybrid clones per microgram of foreign DNA for hybrids in the 20--30 million dalton range.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- September 1978
- DOI:
- 10.1073/pnas.75.9.4242
- Bibcode:
- 1978PNAS...75.4242C