Floristic quality assessment and ecosystem analysis of the Duncan Bay nature Preserve, Cheboygan County, Michigan

Field Botany of Northern MichiganHere we provide a comprehensive list of flora found within the Duncan Bay Nature Preserve, for which we report a Native Floristic Quality Index number of 69.3. Furthermore, we provide recommendations for site management including a geolocated list of alien and invasive species with potential removal suggestions, details of a geolocated population of Michigan’s threatened state wildflower Iris lacustris, a detailed walking-trail plan including a proposed parking lot location, and informational signs at key locations.http://deepblue.lib.umich.edu/bitstream/2027.42/116389/1/Buchanan_Coy_Ho_Jones_Marshall_McGuffie_Skrzypek_Zettell_2015.pd

A survey of the Formicidae (Insecta) of Wilderness State Park.

InsectsWe surveyed Wilderness State Park over the course of the 2015 summer session, making 4 trips to the park. Formicidae (ants) were surveyed using pit traps, bait traps, leaf litter sampling, and individual collecting. Using a combination of records from this survey and historical records we recorded 40 species of Formicidae. Ant species showed distinct (and previously documented) habitat specializations, with groups of species almost completely confined to either open or wooded habitats. Our sampling demonstrated that multiple collecting techniques are necessary for a complete survey of ant species, but that pit traps provide the bulk of the records in our area. We recorded several county records. Adding these results to those from the previous 4 summers, the Biology of Insect classes have now recorded 305 species in 28 families from Wilderness State Park.http://deepblue.lib.umich.edu/bitstream/2027.42/117509/1/Gallagher_Jones_Landgraf_McGuffie_O'Neil_Regan_Younan_2015.pd

Shape-Dependent Biomimetic Inhibition of Enzyme by Nanoparticles and Their Antibacterial Activity

Enzyme inhibitors are ubiquitous in all living systems, and their biological inhibitory activity is strongly dependent on their molecular shape. Here, we show that small zinc oxide nanoparticles (ZnO NPs)pyramids, plates, and spherespossess the ability to inhibit activity of a typical enzyme β-galactosidase (GAL) in a biomimetic fashion. Enzyme inhibition by ZnO NPs is reversible and follows classical Michaelis–Menten kinetics with parameters strongly dependent on their geometry. Diverse spectroscopic, biochemical, and computational experimental data indicate that association of GAL with specific ZnO NP geometries interferes with conformational reorganization of the enzyme necessary for its catalytic activity. The strongest inhibition was observed for ZnO nanopyramids and compares favorably to that of the best natural GAL inhibitors while being resistant to proteases. Besides the fundamental significance of this biomimetic function of anisotropic NPs, their capacity to serve as degradation-resistant enzyme inhibitors is technologically attractive and is substantiated by strong shape-specific antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), endemic for most hospitals in the world

Atomic Resolution Insights into Curli Fiber Biogenesis

Bacteria produce functional amyloid fibers called curli in a controlled, noncytotoxic manner. These extracellular fimbriae enable biofilm formation and promote pathogenicity. Understanding curli biogenesis is important for appreciating microbial lifestyles and will offer clues as to how disease-associated human amyloid formation might be ameliorated. Proteins encoded by the curli specific genes (csgA-G) are required for curli production. We have determined the structure of CsgC and derived the first structural model of the outer-membrane subunit translocator CsgG. Unexpectedly, CsgC is related to the N-terminal domain of DsbD, both in structure and oxido-reductase capability. Furthermore, we show that CsgG belongs to the nascent class of helical outer-membrane macromolecular exporters. A cysteine in a CsgG transmembrane helix is a potential target of CsgC, and mutation of this residue influences curli assembly. Our study provides the first high-resolution structural insights into curli biogenesis