We are developing new classes of compounds as biochemical tools, enzyme probes, and as potential antiviral, antitumor, and biocidal medicinal agents. We have developed new methodologies for the functionalization of heterocycles and for the synthesis of nucleosides. The classes of compounds investigated are selected to advance certain select biomedical research areas like cancer and infectious diseases. The majority of the Groziak Lab research efforts are focused on practicing the art of heterocycle and nucleoside analog design, synthesis, and characterization.
Our group focuses on the development of nucleic acid aptamer--‐based imaging agents for small biological molecules such as steroids and coenzymes, which have been shown to play important roles including in cellular protective mechanisms and serving as disease markers. The ability to carry out selective imaging will provide useful insights into their involvement in various processes and in turn, the study of novel or more efficacious therapeutic strategies for diseases. Through an in vitro evolutionary process, we can obtain oligonucleotides with high binding affinity for the desired targets. The chemical versatility of these nucleic acid strands will allow for relatively simple conjugation to a fluorescence or magnetic resonance imaging fragment.
My research interests involve the development and application of quantum mechanical models for the behavior of molecules, solids, and interfaces. One area focuses on the f-block lanthanide and actinide elements, whose increasing importance in technological applications is accompanied by concerns over the environmental impacts of their production and disposal. We are employing first-principles electronic structure techniques to characterize bonding in f-element complexes and materials. The motivation is the development of new chemical insights that will enable the sustainable and safe processing of f-element compounds. A second area is the study of interfaces formed between a solid oxide and liquid water using first-principles molecular dynamics simulations. As many important catalytic and environmental processes take place at oxide/water interfaces, we seek a fundamental understanding of the relationship between oxide surface structure, water ordering, and chemical reactivity. For more information, see profile page here.
My research program involves investigating various aspects of environmental organic contamination. The major research focus is the study of the interaction of these environmental contaminants with biological systems specifically to understand their impact on human health. My group is working to characterize the metabolic products and pathways of organic pollutants such as flame retardants, antiseptics and condensed thiophenes which have been shown to bioaccumulate in nature. In a related project, we are also studying ways in which these contaminants could be degraded as part of wastewater treatment.
Structural Biophysics, Biophysical Chemistry and Biochemistry Biophysical and biochemical studies on structures of nucleic acids and proteins. Dr. Kim's research interests lie in investigating structures and functions of important macro bio-molecules including nucleic acids and proteins using various biophysical and biochemical techniques. Currently, his research group is working on elucidation of three dimensional structures of small RNA motifs that are important in the RNA replication mechanism of various RNA viruses. They use high-resolution multi- dimensional NMR to investigate the structures of these viral RNAs.
A better understanding of the biochemical mechanisms by which plants tolerate and accumulate toxins in the environment has application in the growing field of phytoremediation, the use of plants to remove, stabilize, or detoxify pollutants. My research group uses molecular biology, biochemistry, and analytical chemistry techniques to understand the differences between metal hyperaccumulating plants and their metal-sensitive relatives. In particular, we study the chemical speciation of metals in plants and key molecular adaptations (differences in gene sequence, mRNA and protein expression, and enzyme activity and structure) that are responsible for differences in metal metabolism and chelation. Our current projects focus on key proteins involved in salinity and boron tolerance in poplar and mercury speciation and localization in plants.
Tony Masiello received bachelor degrees in both Chemistry and Physics from Eastern Washington University. He went on to Oregon State University and received a Masters degree in Physics and a Ph.D. in Physical Chemistry, specializing in non-linear optical spectroscopy. Before coming to the Department of Chemistry and Biochemistry in 2008, Dr. Masiello was a postdoctoral associate at both the Pacific Northwest National Laboratory in Richland, WA, and the National Institute of Standards and Technology in Gaithersburg, MD. At these positions, Dr. Masiello worked on techniques to characterize, detect and quantify trace amounts of atmospheric gases utilizing a variety of spectroscopic methods such as infrared spectroscopy, cavity ringdown spectroscopy and integrated cavity output spectroscopy. His current research focuses on assessing the quantity of greenhouse gas emissions from agricultural and biological processes, as well as determining molecular structural parameters for strained boron and carbon compounds. Dr. Masiello has taught courses in General Chemistry, Physical Chemistry and Environmental Chemistry, and has developed laboratory projects for the chemistry portion of the Bechtel and Broadcom "Foundations in Science" STEM grant.
Our work focuses on analysis of a cluster of Escherichia coli genes which appear to play a role in cell cycle regulation. The analysis involves physiological studies on mutants carrying lesions in the relevant genes, isolation and manipulation of the genes, complementation studies using cloned genes and mutant cells, and attempts to understand the way the genes in the cluster are regulated. RNA measurements have led to the conclusion that several of the genes are co- expressed and more than one promoter may be involved in gene expression. Although some of the genes in the cluster appear to have a role in the cell cycle, the exact functions are unknown. One of the genes, yqgF, has been shown to be essential for E. coli survival. Homologues of this gene are found in other prokaryotes but no related genes or proteins have been identified in eukaryotes. The protein encoded by yqgF therefore fits the profile of a possible target for new types of antibiotics. We are attempting to determine the function of the YqgF protein by studying the effect of mutations that decrease its level of expression on cell function. One current approach involves monitoring the segregation of chromosomes in normal and mutant cells using fluorescence microscopy; another involves testing normal and mutant cells for differences in possible enzymatic activities predicted from bioinformatics studies.
My laboratory focuses on enzymes. These biomolecules are capable to accelerate chemical reactions to impressive speeds under mild conditions and often with tight stereochemical control.
Research students in my laboratory characterize enzymes involved in neurotransmission and detoxification from marine gastropods (mostly Tritonia diomedea). Together we aspire to make a contribution to the field of marine ecology from a biochemical perspective. Marine gastropods show enticing behaviors, including the consumption of toxic food. The characterization of enzymes involved in detoxification or toxin resistance should thus help to unravel the biochemical basis for an animal’s survival strategies. This project is pursued in collaboration with Dr. James Murray (Biology Department, CSU East Bay) and Dr. Taro Amagata (Chemistry Department, SF State).
Another project is dedicated to enzyme immobilization using sol-gel technology. We aim to transform the enzyme chloroperoxidase (CPO) into a re-usable biocatalyst. CPO is one of the most versatile heme proteins known to date and catalyzes peroxidation, sulfoxidation, epoxidation, and halogenation reactions with various substrates. Our criteria for the generation of a re-usable biocatalyst are high catalytic efficiency, excellent enzyme retention and re-usability, and enhanced stability towards harsh reaction conditions (e.g., elevated pH, presence of organic co-solvents). Research students in my laboratory use different spectroscopic techniques (UV/VIS, CD), enzyme activity assays, and porosimetry measurements to characterize their own enzyme-sol-gel hybrid materials.
More information about the Sommerhalter Laboratory can be found on the following web-page: http://www.sci.csueastbay.edu/~msommerhalter/.