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Respiratory chain of alkalophilic bacteria. Annual progress report, June 15, 1981-May 15, 1982

Description: In view of the increased energy cost of life at extremely alkaline pH, the extraordinary qualitative and quantitative array of respiratory chain components of alkalophilic bacteria, and the normal growth yields and O/sub 2/ consumption rates of such organisms, it has been proposed that the obligately alkalophilic bacteria possess structural/functional properties of the respiratory chain such that particularly efficient energy conservation is facilitated. The respiratory chain components of Bacillus alcalophilus have been studied in comparison with its non-alkalophilic mutant derivative; a similar study of Bacillus firmus RAB and non-alkalophilic RABN is now partially completed. The alkalophiles contain high quantities of many distinct redox carriers as compared to their derivative and other non-alkalophiles. Determinations of H/sup +/7O ratios are now in progress. A system for study of the regulation of cytochrome expression, as a function of pH, has been developed. Failure of obligate alkalophiles to grow at pH 7.0 now appears to relate to the low membrane potentials produced by respiration at that pH, rather than a failure of pH homeostasis. Since alkalophilic cells are found to be viable at pH 7.0, incubations can be conducted for study of functional and regulatory aspects of respiration.
Date: January 1, 1982
Creator: Krulwich, T.A.
Partner: UNT Libraries Government Documents Department

Ames test results on shot-tank residues

Description: In August 1987, a routine Ames test on soot from the Lawrence Livermore National Laboratory (LLNL) 4-in. gun showed that the soot was mutagenic to Salmonella bacteria. Subsequent liquid chromatography on the soot showed that, out of hundreds of ultravoilet-absorbing compounds found in the residue, only three or four were mutagenic. When a sample large enough to weigh was collected, it was found that No environmentally identified complex mixture has ever been reported with as much Ames/Salmonella activity per gram as the gun residues.'' Since then, Ames tests of hundreds of samples have verified that the residues from our gun tanks may be hazardous to health. The actual degree of the hazard and the identity of the offending chemicals are still unknown. 2 refs.
Date: September 21, 1990
Creator: Bloom, G.H.
Partner: UNT Libraries Government Documents Department

Rapid microbial identification by circular intensity differential scattering

Description: Circular Intensity Differential Scattering (CIDS) is one of the few really new approaches to microbial identification to have come into existence in the past several decades. The CIDS spectra can be measured as a function of wavelength, scattering angle, and/or matrix element, and a number of matrix elements can be measured virtually simultaneously. This panoply of measurements potentially gives the method resolving power for microbial identification. Some representative data taken over the past couple of years on CIDS spectra of several anti-viral vaccines is presented. 17 references; 9 figures.
Date: June 1, 1984
Creator: Gregg, C.T. & Salzman, G.C.
Partner: UNT Libraries Government Documents Department

Characterization of a 1,4-. beta. -D-glucan synthase from Dictyostelium discoideum

Description: Various aspects of research concerning Dictyostelium discoideum are presented. The initial focus of this project was upon: the characterization of potential probes for the cellulose synthase (antibody and nucleic acid), the determination of the cultural induction conditions of cellulose synthesis, the solubilization of the enzyme activity, the development of a non-inhibitory disruption buffer, the generation and isolation of mutant strains deficient in cellulose synthesis, and the development of the capability to determine the degree of polymerization of the in vitro product. I have briefly summarized our most significant findings with only selected data sets being shown in this report in the interest of brevity.
Date: January 15, 1992
Creator: Blanton, R.L.
Partner: UNT Libraries Government Documents Department

First description of a variant of E. coli lacking superoxide dismutase activity yet able to grow efficiently on minimal, oxygenated medium

Description: A strain of E. coli has been obtained which is completely lacking in superoxide dismutase activity and is able to grow efficiently on glucose minimal media being sparged with pure oxygen. While its genotype is unknown, it appears to have arisen from mutation (s) which complements the absence of sodAB gene products without introducing superoxide dismutase activity. 1 ref., 2 figs.
Date: January 1, 1987
Creator: Fee, J.A.; Niederhoffer, E.C. & Naranjo, C.
Partner: UNT Libraries Government Documents Department

