Exploiting a natural auxotrophy for genetic selection.
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ABSTRACT:
SUBMITTER: Ramage E
PROVIDER: S-EPMC3406110 | biostudies-literature | 2012 Aug
REPOSITORIES: biostudies-literature
Publications
Exploiting a natural auxotrophy for genetic selection.
Ramage Elizabeth E Gallagher Larry L Manoil Colin C
Applied and environmental microbiology 20120601 16
We exploited the natural histidine auxotrophy of Francisella species to develop hisD (encodes histidinol dehydrogenase) as a positive selection marker. A shuttle plasmid (pBR103) carrying Escherichia coli hisD and designed for cloning of PCR fragments replicated in both attenuated and highly virulent Francisella strains. During this work, we formulated a simplified defined growth medium for Francisella novicida. ...[more]
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