DNA four-way junctions (also known as Holliday junctions) are the primary structural intermediate during recombination, an important process responsible for biological evolution and maintenance of genomes. These junctions arise from the assembly of four nucleic acid strands to produce double-helical regions extending from a central point. Although much progress has...
Contact of blood with the surfaces of synthetic materials is associated with spontaneous protein adsorption, initiating platelet aggregation, the coagulation cascade, and the eventual development of a stable clot. Current therapy to inhibit implant-induced thrombosis is life-long administration of systemic anticoagulants. An alternative to the systemic administration of anticoagulant drugs...
The halogen bond is a non-covalent, stabilizing interaction analogous to a hydrogen bond in which an anisotropically polarized halogen atom interacts
electrostatically with a Lewis base. Until very recently, the ability of halogens to form these stabilizing interactions in biological macromolecules was all but unknown, but
examples of halogen bonding...
Cell motility and invasion are important for development, immunity, wound healing, and tumor cell metastasis. Cells on two dimensional substrates migrate in three steps: protrusion of the front end, translocation of the cell body, and retraction of the rear end. For cells to migrate efficiently, these steps need to be...
Pyrenophora tritici-repentis (Ptr) is the fungal causal agent of the disease tan spot in wheat and causes necrosis and chlorosis in infected leaves. These symptoms are caused by host-selective toxins (HSTs), molecules that serve as the sole determinants of pathogenicity. Ptr has three known HSTs, the proteinaceous Ptr ToxA and...
To identify factors limiting 'Candidatus Pelagibacter ubique' maximum cell density and growth rate in pure culture on seawater, the genome sequence of 'Cand. P. ubique' was analyzed, culturing experiments with organic and inorganic nutrient additions were made, and radiotracer uptake experiments were performed. The genome was sequenced, custom data mining...
Oxygen derived radicals are involved in many aspects of life from aging and cell signaling to disease states as diverse as heart disease, diabetes, neurodegeneration and inflammation. Therefore, understanding the function of antioxidant defense proteins and the effects of oxygen derived radicals on protein function is essential to elucidate the...
The structural polymorphic nature of DNA has been long been recognized since the model of the right-handed B-DNA duplex proposed by James Watson and Francis Crick was accepted. Its malleability is thought to be critical in protein recognition and manipulation. In particular, it can form Holliday junctions, four-way DNA structural...
I studied small-mammal communities and their response to grazing in mixed-conifer forests and oak woodlands in the Cascade-Siskiyou National Monument in southern Oregon. My objectives were to (1) compare small-mammal communities among forest types and grazing intensities, (2) identify riparian affiliated species, and (3) describe microhabitat associations. Over two years,...
Live western larch, Larix occidentalis Nutt., a tree species resistant to the Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, produces the monoterpene 3-carene in higher concentrations compared to Douglas-fir, the preferred host of D. pseudotsugae (Reed et al. 1986). The inhibitory effects on attraction to aggregation pheromones and toxicity of 3-carene to...