Raman activity in synchronously dividing bacteria

Description: Using a spectrometer equipped with an optical-multichannel analyzer as the detector (OMA), we have observed the Stokes laser-Raman spectra of metabolically active Escherichia coli and Bacillus megaterium from 100 - 2100 cm/sup -1/. After lengthy investigation, no Raman lines attributable to the metabolic process nor the cells themselves were found. Previous Raman spectra of active bacteria cannot be used to support nonlinear theories in biology. 34 refs., 9 figs.
Date: January 1, 1985
Creator: Layne, S.P.
Partner: UNT Libraries Government Documents Department

Mechanisms of recombination and function of DNA in bacteria. Progress report, August 12, 1978-August 15, 1979

Description: Most work in the current period centered on the organization and transfer of two classes of drug-resistance determinants in pneumonococcus: (a) insertions of foreign DNA in the chromosome; and (b) plasmid carried genes. Major findings are: determinants for chloramphenicol and tetracycline resistance in some clinical isolates of pneumococcus are present as adjacent insertions of heterologous DNA into the normal chromosome. They are not carried on plasmids as are similar determinants in many species; pneumonococcus will support the growth of resistance plasmids from other streptococci, and these can be transformed into pneumococcus from lysates of S. faecalis (group D) or group B streptococcus; one of the plasmids that has been transformed into pneumococcus mediates a form of DNAse-resistant conjugal transfer among other streptococcal groups and also in pneumococcus. (PCS)
Date: January 1, 1979
Creator: Guild, W.R.
Partner: UNT Libraries Government Documents Department

Atomic force microscopy images of T4 bacteriophages on silicon substrates

Description: A new atomic force microscope incorporating microfabricated cantilevers and employing laser beam deflection for force detection has been constructed and is being applied to studied of biological material. In this study, T4 bacteriophage virus particles were deposited from solution onto electronic grade flat silicon wafers and imaged in air with the microscope. Microliter droplets of the solution were deposited and either allowed to dry or removed with blotting paper. The images show both isolated viruses and aggregates of various sizes. The external structure as well as strands believed to be DNA streaming out of the virus could be observed. The construction of the microscope and its performance are also described. 19 refs., 4 figs.
Date: August 1, 1991
Creator: Kolbe, W.F.; Ogletree, D.F. & Salmeron, M.B.
Partner: UNT Libraries Government Documents Department

Characterization of defective interfering RNAs associated with RNA plant viruses

Description: Our lab was the first to describe and characterize a defective interfering RNA (DI RNAs or DIs) in association with a small RNA plant virus. The features of the DIs that we discovered in infections of tomato bushy stunt virus were compatible with the properties of DIs identified in many animal virus infections. Animal virologists have generally recognized the importance of studying DIs because they are invaluable tools for identifying cis-acting sequences important in virus multiplication and because they offer the opportunity to elucidate mechanisms involved in viral persistence and disease attenuation. Hence our discovery offered a comparably valuable tool for use in plant virus studies for the first time. Since the original observation with TBSV, we discovered the second example of plant viral DI RNAs associated with turnip crinkle virus (TCV), and many other reports have now appeared characterizing DI and DI-like RNAs in other plant viral infections. We are seeking to improve our understanding of the mechanisms of DI generation and the precise nature of the RNA sequences necessary for DI replication and encapsidation. We also want to address the nature of the DI mediated symptom attenuation and interference effects in plants, and to determine the feasibility of using transgenic plants constitutively expressing DI RNAs for disease control. The progress made on each of these objectives is summarized along with the proposed experiments for the continuation period.
Date: January 1, 1993
Creator: Morris, T.J. (Nebraska Univ., Lincoln, NE (United States). School of Biological Sciences) & Jackson, A.O. (California Univ., Berkeley, CA (United States). Dept. of Plant Pathology)
Partner: UNT Libraries Government Documents Department

