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A plasmid vector with a selectable marker for halophilic archaebacteria.

M L Holmes·M L Dyall-Smith
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Abstract

A mutant resistant to the gyrase inhibitor novobiocin was selected from a halophilic archaebacterium belonging to the genus Haloferax. Chromosomal DNA from this mutant was able to transform wild-type cells to novobiocin resistance, and these transformants formed visible colonies in 3 to 4 days on selective plates. The resistance gene was isolated on a 6.7-kilobase DNA KpnI fragment, which was inserted into a cryptic multicopy plasmid (pHK2) derived from the same host strain. The recombinant plasmid transformed wild-type cells at a high efficiency (greater than 10(6)/micrograms), was stably maintained, and could readily be reisolated from transformants. It could also transform Halobacterium volcanii and appears to be a useful system for genetic analysis in halophilic archaebacteria.

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ArchaeaBacteriaBase SequenceDNA, BacterialDrug Resistance, MicrobialEscherichia coliGenetic VectorsHalobacteriumMolecular Sequence DataNovobiocinPlasmidsRNA, RibosomalRestriction MappingTransformation, BacterialJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

M L Holmes, M L Dyall-Smith. 1990. A plasmid vector with a selectable marker for halophilic archaebacteria.. https://doi.org/10.1128/jb.172.2.756-761.1990

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