Life Sciences Commons^™

A Study Of Rna Bacteriophage 7s Infection Of Pseudomonas Aeruginosa, Deanne Benson

Dissertations and Theses

A study was conducted to find the effect of magnesium, calcium, manganese and zinc ions on the infection of Psudomonas aeruginosa strain 1C by RNA bacteriophage 7s. When an 18 hour progeny experiment was performed, it was found that magnesium, calcium and manganese had different effects on bacteriophage production and was dependent on the bacterial growth conditions. RNA bacteriophage 7s progeny production was significantly enhanced by the addition of magnesium to cultures of Psudomonas aeruginosa 1C grown in a magnesium deficient medium. Under these environmental conditions there was a slight increase in progeny in the presence of calcium. When Psudomonas …

Eutamias Minimus And E. Amoenus: Morphological Cluster Analysis, Sandra Elaine Anderson

Dissertations and Theses

Cluster analysis of a large body of data on 180 Oregon specimens of Eutamias minimus and E. amoenus suggest that overall length of skull, basal length of skull and length of palate are taxonomically critical. If their sum is less than 71.3 millimeters the animal is E. minimus. If the sum is greater than 72.7 millimeters the animal is E. amoenus. If the sum is between 71.3 and 72.7 millimeters, other factors must be considered before the animal can be identified. Of the 180 specimens, there were 60 E. minimus, 114 E. amoenus, 2 hybrids, 2 …

Enzyme Reactions Using Ureidosuccinate As A Substrate During Pyrimidine Biosynthesis And Degradation In Cl. Oroticum, Penny Amy

Dissertations and Theses

Cells of Clostridium oroticum, an anaerobic bacterium, were grown on orotate as a carbon and energy source. Ureidosuccinase, an inducible enzyme in the pathway for pyrimidine degradation has been shown to convert ureidosuccinate to aspartate, CO₂ and NH₃ as reported by Liebenmm and Kornberg (7). Aspartate and CO₂ were formed in approximately a 1:1 ratio from ureidosuccinase activity.

Ureidosuccinase was found to be a Mn+² requiring enzyme with a pH optimum of approximately pH 6.5. Enzyme activity is labile to O₂, temperature, pH, dilution and high ionic strength. The optimum conditions for storage …

Infection Of Smallmouth Bass And Goldfish By Two Species Of Saprolegnia, Cheryl A. Mcginley

Dissertations and Theses

This study consisted of several experiments designed to compare the ability of two species of fungi, Saprolegnia ferax and S. parasitica to grow on two species of fish, smallmouth bass (Micropterus dolomieui) and goldfish (Carassius auratus), and to determine the criteria necessary for the development of these infections.

The results indicate that water in the fish tanks must be slightly acid (pH 6), warm (22°C), nonmoving, and that the fish must be wounded in order for fungal infection to occur. Cool water (18°C) and moving water, caused by aeration and filtration, are detrimental to fungal colony formation so that no …

Effects Of The Nerve During The Dedifferentiative Phase Of Limb Regeneration In The Mexican Axolotl, Ambystoma Mexicanum, Roberta Gail Wald

Dissertations and Theses

It is known that nerves are particularly critical during the early or dedifferentiative phase of limb regeneration. During this period in the innervated limb, cells just proximal to the amputation surface dedifferentiate, migrate to the limb tip, and undergo mitosis. These processes give rise to a population of undifferentiated mesenchymatous cells capable of redifferentiating into the missing components of the newly forming regenerate. The consequences of denervation stand in stark contrast to the normal events occurring in the innervated limb, because neither a blastema nor a regenerate forms.

Results from this study indicate that during the early portion of the …

Physiological And Behavior Studies Of Thelepus Crispus And Its Commensal Halosydna Brevisetosa, John B. Morgan

Dissertations and Theses

Chemical, physical and physiological interactions between the marine commensal scaleworm Halosydna brevisetosa Kinberg and its terebellid host, Thelepus crispus Johnson were investigated. In an experiment designed to test for chemical attraction between the host and commensal, Halosydna were unable to identify the arm in a U-tube choice apparatus leading to the host. In 50 trials, 54% of the commensals crawled into the flow of water from their hosts. Other observations showed that Halosydna made contact with the host by random encounter. After contact, commensals followed tentacles down into the host’s tube and took up a characteristic position along the dorsum …

An Investigation Of Infection Mechanisms Of Arceuthobium Campylopodum, Annabella Jaramillo Garcia

Dissertations and Theses

Wound periderm is formed by Juniperus occidentalis and Calocedrus decurrens in resistance to infection by the dwarf mistletoe Arceuthobium campylopodum. The pattern of wound periderm formation suggests that chemical as well as mechanical factors are involved. The concentration of hydrolases in the radicular apex of the parasite suggests that they may facilitate the penetration process by which dwarf mistletoes infect their hosts. Emzymatic assistance may also provide a partial explanation for the specificity with which dwarf mistletoes are adapted to given hosts. These resistance responses by the the non-host species were compared with the normal infection process Pinus ponderosa.