Instrument for virus identification by polarized light scattering: a preliminary report

Description: An instrument for the identification of biological macromolecules is described. The basis for the instrument is the measurement of circular intensity differential scattering, used as one element of a Mueller matrix. 5 references, 5 figures. (ACR)
Date: January 1, 1984
Creator: Salzman, G.C. & Gregg, C.T.
Partner: UNT Libraries Government Documents Department

Multiparameter light scattering for rapid virus identification

Description: An instrument for making multiparameter light scattering (MLS) measurements from viral suspensions has been described. Calibration methods and a technique for the correction of artifacts were also presented. This measurement technique may have broad applications in cell biology in general and in virology in particular. It may be possible to use MLS to identify viruses directly from clinical specimens. 8 references, 7 figures.
Date: January 1, 1984
Creator: Salzman, G.C.; Grace, W.K.; McGregor, D.M. & Gregg, C.T.
Partner: UNT Libraries Government Documents Department

Enzymology of biological nitrogen fixation

Description: Two genes involved in the regulation of nitrogenase activity, draT and draG, were cloned and found to be contiguous on the Azospirillum brasilense chromosome. The nifH gene, encoding dinitrogenase reductase, is near to draT with an intervening gap of 1.9 kb. The organization of these genes in Azospirillum lipoferum and Rhodosprillum rubrum is similar, but nifH and draT are separated by only 400 bp in the organisms. A. brasilense draTG is very similar to draTG in R. rubrum with 91.8% similarity and 85.3% identity at the amino acid level. Apparently A. brasilense uses the normal ATG initiation codon for draT, and draG. The genes for A. brasilense were able to restore function to appropriate mutants of R. rubrum. The heterologous expression of A. brasilense draTG in R. rubrum was not fully normal, as it responded more slowly to darkness and more quickly to ammonia than wild type cells. Our mutational analysis of the draTG region of A. brasilense confirms the function of these genes in the regulation of nitrogenase activity, but it also revealed minor but demonstrable differences in the control systems of R. rubrum and A. brasilense.
Date: January 1, 1992
Creator: Burris, R.H.
Partner: UNT Libraries Government Documents Department

Anaerobic bioprocessing of low-rank coals. [Veillonella alcalescens and Propionibacterium acidipropionici]

Description: The overall goal of this project is to find biological methods to remove carboxylic functionalities from low-rank coals under ambient conditions and to assess the properties of these modified coals towards coal liquefaction. The main objectives of this quarter were: (1) continuation of microbial consortia development, (2) evaluation of the isolated organisms for decarboxylation, (3) selection of best performing culture (known cultures vs. new isolates), and (4) coal decarboxylation using activated carbon as blanks. The project began on September 12, 1990.
Date: January 30, 1992
Creator: Jain, M.K.; Narayan, R. & Han, O.
Partner: UNT Libraries Government Documents Department

The effects of moderate coal cleaning on the microbial removal of organic sulfur. [Rhodococcuc rhodochrous]

Description: The purpose of this project is to investigate the possibilities of developing an integrated physical/chemical/microbial process for the precombustion removal of sulfur from coal. An effective pre- combustion coal desulfurization process should ideally be capable of removing both organic and inorganic sulfur. A variety of techniques exist for the removal of inorganic sulfur from coal, but there is currently no cost-effective method for the pre-combustion removal of organic sulfur. Recent developments have demonstrated that microorganisms are capable of specifically cleaving carbon-sulfur bonds and removing substantial amounts of organic sulfur from coal. However, lengthy treatment times are required. Moreover, the removal of organic sulfur form coal by microorganisms is hampered by the fact that, as a solid substrate, it is difficult to bring microorganisms in contact with the entirety of a coal sample. This study will examine the suitability of physically/chemically treated coal sample for subsequent biodesulfurization. Physical/chemical processes primarily designed for the removal of pyritic sulfur may also cause substantial increases in the porosity and surface area of the coal which may facilitate the subsequent removal of organic sulfur by microoganisms. During the current quarter, coal samples that have been chemically pretreated with methanol, ammonia, and isopropanol were examined for the removal of organic sulfur by the microbial culture IGTS8, an assay for the presence of protein in coal samples was developed, and a laboratory-scale device for the explosive comminution of coal was designed and constructed.
Date: January 1, 1991
Creator: Srivastava, V.J.
Partner: UNT Libraries Government Documents Department

