A unique undosciribed gramnegative rod is extensively characterized in this study. The cells of this unusual water isolate measure 1.2 X 6.5 microns, The most distinguishing characteristic of the bacterium is a polar tuft of 35-40 flagella that aggregate to function as a single organelle which is visible under phase contrast. Aging cells deposit poly- -hydroxybutyric acid granules which are bound by an inclusion membrane made up of four distinct layers. It also possesses an unusual exterior membrane outside the cell wall which contains large fibrils of protein running at a slight angle to the longitudinal axis of the cell. The guanosine-cytosine ratio was found to be 62.2$. The organism's taxonomic position was further investigated by immunological, morphological, and biochemical methods. It was found to be most closely akin to members of the genus Pseudo onas, although somewhat divergent from other species classified in this genus. After careful evaluation of the findings obtained during this study, the new bacterium was subsequently named Pseudomonas multiflagella.
A procedure for the isolation of malic enzyme from muscle tissue of the roundworm Ascaris suum is described. The fractionation method yields relatively large quantities of the enzyme,with a specific activity of fifteen moles of malate converted to pyruvate and carbon dioxide per min per mg at 25ยบ. Homogeneity was established with analytical ultracentrifugation, zone electrophoresis, isoelectric focusing, and rechromatography. The molecular weight of the enzyme was 250,000, and it is dissociated under several conditions into four identical monomers of 64,000 daltons. The enzyme exists as a single electrophoretic form and prefers manganous and NAD over other cations and NADP. Ammonium sulfate competes with manganous for the active site and titration with DTNB yields eight thiol groups per mole. Titration of the first four thiol groups is accompanied by a complete loss in enzyme activity. Equilibrium dialysis, product inhibition, and initial velocity studies suggest a rapid-equilibrium random sequential mechanism for the Ascaris suum malic enzyme. The presence of 1.3 binding sites per subunits was determined for L-ma late. Antisera prepared against A. suum malic enzyme reacted to a small extent with the NAD malic enzymes from two free-living nematodes, Panarellus redivivus and Turbatrix aceti. A correlation coefficient of 0.911 was obtained upon comparing the amino acid composition of A. suum and E. coli malic enzymes. Some sequence homology is predicted between these malic enzymes. The physiological interpretation favors the binding of malate initially, with the subsequent addition of NAD to the enzyme.
The rigid peptidoglycan layer of the cell wall is responsible for maintaining the structural integrity of bacteria. Antibiotics such as penicillin exert their anti-bacterial effect by inhibiting synthesis of peptodoglycan, and enzymes such as lysozyme destroy cell integrity by hydrolyzing specific bonds in the interior of this macromolecule. Defective cells can no longer withstand the high turgor pressure within the cell because they are no longer protected by a rigid wall and tend to become fragile and spherical or irregular in shape. While all bacteria are pleomorphic under certain conditions which do not normally affect other bacteria. This is exemplified by the pleomorphic growth of Azotobacter in nutrient agar or peptone-containing medium. The purpose of this investigation was to study the nature of peptone-induced pleomorphism of Azotobacter. The first phase of study dealt with the effects of poptone on the growth and morphology of A. vinelandii. Many diverse froms were observed in peptone-containing media, but it was shown that all cell types were related to the "fungoid" family of pleomorphic cells. Although Azotobacter failed to accumulate detectable levels of cell-wall precursors in response to glycine treatment, it was shown that glycine acted only on metabolically active cells. In addition, incorporation of glycine into cell wall of Azotobacter was not required for induction of pleomorphism. Methionine and aspartic acid, and to a lesser degree alanine and isoleucine, were found to competitively inhibit glycine toxicity.
The linkage relationship and arm location of the gene for greenbug resistance in the variety Will was determined by using primary trisonomics and tertiary trisomic homozygous translocations. The gene for greenbug resistance was found to be on linkage group 1 by using primary trisonomics. The gene was located on the cetromere segment of the Tl-6a translocation by using a tertiary trismoic homozygous for greenbug resistance. The data further substantiates the feasibility of using trisomics in placing genes on proper linkage groups.
Distributional data and taxonomic keys art presented for thirty-four species of Plecoptera known to occur in Oklahoma. Ten species are new records for the state. Descriptions are provided for two species new to science, Zealeuctra cherokee and Isoperla brevis, and for the previously unknown male of Strophopteryx cucullata Frison and female of Helopicus nalatus (Frison).
The objective of this investigation was to provide new and more detailed information on the life history and ecology of Neoperla clymene, through an intensive study of the species in the Brazos River, Texas.
The purpose of this study was twofold. The first was to isolate, purify, and characterize the deoxyribonucleic acid (DNA) of Azotobacter vinelandii ATCO 12837. The second was to determine if there was irreversible binding of homologous 32P labeled DNA to recipient A. vinelandii cells.
The coexistence of Dipodomys ordii and Perognathus hispidus with Peromyscus maniculatus and Reithrodontomys montanus was studied in a grassland association of central Texas. The food habits of these species were compared with information from habitat vegetation analysis in an effort to determine food selectivity and the amount and importance of niche overlap and competition among these rodents.
This study was initiated after finding two chromosomal types of Peromyscus maniculatus north and south of the Red River in Texas and Oklahoma. The problem was to explain the chromosomal variations and their implications to the systematics of the grassland subspecies of P. maniculatus in this region.
Low-frequency ultrasonic energy was utilized in an attempt to induce visible mutations in the parasitoid wasp Mormoniella vitripennis. This study demonstrates that low frequency ultrasound may be used as an effective mutagenic agent in this organism, and suggests that it may have applications to other genetic systems.
This investigation was concerned with the relationship of the slime layer material of Pseudomonas aeruginosa, Verder and Evans strain 1369, to the presumably somatic "O" type of antigen used by these authors as the base for their serological schema.
It was the purpose of this study to investigate the effect of various concentrations of IAA on the nucleic acids of Chlorella pyrenoidosa TX 7-11-05. The time during the life cycle when the greatest effect occurred was investigated by the use of synchronous cultures.
The purpose of this research was to attempt to duplicate the in vitro bactericidal test against Pseudomonas aeruginosa as reported by Bjornson and Michael and to correlate agglutinating titer of an antiserum to protective activity.
Liver cells from lymphosarcoma-bearing DBA/1J mice were shown, by parabiotic culture with normal liver cells from isologous mice, to elaborate an agent which could pass a 25 mu filter and transform the normal cells to a malignant state.
Aldolase from human heart has been purified 128-fold to a final specific activity of 11.52 units per mg. The purification procedure employed column chromatography on phosphocellulose.
This study was undertaken in order to provide further insight into the effects of artificial heating on the fisheries of a small reservoir in the Southwest. The following specific objectives were established: (1) to map the reservoir for the distribution of heated water, (2) to determine the distribution of selected species of sports, rough, and forage fish in areas affected by the effluent and in areas not affected, (3) to compare size and condition of selected species of fish from areas affected by the effluent to size and condition of fish from areas not affected, and (4) to compare food habits of channel catfish in areas affected by the effluent to the food habits of channel catfish in areas not affected.
In view of its varied concepts and interpretations, and because of the discrepancies produced by the previous utilization of polydispersed dextrans, a study using extremely narrow-range molecular weight dextran fractions was initiated to reevaluate and consolidate some of the aspects of capillary permeability. A portion of the study was performed under decreased barometric pressure in order to clarify further some of the mechanisms involved in particulate transfer across the capillary endothelial membranes. Gel filtration procedures augmented the study as an assessment of the polydispersity effects of the dextrans employed.
The purpose of the investigation was to locate the plant population which had the greatest impact on soil nitrogen in a successional sequence from newly deposited alluvia to a mature streamside forest, and to evaluate the pioneer populations in terms of their annual nitrogen contribution.
The effects of a lethal dose (1380 r) of X-irradiation on plasma and adrenal tissue histamine levels of rats were studied. The plasma histamine response was triphasic (increase at 1-3 hours, decrease at 5 and 9 hours and return to control at 24 hours post-irradiation). The adrenal tissue histamine response was found to be biphasic (decrease at 1 to 9 hours and a return to control level at 24 hours post-irradiation).
Two isoenzymes of malate dehydrogenase were isolated and partially purified from the midge larva Glyptotendipes barbipes. Differential centrifugation followed by cellulose acetate and polyacrylamide gel electrophoresis revealed one isoenzyme associated with the mitochondrial fraction and another form found only in the cytoplasm.
The problem with which this investigation is concerned is that of determining the nature of events leading to the change. of normal cells into malignant cells. The design of the study is multi-phasic: (A) to establish the presence or absence of an oncogenic virion, (B) to demonstrate by use of the electron microscopy any ultracellular alteration in malignant or transformed tissues, (C) to investigate the nature of the transforming agent in the murine lymphosarcoma, and (D) to employ various methods to demonstrate cellular transformations in vivo and in vitro. It is concluded that the transforming and tumorinducing agent in this' investigation was not a virion, but an infectious ribonucleic acid genome or a segment of a viral genome which had become integrated into the genome of the mouse cells. The vision has lost its ability to form a protein coat; therefore it is not demonstrable as a virion. But the ribonucleic acid is able to infect other cells and transform them from normal to neoplastic tissues.
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