Microbiology Commons^™

Biochemical Properties Of Salmonella Potsdam Bacteriophage P4/2, Clyde L. Roggenkamp

Loma Linda University Electronic Theses, Dissertations & Projects

Over 90% recovery of phage P4/2 was realized with differential centrifugation concentration and purification, whereas only about 16% was recovered from the aqueous two-phase polymer - Genetron - ECTEOLA-cellulose column system. Purity of preparations was greatest with the density gradient centrifugation (A₂₆₀ = 2.66 and A₂₈₀ = 1.80 per 10¹² plaque-forming units). With the chemical system of concentration and purification followed by an ECTEOLA anion exchange run, the A₂₆₀ was 6.6 and the A₂₈₀ was 4.3.

Three tests were employed to determine the configuration of P4/2 DNA: (1) a formalin denaturation test, (2) a thermal …

Nocturnal Flights Of Triatoma Protracta (Uhler) As Indicated By Collections At Black Light Traps : (Hemiptera: Reduviidae: Triatominae), Robert D. Sjogren

Loma Linda University Electronic Theses, Dissertations & Projects

An investigation into the environmental and ethological factors relating to summer flights of Triatoma protracta protracta (Uhler) was performed utilizing black light traps of original design. Field observations were conducted on 51 evenings during the period June 1 to October 31, 1964. The traps were operated on a surveillance basis for the remainder of a twelve month period.

A total of 398 adult Triatoma protracta were collected in traps around a residence located in the chaparral covered foothills 10 miles east of Redlands, California. In addition to observations on field behavior, laboratory dissections were performed on each bug to obtain …

Ultraviolet Induction Properties Of Salmonella Potsdam Bacteriophages, Berney Roy Neufeld

Loma Linda University Electronic Theses, Dissertations & Projects

Three lysogenic strains of Salmonella potsdam were studied to determine whether or not they were inducible by ultraviolet light under certain conditions. The strains examined were SP3, SP4, and SP9. SP3 and SP4 contained a single prophage each and SP9 contained two prophages P9a and P9c. The ultraviolet light sensitivities of each of these lysogenic strains and the indicator strain SP2 were also examined.

All three lysogenic strains were found to be inducible. SP3 was induced an average of 3.59% and SP4 an average of 2.21%. The difference between the induction percentages of SP3 and SP4 was not statistically significant. …

Investigation In The Physiology Of The Spore Formation Of Pseudoples Trifolii (Rostr.) And Petr., Emory S. Crosby

Masters Theses & Specialist Projects

Plant pathologists have worked to some extent for many years in an attempt to describe the complete physiology of the organism responsible for pepper spot of clover, particularly as found on white clover (Trifolium repens, L.). These works have not been extensive or concentrated and at the present time, no definite conclusions have been reached.

The causal agent of pepper spot of clover is Pseudoples trifolii (Rostr.).

Pseudoples trifolii usually is found parasitizing clover in the early spring and continues throughout the spring until the temperature exceeds thirty degrees centigrade. Elliott established that Pseudoples trifolii will not produce infectious spores …

Studies On The Microcrustacea Of Three Montane Lakes In Glacier National Park, Montana, Robert O. Megard

Biology ETDs

Grinnell Lake, Lake Josephine, and Swiftcurrent Lake, at an elevation of approximately 5,000 feet in northwestern Montana, are comparable with lakes in the montane zone defined by Pennak for lakes at elevations between 8,200 feet and 10,500 feet in the Rocky Mountains of northern Colorado. Five species of Copepoda, six Cladocera, and four Ostracoda were collected in the lakes studied. The population of microcrustacea in these lakes was most dense in or slightly above the masses of rooted aquatic vegetation growing to a height of six to 10 inches above the bottom wherever the water was between three feet and …

Molds And Bacteria In House Dust And Furniture Stuffing, Mary Ann Swaebly

Journal of the Minnesota Academy of Science

No abstract provided.

The Chromosomes Of The Yeast Cell, Donald William Penn

Bachelors’ Theses

Saccharomyces cerevisiae has long been a fungus of economic importance in the baking and beverage fields. A large amount of research has been done on this yeast cytologically and biochemically. However, due to its small size and difficulty in staining, the cytology of the yeast cell remains somewhat in question. Chromosomes and division figures have been demonstrated by several workers, but there still remain sharp differences of opinion as to the nature of the nucleus. Recent work on the genetics of yeast has shown evidence of chromosome division similar to that occurring in higher plants and studies of linkage have …

Utilization Of Peptones And Peptone Fractions By Bacteria, Margaret E. Mcmaster

Open Access Master's Theses (through 2010)

An attempt was made to determine the minimum concentration of the different peptones which are necessary to support the growth of a group of aerobic microorganisms. The medium for this experiment was semi-solid glucose peptone agar, with the peptone being varied in amount and kind.

1. The growth supporting properties of the peptones under investigation varied a great deal.
2. The minimum concentration of peptone necessary for the growth of Shigella dysenteriae, Proteus vulgaris, Streptococcus lactis, and Salmonella pullorum was determined.
3. Peptones appear to contain a substance which is toxic to Salmonella pullorum or else they lack a growth …

Nutritional Studies Of Protozoa, Alfred M. Elliott

Journal of the Minnesota Academy of Science

No abstract provided.

Amoeba, External Parasites On Hydra, Wendel Luetmer

Journal of the Minnesota Academy of Science

No abstract provided.

Scientific Discoveries Concerned With Pathogenic Micro-Organisms, Matilda Mary Steinbrecher

Bachelors’ Theses

Stand where you choose some calm night and look up into the great dome of the sky. Realize that those countless stars, once believed to regulate our destinies, have been proven by science to be other worlds more or less like ours. Let your thoughts wander on to objects near at hand. You see the rocks and soil and plants as did mankind for ages back; but where they not so long back saw nought else, you see rocks breaking into fertile soil and realize that minute living beings are responsible. You have come to understand that all the nitrogen …

Critique Of Influence Of Mineral Manures Upon The Mineral And Nitrogen Composition Of Plants, Dan Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Variation in quality of plants of the same species has been known to exist for a long time. The influences bringing about such variation have been studied only comparatively recently. Quantity production has been given the greatest amount of attention as a rule, the beneficial results from the use of manures being judged by the quantity of produce. Some plants, however, varied so widely in composition, and the variations were of such paramount importance, that the influences affecting quality began to receive some attention. Of this type of plants may be mentioned sugar-beets and tobacco. There was also the hope …

Sanitation Of Drinking Water, Kentucky Library Research Collections

Research Collections

The Arena was an American literary and political magazine founded by journalist, Benjamin Flower. Flower wanted the magazine to "agitate, educate, organize," he used investigative techniques to obtain information to bring about social, economic and political reform. This article focuses on the contamination of drinking water and its role in spreading diseases.