Graduation date: 1969

Graduation date: 1997

Three studies were conducted to determine the effects of cyclopropenoid fatty acids (CPFA) on the membrane components of livers of rainbow trout (Salmo gairdneri). In the first study, ¹⁴C-sterculic acid was administered by intraperitoneal injection into rainbow trout and the trout maintained for 72 hours. The labelled sterculic acid was found in choline phospholipids (CP) and ethanolamine phospholipids (EP). Smaller amounts of label were found in other microsomal membrane lipid components. No label was found associated with the proteins of the microsomal membrane. Phospholipase A₂ treatment of isolated CP and EP showed ¹⁴C-sterculic acid to be preferentially esterified to the 1-position of the glycerol backbone. In the second study, the cleavable bifunctional protein crosslinking reagent dimethyl 3,3'-dithiobispropionimidate-2HCl (DTBP) was used in an attempt to study alterations in the spatial arrangement of proteins in liver microsomal and plasma membranes that might be induced by dietary CPFA. The use of this reagent failed to yield a clear picture of protein-protein interactions in the microsomal membrane due to the formation of high molecular weight aggregates that were not resolvable on polyacrylamide gels. On the other hand, the use of DTBP failed to crosslink the proteins of the plasma membrane. In the third study, two-dimensional polyacrylamide gel electrophoresis was used to assess the effects of dietary CPFA on protein composition of trout liver microsomal and plasma membranes. Proteins were separated in the first dimension on the basis of their isoelectric points and in the second dimension on the basis of their molecular weights. No major alterations in the composition of liver microsomal or plasma membranes were found to be induced by dietary CPFA. / Graduation date: 1983

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 101-111). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Washington, 1983. / Vita. Bibliography: leaves [59]-65.

Thesis (Ph. D.)--University of Washington, 1983. / Vita. Bibliography: leaves [201]-228.

Thesis (Ph. D.)--Oregon State University, 2001. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Thesis (Ph. D.)--Washington State University, December 2009. / Title from PDF title page (viewed on Dec. 9, 2009). "College of Veterinary Medicine." Includes bibliographical references.

Some of the most devastating plant and animal pathogens belong to the oomycetes. Saprolegnia parasitica, a major pathogen of freshwater fish and the causal agent of Saprolegniosis, causes large economic losses in aquaculture due to the death of freshwater fish which contract Saprolegniosis. Losses due to Saprolegniosis are also incurred by natural fish populations. Saprolegniosis was previously controlled through the use of a biocide called malachite green, until the dye was found to have potentially carcinogenic effects. Following this discovery, the use of malachite green on fish destined to enter the food chain was banned worldwide and subsequently there has been an increase in the occurrence of Saprolegniosis. This work investigates various aspects of S. parasitica with the view to inform the development of new control strategies. Three cDNA libraries, including two interactive libraries, were analysed and bioinformatics provided valuable insight into the genes expressed not only by S. parasitica but also by the host. The annotation and expression profiles of several of these genes are described in this work and the potential of S. parasitica genes as vaccine targets is discussed. One protein, identified as a vaccine candidate, is annotated, cloned and overexpressed in order to evaluate its efficacy as a vaccine. It has been shown previously that the plant pathogenic oomycete Phytophthora infestans is able to utilise a protein localisation motif, the RxLR, in order to translocate effector proteins into the host. The question as to whether S. parasitica possesses a similar translocation system is addressed in this work. Localisation studies on an RxLR protein of S. parasitica origin are described and the microscopic interaction between S. parasitica and its host are described and attempts to optimise production of interaction structures are discussed.

No description available.