Enzymology of acetone-butanol-isopropanol formation

Description: The long-term goal of the project is to understand the fundamental properties of biological solvent production. Our approach is to elucidate first the molecular properties of solvent-producing enzymes and then to apply to information gained from the enzymological study to investigate control mechanisms for the solvent-producing pathways and the expression of solvent-production genes. Our research primarily involves two strains of Clostridium beijerinckii: C. Beijerinckii NRRL B593 which produces isopropanol in addition to acetone, butanol, and ethanol, and C. beijerinckii NRRL B592 which produces acetone, butanol and ethanol, but not isopropanol. In more recent studies, we also included another solvent-producing organism, Bacillus macerans. Objectives for the reporting period were: to characterize the distinct types of alcohol dehydrogenase; to purify and characterize acetoacetyl-CoA-reacting enzymes; and to clone and sequence the gene encoding the primary/secondary alcohol dehydrogenase of C beijerinckii NRRL B593 and to search for the promoter region for solvent-production genes.
Date: January 1, 1992
Creator: Chen, Jiann-Shin.
Partner: UNT Libraries Government Documents Department

Isolation of legionnaires' disease bacteria from non-epidemic related habitats

Description: Continuous centrifugation of large volumes of water from natural southeastern lakes allowed quantitative screening for Legionnaires' disease bacteria (LDB) by direct immunofluorescent staining. Presumptively positive samples were injected intraperitoneally into guinea pigs and the LDB were isolated and identified by their morphological, cultural, physiological, and serological characteristics.
Date: January 1, 1979
Creator: Fliermans, C.B.; Cherry, W.B.; Orrison, L.H. & Thacker, L.
Partner: UNT Libraries Government Documents Department

Legionnaires' Disease Bacterium in power-plant cooling systems: Phase 1. Final report

Description: A survey was undertaken of the distribution, density, viability, and infectivity of Legionnaires' Disease Bacteria (Legionella) in power plant cooling systems. Water samples were collected during each of the four seasons at various locations within each of nine power plants and from ambient waters at each site. Measurements of a number of physical and chemical characteristics were made, and Legionella profiles (density, viability, and infectivity for guinea pigs) were obtained. Legionella were detected in nearly all samples. Water from closed-cycle cooling systems frequently had lower densities of Legionella than the ambient water. Nonetheless, infectious Legionella, as defined by their isolation from inoculated guinea pigs, were significantly more likely to be found in samples from the plant-exposed water of closed-cycle plants than in samples from once-through plants or in ambient samples. A new species (L. oakridgensis) was initially isolated from two of the sites, and it has since been found to have a widespread distribution. Two other organisms found to cause illness in guinea pigs may also be new species. Phase II of the project involves investigating possible cause/effect relationships between physicochemical variables and Legionella. This work may contribute toward eventual control techniques for this pathogen.
Date: June 1, 1983
Creator: Christensen, S.W.; Solomon, J.A.; Gough, S.B.; Tyndall, R.L. & Fliermans, C.B.
Partner: UNT Libraries Government Documents Department

