Assaying the Substrate Activities and Enantioselectivities of Recombinant Flavin-Dependent Monooxygenases toward Aryl Sulfides

College of Natural Resources & Sciences

Certain Flavin Monooxygenases (FMO) are enzymes with the potential to catalyze single-enantiomer oxidation of aryl sulfides to chiral sulfoxides. Aryl sulfoxides have a wide array of pharmaceutical and agricultural applications, but many of these enantiomers have yet to be selectively and efficiently synthesized. The enzymes examined in this study are FMOs from Mus musculus, Xenopus tropicalis, Homo sapiens, and BVMO4 and BVMO24 from Rhodococcus jostii RHA1. The genes were cloned into a vector for expression in Escherichia coli and whole-cell mediated reactions with various aryl sulfides were performed to determine their activity toward the substrates and to determine the enantioselectivity.

Assessing and mitigating metabolic response of HEK293 cells to cytotoxic metals using ascorbic acid

Elizabeth Kowalski, Biological Sciences Undergraduate Student

College of Natural Resources & Sciences

We examined how HEK293 kidney cells responded metabolically to heavy metal poisoning by cadmium chloride (CdCl2), aluminum chloride (AlCl3), and cesium chloride (CsCl) using two fluorometric assays (resazurin and MitoTracker). We then attempted to mitigate adverse effects by treating these cells with ascorbic acid (vitamin C).

Assessing nocturnal habitat selection of small mammals on an urban-rural gradient using camera trapping

College of Natural Resources & Sciences

Urban development forces city and town boundaries to encroach further into wildland habitats and natural landscapes all over the world, causing immense habitat loss and fragmentation. Human-wildlife conflict with mesocarnivores (skunks, foxes, raccoons, etc.) increases as rising rural population densities push more small mammals into anthropogenic areas. This senior thesis study uses trail cameras to assess habitat and resource use vs. availability along the wildland-urban interface among nocturnal small mammals to determine presence of selection.

Assessing Responses of Intertidal Communities to Ocean Acidification and Hypoxia in Northern California

College of Natural Resources & Sciences

During bouts of strong upwelling nearshore areas in northern California can experience extended periods of hypoxic, corrosive waters due to a relatively narrow shelf and poleward shoaling of isother ms. To assess the response of intertidal communities to these conditions we established and surveyed a series of intertidal sites in Humboldt County that vary in the extent of nearshore mixing and are likely to vary in exposure to hypoxia and low pH conditions. We report the results of initial surveys of our sites, including data on sea star wasting disease, and relationships to variation in temperature, salinity, pH and dissolved oxygen.

Astronomy Education Research

College of Natural Resources & Sciences

The basis of our research is to assess why learning gains are low within introductory astronomy courses and how scores can be improved. Examining pre and post scores from an Astronomical Diagnostics Test we were able to examine learning gains of fifty-six students. We used Hake’s normalized gain formula to quantify learning gains. The average learning gain found was 0.20 and the highest gains fell among questions such as phases and position of the moon, eclipses, and seasons on Earth, with gains between 0.5-.64. Because Hake’s normalized gain formula is biased, we are looking into other methods of quantifying our data.

Availability of Perch Structures Correlates with the Abundance and Richness of Raptors in Humboldt County

College of Natural Resources & Sciences

Perches are necessary for raptor species in both their foraging and roosting behavior. The distribution of foraging and roosting raptors is influenced by the availability of perches and prey. However, little is known about the influence of different available perch types, within a habitat, has on raptors. My research aimed to address the question of whether local raptor abundance and richness correlates with the availability of a variety of perch types in a habitat.

Avian Occurrence Data Extraction Using Python Programming

College of Natural Resources & Sciences

Bird detection data helps inform management on how species might be shifting their distributions due to changes in the environment. This project uses a Python program to create a graphical user interface (GUI) that assists in gathering avian species occurrence data from a number of biological information websites such as Biodiversity Information Serving Our Nation (BISON), eBird, and Global Biodiversity Information Facility (GBIF). Data is extracted to contain location coordinates of the detection along with the species name. The final data is exported as a comma separated values (CSV) file into a created desktop folder that can be imported into a geographical information system.

Bacterial expression of G-protein coupled receptor CB2 fusion protein

College of Natural Resources & Sciences

The G-protein coupled receptor (GPCR), CB2, is part of a widespread neuromodulatory system found in all animals and is suspected to play a role in both CNS and immune system functions, yet it is a relatively understudied. We demonstrated a successful method for the expression and purification of the GPCR CB2 protein from BL21(DE3) pLysS competent cells. This method involves the culturing of an E. coli BL21(DE3) pLysS MBP-CB2-6xHis cell line, induction of CB2 receptor expression via IPTG, and the harvest and isolation of expressed CB2 proteins via Ni-NTA Immobilized Metal Affinity Chromatography. This method was proven to be successful based on SDS-page and spectrophotometric analyses.

Baker Cypress Seed Viability in Relation to Cone Age

College of Natural Resources & Sciences

Hesperocyparis bakeri, better known as Baker cypress, is a serotinous species which suffers from low seed viability. Previous research has shown that Baker cypress seed viability begins to decline with cone age and thus the low overall viability of Baker cypress cones is not unexpected (Milich et al., 2012). However, little is known about the cone age at which seed viability begins to decrease. We investigated seed viability in relation to cone age by sampling twenty branches from five Baker cypress trees located in Burney, Shasta County in north-eastern California. Seeds were scarified and placed in a 1% tetrazolium red solution for 18 hours, cut longitudinally to determine viability.

Barn owl nest box selection on a pistachio farm in the Central Valley

College of Natural Resources & Sciences

Overabundant populations of rodents in agricultural areas cost California farmers 5.3% to 8.8% in profits annually. Installing nest boxes to encourage the presence of rodent predators such as barn owls (Tyto alba) is a form of biocontrol that has the potential to limit rodent activity in agricultural settings. Previous works identified the spatial scales of nest box selection on vineyards in Napa and Sonoma Counties which are rather heterogenous agricultural landscapes. Determining at which spatial scale barn owls select nest boxes in the Central Valley can inform how nest boxes should be constructed and where they are best placed to encourage occupancy in homogenous agricultural landscapes.