Stadler Genetics Symposia, volume 12, 1980 (MU)

Permanent URI for this collection

https://hdl.handle.net/10355/66510

Contents of volume 12

Acknowledgments
Contents
Participants
E. R. Sears Scholarship Fund
Monica Riley: EVOLUTION OF THE BACTERIAL GENOME
Judith H. Miles: MEDICAL GENETICS: IMPACT AND STRATEGY
Jeffrey C. Hall, Richard W. Siegel, Laurie Tompkins and C. P. Kyriacou: NEUROGENETICS OF COURTSHIP IN DROSOPHILA
Takeo Maruyama and Eiichi Soeda: MOLECULAR EVOLUTION IN PAPOVA VIRUSES AND THEIR HOST SPECIES, AND IN BACTERIOPHAGES
Charles M. Radding, Chanchal Das Gupta, Takehiko Shibata and Richard P. Cunningham: THE TOPOLOGY OF HOMOLOGOUS PAIRING
Judy D. Wall: NITROGEN FIXATION BY PHOTOSYNTHETIC BACTERIA
T. O. Diener: VIROIDS: MINIMAL GENETIC SYSTEMS
G. Nigel Godson: EVOLUTION OF DNA SEQUENCE: MECHANISMS AND MODELS AS SEEN IN SMALL PHAGES
Maurice Green, William S. M. Wold, Karl H. Brackmann, Takumi Matsuo, Shuichi Hashimoto and Janey Symington: THE INTEGRATION AND EXPRESSION OF HUMAN DNA TUMOR VIRUS GENES
Cumulative Contents of the Proceedings of the Stadler Genetics Symposia

Browse

Now showing 1 - 5 of 10

Stadler Genetics Symposia, volume 12, 1980 : Preliminaries and back matter
(University of Missouri, Agricultural Experiment Station, 1980) Stadler Genetics Symposium (12th : 1980 : Columbia, Missouri)
Nitrogen fixation by photosynthetic bacteria : (Rhodospirilum rubrum, Rhodopseudomonas capsulata, glutamine ,nitrogenase)
(University of Missouri, Agricultural Experiment Station, 1980) Wall, Judy D.; Stadler Genetics Symposium (12th : 1980 : Columbia, Missouri)
Biological nitrogen fixation is not only essential for world nitrogen balance but it is also an alternative to expensive commercial fertilizer for crop production. To achieve the maximum utilization of this natural process, an understanding of the mechanism of N[subscript 2] reduction and its regulation is being sought. The photosynthetic bacteria, in particular members of the Rhodospirillaceae, are attractive organisms for genetic and biochemical analyses of nitrogen fixation. Characterization of mutants of these bacteria derepressed for synthesis of the nitrogenase complex in the presence of ammonium salts supports a critical role for glutamine and [lowercase alpha]-ketoglutarate in the regulation of synthesis. In addition, a mechanism exists for activity control by covalent modification of one of the protein components of the complex. The signal for modification and the extent to which this control mechanism occurs in other diazotrophs are under investigation.
Evolution of the bacterial genome : (bacterial DNA evolution, vertical vs. horizontal evolution)
(University of Missouri, Agricultural Experiment Station, 1980) Riley, Monica; Stadler Genetics Symposium (12th : 1980 : Columbia, Missouri)
Not all parts of bacterial genomes have evolved at the same rate. Among related genomes, some gene segments are highly conserved, some are less conserved and some are highly variable. We have studied the relatedness of selected gene segments in the genomes of a group of E. coli strains and other enteric bacteria, using E. coli K12 DNA as a reference standard. We found variation in the degree of relatedness among the gene regions sampled, implying that evolutionary rates varied in different parts of enteric genomes and/or that different mechanisms of evolution have predominated in different gene regions, Mechanisms of evolution of the bacterial genome are discussed. These can be grouped as those mechanisms that are vertical in character, and those that are horizontal in character. Criteria are suggested that may help to identify genes whose inheritance has been primarily horizontal rather than vertical. Arguments are given that neither internal genome rearrangement nor promiscuous exchange of genes among the chromosomes of dissimilar bacteria have played dominant roles during evolution of the bacterial genome.
The topology of homologous pairing : (genetic recombination, RecA protein, strand crossover, joint molecules, heteroduplex joints, branch migration)
(University of Missouri, Agricultural Experiment Station, 1980) Radding, Charles M.; Das Gupta, Chanchal; Shibata, Takehiko; Cunningham, Richard P.; Stadler Genetics Symposium (12th : 1980 : Columbia, Missouri)
The RecA protein, which is essential for genetic recombination of E. coli , promotes homologous pairing in vitro. Studies of purified RecA protein have shown that it promotes the homologous pairing of a number of topological variants of DNA including : a) complementary linear single strands, b) linear single strands and duplex DNA, c) circular single strands and either linear duplex DNA, or nicked circular duplex DNA, and d) duplex DNA with a gap in one strand and closed circular duplex DNA. According to these observations RecA protein will form stable joint molecules if one molecule is single-stranded or partially single-stranded and if either molecule has a free end. Circular single strands, as well as linear ones, also stimulate RecA protein to unwind duplex DNA. These observations, which reveal a lack of specificity with regard to ends, suggest that RecA protein promotes homologous pairing of strands in a side-by-side fashion, and that free ends subsequently serve to stabilize the product by permitting the formation of heteroduplex regions with the normal right-handed helical structure.
Medical genetics : impact and strategy : (genetic disease, birth defects, prenatal diagnosis)
(University of Missouri, Agricultural Experiment Station, 1980) Miles, Judith H.; Stadler Genetics Symposium (12th : 1980 : Columbia, Missouri)
Genetic diseases and birth defects have a major impact on all levels of health care because of their enormous consequences for the individual and family and because of the high frequency of occurrence. That over 3000 described disorders due to either chromosome aberrations, to single-gene mutations or to many genes acting together and with the environment have been described illustrates the diversity in these diseases. The concern of the medical geneticist is to establish an accurate etiologic diagnosis, to counsel patients and families concerning their risks of occurrence or recurrence and to devise and provide methods of preventing both the effects and ultimately the occurrence of genetic diseases.

Browse

Recent Submissions