ISSN:
1432-072X
Keywords:
Genetic transformation
;
Plasmid
;
Recombination
;
pBR322
;
Chromosomal integration
;
β-Lactamase
;
Azotobacter vinelandii
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The soil bacterium Azotobacter vinelandii was genetically transformed by chromosomal integration to ampicillin and/or tetracycline resistance using restriction endonuclease-linearized plasmids. Polyacrylamide gel electrophoresis of protein extracts from three independently isolated ampicillin resistant transformants showed the presence of a 28 Kd band which is the approximate size of the ampicillin resistance gene product (i.e., β-lactamase). Moreover, with nitrocefin, a chromogenic cephalosporin, as a substrate, it was shown that all of the ampicillin resistant transformants produced functional β-lactamase. DNA hybridization showed that the chromosomal DNA from transformed cells contained plasmid DNA sequences at discrete sites. Growth experiments indicated that stable A. vinelandii transformants that carry functional integrated DNA were physiologically impaired.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00446925
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