Portland State University. Department of Biology
John W. Myers
Date of Award
Master of Science (M.S.) in Biology
1 online resource; digitized manuscript
Azotobacter, Genetic transformation
Previous methods for genetic transformation in Azotobacter vinelandii have employed poorly defined genetic markers or crude DNA extracts. An improved transformation technique has been developed for use in Azotobacter. The technique was used to transform several strains of Azotobacter with DNA carrying a defined genetic marker. A method for isolating pure, high molecular weight, biologically active DNA from Azotobacter is also presented. Purity of the extracted DNA was determined by standard chemical assays. The molecular weight was determined by boundary sedimentation techniques to be 18.2 megadaltons. DNA was obtained from several mutant strains of Azotobacter. Biological activity of these samples was demonstrated by using them to accomplish both intra- and interstrain transformation. Thermal denaturation profiles of several DNA samples are presented, from which guanine plus cytosine content was determined. Among the Azotobacter species examined, GC content ranged from 65.1 to 67.8%. The use of the new transformation and DNA isolation methods in taxonomic and mapping studies is discussed.
Voth, Wayne H., "Genetic Transformation Among Azotobacter Species" (1977). Dissertations and Theses. Paper 2617.