Date of Award:

5-1-1988

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Biology

Department name when degree awarded

Biology/Molecular Biology

Committee Chair(s)

Dennis L. Welker

Committee

Dennis L. Welker

Committee

Andy Anderson

Committee

Bill B. Barnett

Committee

Bruce Copeland

Committee

Jeff Kondo

Committee

Fred Post

Abstract

The cob-354 cobalt resistance trait of the cellular slime mold Dictyostelium discoideum was shown to be associated with a DNA amplification. The amplified DNA was present in all cob-354 strains and absent from all cobalt sensitive strains. Cured strains, derived by passage of cob-354 strains in the absence of cobaltions, lost both the amplification and the cobalt resistance. The copy number of the amplified DNA was determined to be about 50 in cobalt resistant strain HU1628 by both Southern blot and slot blot analyses. Using transverse alternating field electrophoresis and a cloned portion of the amplification as probe, a band corresponding to an extrachromosomal element of about 75 kb was identified in cob-354 strains. This band was absent in cobalt-sensitive strains. The chromosomal origin of the amplified DNA was determined to be either linkage group III or VI, therefore the cobA gene on linkage group VII is not involved in the cob-354 resistance trait. The D. discoideum transposable elements Tdd-1 and Tdd-2 are not present in the amplification, so they could not have been involved in the origin of the amplification. There was no association between the amplified DNA and D. discoideum plasmid Ddp1.

Download

Share

COinS

Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .