Browsing by Subject "Bacillus subtilis"
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Item A comparative study of the actions of coumarin derivatives in their excited states on DNA: genetic consequences for Bacillus subtilis.(Texas Tech University, 1974-08) Harter, Marian LNot availableItem Amino Acid metabolism and Competence Development in Bacillus Subtilis(Texas Tech University, 1972-05) Unfred, David WayneNot Available.Item Aminopeptidases of Bacillus subtilis(Texas Tech University, 1975-05) Desmond, Edward PaulThe production of aminopeptidases, intracellularly or extracellularly, by many bacterial species has been noted (4, 5, 28). In the genus Bacillus, Aubert and Millet (2) reported an aminopeptidase in cells of _B. megaterium which increased five-fold in activity during sporulation. Hall, Kunkel and Prescott reported an extracellular aminopeptidase in culture filtrated of B. licheniformis which has a pH optimum of 8.5 - 9, and was activated by Co ions (15). Two aminopeptidases haye also been reported in B^. stearothermophi 1 us (25, 29). In B. subtilis, Matsumura, et al_., (23) and ainamiura, et al., (24) found two aminopeptidases in cells of this species which could be separated from each other on columns of diethylaminoethyl (DEAE) cellulose. Minamiura, ejt aj, reported that one of these two enzymes hydrolyzed D-leucyl-glycyl-glycine. Wagner, Chung, and Ray (32) described an extracellular aminopeptidase in cultures of B. subtilis which they contend is secreted, under appropriate conditions, by intact cells into the medium. The pH optimum of this enzyme was 8.0, and Co was found to activate it.Item Bioenergetics of DNA Transport in Bacillus Subtilis(Texas Tech University, 1971-12) LaRue, Michael KingNot Available.Item Defining the Constellation of RNA Elements That Associate with Bacillus Subtilis HFQ(2013-01-17) Dambach, Michael David; Winkler, Wade C., Ph.D.Bacteria utilize a wide variety of genetic regulatory strategies in order to sense and respond to various environmental fluctuations in nutrient availability, temperature, salinity, and oxygen among others. As such, bacterial species have evolved highly coordinated and tightly regulated systems as a means of efficiently responding to potentially deleterious changes in environmental conditions. Traditionally DNA binding transcriptions factors were thought to be the primary means by which the cell executes a selective genetic response. However, the advent of microarray and next generation sequencing platforms, coupled with the wealth of sequenced genomes and powerful bioinformatics have revealed that RNA mediated post transcriptional gene regulation is wide spread in bacterial species and may in fact rival protein based regulatory systems in scope and breadth. RNA mediated post transcriptional gene regulation is broadly divided into two categories-those in which the RNA element is transcribed with the mRNA it regulates (cis-acting regulatory RNAs) or those which are transcribed independently from the gene that they regulate (trans-acting regulatory RNAs). In general cis-acting RNA elements are embedded within a 5’ UTR of a gene that they regulate and may or may not require a protein cofactor to execute genetic regulation. Whereas, trans-acting regulatory RNAs, also known as sRNAs, function via base pairing with their target mRNA and this usually requires the protein chaperone Hfq. Hfq mediated gene regulation is poorly understood in Gram-positive organism, thus I undertook studies of this protein in the model Gram-positive organism Bacillus subtilis. I used co-immunoprecipitation and deep-sequencing to define the suite of RNA elements that associate with this regulatory protein. In addition I performed global transcriptomic studies on an Hfq deletion mutant in order to identify genes that are regulated via Hfq. These studies identified sRNAs that may be involved with sporulation. This led me to analyze the transcriptomic profile of Bacillus subtilis spores in an attempt to identify new sRNA regulators.Item Detection of DNA-Damaging Compounds in Concentrated Wastewater(Texas Tech University, 1981-08) Gorman, Sally AnnNot Available.Item DNA transformation and mutagenesis studies on dithane with Bacillus subtilis repair-deficient strains(Texas Tech University, 1980-08) Lee, Ming-chouNot availableItem DNA-damaging effects of 1,2-dimethylhydrazine on Bacillus subtilis(Texas Tech University, 1978-08) Hoffman, Kent M.The DNA-damaging potential of the compound 1,2-diinethylhydrazine (DMH) was investigated using the Bacillus subtilis tester systems, which included the DNA repair assay, DNA-DMH binding studies, and DNA transformation. The compound was shown to specifically inhibit the growth of recombination deficient strains of B^. subtilis more than the wild type strain. For DNA-damaging activity, the pH had to be above 6.5. Below this pH, the compound did not appear to be active. Activation with rat-liver homogenate did not increase the DNA-damaging activity. The absorption spectrum of DNA isolated from the recombination deficient strain, mc-1, was altered when the DNA was challenged 2J1 vivo with DMH but not when challenged iji vitro. Transformation with treated DNA from this strain was reduced compared to DNA isolated from an unchallenged culture.Item In vitro polyketide biocatalysis : triketide building-blocks and enzymology(2013-05) Harper, Andrew David; Keatinge-Clay, Adrian TristanPolyketide products are useful compounds to research and industry but can be difficult to access due to their richness in stereogenic centers. Type I polyketide synthases offer unique engineering opportunities to access natural stereocontrol and resultant complex compounds. The development of a controlled in vitro platform based around type I polyketide synthases is described. It has been used to produce a small library of polyketide fragments on an unprecedented and synthetically-relevant scale and explore polyketide synthase enzymology.Item Quantitation of a mutagenic metabolite produced from 1,2-dimethylhydrazine during lipid influenced colon cancer development by a Bacillus subtilis assay(Texas Tech University, 1981-05) Wargovich, Michael JohnStudies were conducted to determine if the impact of the growth management plan adopted by Petaluma, California in 1972 for a five-year period, accomplished the goals and objectives established at the onset of the program. Uniform data were gathered for Petaluma and four control cities of similar size and location. The data were tested using Friedman's two-way analysis of variance by ranks test to determine likeness between the cities. Thirteen variables were selected to obtain an overview of characteristics relating to general information, revenue data, expenditure data, and debt information. The results of these tests indicated the five communities appeared strikingly similar in the period 1940-1970. Since Petaluma adopted its growth management scheme in 1972, the cities tested appear significantly different. To determine if that difference could be explained due to the growth management policies of Petaluma, five specific goals for the plan which were given by the city as reasons for taking the new planning approach were stated as hypotheses and tested. It was originally stated that adoption of a growth management planning scheme would lower the tax burden on the local taxpayer. The results of the tests do not support this statement; in fact, it appears the plan increased the local tax burden and reduced the citizens cost : benefit ratio with respect to the public services and facilities. Protecting and enhancing the environmental quality of new single and multifamily development projects was a cornerstone of the rationale for adoption of the growth management approach. The results of the test indicate projects in the control cities were of comparable environmental quality to those in Petaluma. The third goal set by Petaluma as the city embarked on its growth management program was the provision of 8 to 12 percent annually of new housing stock at a cost which was affordable to the city's low and moderate income citizens. The results of the study indicate the Residential Development Control System, which is used to implement the city's new planning scheme is ineffective in achieving this goal. The point allocation system rewards additional amenities with higher points and actually works against developments designed for low and moderate income families. Petaluma's plan requires all development proposals to be reviewed at the same time, so the volume of business in the planning department becomes feverish as the time for review and evaluation approaches. Has the impact of the new review schedule caused the city of Petaluma to increase the size of its planning staff? The test results indicate each city had different size planning staffs in relation to their population size and they continue to be as they were. It was found that adopting growth management planning, per se, could not be directly associated with the political fortunes of the city's elected officals. However, when the issue remained local, the effect divided voters into camps for and against the issue. When the city attracted national attention, the local voters rallied behind their officials and their plan. The final goal set by the city was to balance new growth in the city so all three sectors shared in the development of the city. Analysis of the study data reveals that this goal was achieved extremely well. Goals set for each of the three sectors were within two percentage points of being right on target. In summary, it appears that growth management planning policies are effective in achieving allocation goals, but are not as capable of achieving economic goals.Item Recombination-associated recovery from 4-nitroquinoline-1-oxide lesions by Bacillus subtilis(Texas Tech University, 1974-05) Laumbach, Andrew DeitliefNot availableItem Structural Insights into Sporulation in Bacillus sibtilis(2010-05-14) Lee, James; Gardner, Kevin H.PAS domains are modular domains that providing specific interaction surfaces for a diverse array of ligands, from small organic compounds to intra and intermolecular protein domains. As such, they are ubiquitous throughout signal transduction pathways in all three kingdoms of life: Bacteria, Archae, and Eucarya (Huang, Edery et al. 1993). The significant role played by PAS domains in Bacillus subtilis sporulation is underscored by the finding that the PAS-A domain is necessary for efficient phosphorylation in the sporulation kinase, KinA(Wang, Fabret et al. 2001). This activity is necessary for initiating a phosphorelay that results in the upregulation of genes required for sporulation. In KinA, dimerization is necessary for individual monomers of the histidine kinase domain to transphosphorylate partner subunits. The dimerization of KinA involves interactions in the PAS-A domain, but molecular details regarding PAS-A dimerization and its importance to KinA activity has not been previous characterized. To investigate these interactions within the context of the KinA homodimer, we expressed the N-terminal PAS-A domain and solved the X-ray crystal structure. Conformational variability was implicated through the observation of different orientations of the dimerization interface in two distinct structural models found in the asymmetric unit of the crystal lattice. These models were used to identify key interfacial residues and the roles of these were tested in a variety of ways by site-directed mutagenesis.Item The impacts on broiler performance and yield by removing antibiotic growth promoters and an evaluation of potential alternatives(2009-05-15) Bray, Joey LynnThree experiments were conducted to evaluate the impacts of removing antibiotic growth promoters (AGP) on broiler performance and yield and to evaluate alternative products as potential replacements. In experiment one, approximately 552,000 broilers were reared in four solid-wall, tunnel ventilated houses that were divided into two paired-house facilities, each assigned one of two dietary treatments. The treated group received basal diets containing salinomycin (SAL), roxarsone (ROX) and AGP, while the control group received the same diets without ROX and AGP. Removal of ROX and AGP had no affect on average body weight and feed efficiency, while livability was significantly affected negatively by the removal of ROX and AGP. Tender, wing, drum and percentage of total white meat showed significant improvements in yield during the study, while all other parts were not affected by removal of ROX and AGP. In experiment two, an investigation was conducted to evaluate the effects on performance from feeding Bacillus subtilis spores (Gallipro?, Chr Hansen A/S, Denmark), as a direct-fed microbial additive, to commercial broiler chickens. Birds were divided among two paired-house facilities. The treatment group received basal diets supplemented with B. subtilis spores, while the control group was fed the same basal diets containing an AGP. Feed conversion ratio was significantly lower for the treatment group, while average body weight, coccidiosis lesion scores, and footpad scores were not affected by the treatments. In experiment three, 6,000 broiler chickens were equally divided among four treatment groups and reared to 49 d to determine the effectiveness mannan oligosaccharides (MOS, Bio-Mos?, Alltech, Nicholasville, Kentucky, USA) as an alternative for an AGP program and MOS plus Natustat? (NAT, Alltech, Nicholasville, Kentucky, USA) as an alternative to an enteric health program (AGP+anticoccidial drug). Average body weight for the control (CON) and antibiotic (ANT) groups was significantly different from the MOS+NAT group, but not the MOS group. Carcass front half, carcass hind half, frame and skin yields were improved for all treatments when compared to the MOS+NAT group. Conversely, percent total white meat yield was improved with the inclusion of MOS when compared to the ANT group. The findings of this research suggest that the removal of AGP from the diets of commercial broiler chickens does not affect the performance and yield of the birds over a one year production period. Furthermore, B. subtilis spores and mannan oligosaccharides provide acceptable alternatives to an AGP program.Item The interaction of 4-nitroquinoline 1-oxide with Bacillus subtilis deoxyribonucleic acid(Texas Tech University, 1970-12) Laumbach, Andrew DeitliefNot availableItem The protection of recombinationless Bacillus subtilis from four-nitroquinoline-one-oxide treatment by infection with bacteriophage PBS-1(Texas Tech University, 1970-12) Strong, James EvansNot availableItem The Relationship of Autolytic and Proteolytic Enzymes to the Development of Competence in Bacillus Subtilis 168 IND(Texas Tech University, 1972-08) Filleman, Jerry WynnNot Available.Item The role of proteolytic enzymes in the regulation of competence development in Bacillus subtilis(Texas Tech University, 1971-05) Ribble, Rodney JayNot available