Research - Microbial Genetics and Development

The Cande Lab researches the mechanism of chromosome segregation during mitosis and meiosis, to understand changes in chromosome structure and behavior that lead to pairing of homologous chromosomes during meiotic prophase and their segregation at Meiosis I and II. We use three model organisms: Giardia intestinalis, Schizosaccharomyces pombe, and Zea mays. We also use a computerized light microscope workstation that records three-dimensional images of multiple cellular components in fixed and living cells.

The Coates Lab focuses on environmental microbiology: applied microbiology and bioremediation. We investigate removal of radioactive toxic metals, carcinogenic petroleum-based hydrocarbon contaminants, and toxic munitions byproducts from the environment. Recently, we identified dominant groups of bacteria that can transform perchlorate wastes into innocuous chloride, isolated and characterized more than 40 such bacteria, and identified the common biochemical pathway and genetic systems involved.

Cell specialization, cell communication and nonself recognition are crucial mechanisms in filamentous fungi. Neurospora crassa's experimental tractability make it a superb system to address microbial communication questions. We study communication and self-signaling mechanisms mediating hyphal fusion, and nonself recognition mechanisms resulting in programmed cell death. We use molecular biology, genetics, cell biology, genomics and bioinformatics to investigate the molecular and cellular basis of nonself recognition during the filamentous fungi lifecycle.

Prokaryotes are highly organized cells with many ultrastructural similarities to eukaryotes. In addition to a highly dynamic cytoskeleton composed of homologues of actin, tubulin and intermediate filaments, many prokaryotes possess intracellular membranous organelles. My lab uses bacterial magnetosomes as a model system to study the molecular mechanisms governing the biogenesis and maintenance of prokaryotic organelles. Using a variety of approaches, we identify and investigate key genes involved in controlling magnetosome formation and function.

Our research group studies aspects of epiphytic bacteria that live on healthy plants' surfaces, emphasizing bacteria active in ice nucleation, causing frost damage to plants. We also study plant pathogenic bacteria that inhabit plant surfaces before infection. We use molecular genetic and ecological approaches to study how epiphytic bacteria interact with other microorganisms on plants, and with the plants on which they live. We seek to better understand adaptations epiphytic bacteria have evolved to exploit this unique habitat.

Photosynthetic organisms have evolved multiple mechanisms to cope with excessive light. We seek to identify and dissect these processes by isolating algal and plant mutants. We use a diverse set of techniques, including genetics, physiology, biochemistry, and molecular biology, focused on one particular species, Chlamydomonas reinhardtii, a unicellular green alga. We study the cellular processes involved in coping with reactive oxygen species produced in excessive light.

We isolate pure populations of Caulobacter swarmer cells and observe many parameters during their synchronous cell cycle progress including fluorescent protein localization, DNA content, and global transcriptional patterns. The sequenced Caulobacter genome expedites genetic manipulations and lets us search comprehensively for genes affecting processes of interest. We also pursue in vitro studies to determine how biochemical properties of individual regulatory proteins contribute to cell cycle progression and cellular asymmetry.

Vitamin B12 is essential to most animals but is synthesized only by certain prokaryotes. Using genetic, biochemical, and bioinformatics approaches, we are investigating three areas related to vitamin B12 in bacteria: 1) the biosynthesis of 5,6-dimethylbenzimidazole (DMB), the least understood component of B12; 2) the function of B12 in the symbiotic interaction between the nitrogen-fixing bacterium Sinorhizobium meliloti and its plant host, alfalfa, and 3) the structure and function of novel B12-like compounds found in nature

We seek to understand the molecular and cellular basis of microbial pathogenesis and the mechanisms used by the host to defend against infection. Specifically, the lab focuses on the interaction of the facultative intracellular bacterial pathogen Listeria monocytogenes and mammalian cells.

We research two facets of development in the fruiting bacterium Myxococcus xanthus. The first concerns cell-cell communication and signal transduction; the second concerns the regulation of gene expression during cellular morphogenesis and development. Myxococcus exhibits complexity of multicellular behavior and morphogenetic development unusual among prokaryotes. We apply sophisticated genetic and molecular biological techniques to examine these processes.