Date of Award
8-2000
Degree Name
Master of Science
Department
Biological Sciences
First Advisor
Dr. Silvia Rossbach
Second Advisor
Dr. Susan Stapleton
Third Advisor
Dr. Bruce Bejcek
Access Setting
Masters Thesis-Open Access
Abstract
This thesis describes the isolation and characterization of a region containing several genes involved in metal tolerance in the common soil bacterium, Pseudomonas fluorescens ATCC 13525. The DNA region was identified in a cadmium and zinc sensitive mutant, 45-B10, which contains a lacZ-based reporter gene transposon Tn5-B20 inserted in the chromosome. The DNA surrounding the transposon was cloned from this mutant strain and DNA sequencing of this region revealed seven genes that share similarity with genes whose products are involved in the cation-proton antiporter efflux system of other Gram-negative bacteria. Complete DNA sequence was obtained from four of these genes, czyO, czyR, czyS and czyA. Defined mutations in each of these genes were generated in the chromosome of P. fluorescens via gene replacements. The gene replacement mutants were found to be more sensitive to cadmium or zinc compared to wild type. The comparison of DNA similarity and the phenotypic analysis of the mutants suggest that these genes play a role in metal homeostasis in P. fluorescens.
Recommended Citation
Feng, Szi Fei, "Isolation and Characterization of a Genetic Locus That Confers Tolerance to Cadmium and Zinc in Pseudomonas Fluorescens" (2000). Masters Theses. 5053.
https://scholarworks.wmich.edu/masters_theses/5053