Bench-scale co-oxidative production of propylene oxide by methanotrophs

Description: The feasibility of the co-oxidative production of value-added chemicals using methanotrophs has been investigated by the authors. Several of these co-oxidative products have been evaluated for stereo- or regiospecific properties. Propylene oxide (1,2-epoxypropane) is one of the products that has been selected for further evaluation. This paper describes the first steps toward bench-scale production of propylene oxide. Propylene oxide has been produced stereospecifically (60% R-form, 40% S-form) in gram quantities in bench-scale liquid culture reactors. Several operational parameters and conditions have been determined for both a continuous stirred-tank reactor (CSTR) and a packed-bed bubble-column reactor (PBR). The production phase of the propylene oxide has been significantly extended by intermittent addition of propylene and regeneration with methane. The paper also describes the performance of the CSTR and PBR for propylene oxide production.
Date: January 1, 1990
Creator: Hill, A.H.; Kelley, R.L.; Srivastava, V.J.; Akin, C.A. (Institute of Gas Technology, Chicago, IL (United States)); Hayes, T.D. & Frank, J.R. (Gas Research Inst., Chicago, IL (United States))
Partner: UNT Libraries Government Documents Department

Stereospecificity and physiology of co-oxidative production of chemicals by methanotrophic bacteria. [Methane monooxygenase:a2]

Description: Methanotrophic bacteria can use methane as a sole source of carbon and energy. The enzyme responsible for the oxidation of methane in these organisms, methane monooxygenase, is also able to biotransform a number of substrates into industrially important chemicals. One such example is the oxidation of propylene to propylene oxide. Several strains of mesophilic and thermophilic methanotrophs have been tested for their ability to produce propylene oxide with formate, methanol, and methane as the co-oxidative substrates. Cultures in the late stationary phase were found to be more productive than exponentially growing cultures. Methane did not inhibit propylene epoxidation on low-density cultures; in fact, the yields of propylene oxide were greater when both methane and propylene were present than when only propylene was present. In higher-density cultures, however, methane did appear to inhibit oxidation of propylene. The effects of several culture parameters such as pH, temperature, and concentration of micronutrients on propylene oxide production ad steroespecificity were determined. Propylene oxide production was proportional to the amount of cell loading up to 14 g/L. Unwashed cells produced more propylene oxide than washed cells. The long- and short-term inhibitory effects of propylene oxide on the methanotrophic strains were also investigated. A tolerance of up to 1 M propylene oxide was observed, and the maximum inhibitory effect was seen within 30 minute. The steroespecificity for propylene oxide production and oxidation of 3-methylcyclohexene was determined for several strains. Methylosinus trichosporium (OB3b), particularly a cell-free extract of this strain, had the greatest steroespecificity. 13 refs., 12 figs., 3 tabs.
Date: January 1, 1991
Creator: Kelley, R.L.; Hoefer, D.E.; Conrad, J.R.; Srivastava, V.J. & Akin, C.
Partner: UNT Libraries Government Documents Department

(Physiology and genetics of metabolic flux control in Zymomonas mobilis)

Description: The funded research deals with the physiology and genetics of glycolytic flux control in Zymomonas mobilis. Two fundamental biological questions are begin addressed: First, how do the enzymes of glycolytic pathways act in concert to regulate metabolic flux Second, what is the role of gene expression in regulating high level synthesis of the glycolytic enzymes in a balance that allows proper glycolytic flux control The specific objectives of the grant are as follows: 1. To clone the structural and regulatory regions of the Z. mobilis genes encoding glucose-6-phosphate dehydrogenase, phosphoglucose isomerase, enolase, 6-phosphogluconate dehydratase, 2- keto-3-deoxy- 6-phosphogluconate aldolase, glucokinase and fructokinase. 2. To characterize the structure of these genes with respect to nucleotide sequence, transcriptional initiation sites promoter location, evolutionary relatedness to similar genes from other organisms, and organization of these genes on the genome. 3. To investigate the effects of genetically engineered alterations in the levels of the cloned enzymes on metabolic flux and cell growth. 4. To study transcriptional and post-transcriptional regulation of the genes encoding the enzymes of the Entner-Doudoroff pathway. The first two specific objectives have now been fully completed. Significant progress has been made on the fourth objective and work on the third objective is well underway.
Date: January 1, 1992
Creator: Conway, T.
Partner: UNT Libraries Government Documents Department