The Faculty

FACULTY

RESEARCH

Jeffrey B. Arterburn, Ph.D.
Chemistry & Biochemistry
505-646-1111
E-mail: jartebu@nmsu.edu
Chemistry Room 293

Research projects in Dr. Arterburn's laboratory have originated from an interest in developing new methodology for organic synthesis, an appreciation for the unique chemistry of transition metal complexes containing metal-ligand multiple bonds, and a desire to synthesize new antiviral drugs and radiopharmaceuticals.

To understand physiological adaptations for flight and high-altitude tolerance in birds, my students and I study temperature regulation, energetics, cardiac and respiratory mechanics, oxygen and carbon-dioxide transport, and body-fluid volume regulation. We also investigate adaptations to hypoxia at the tissue and cell levels, especially in skeletal muscle, eye, and brain.

The laboratory research focuses on two major areas of importance to New Mexico agriculture, plant viruses and a fungal endophyte of locoweed. We are currently characterizing the biology and epidemiology and beet curly top virus which infects chile in New Mexico. Research is ongoing to examine viral strain variation at the molecular level, virus transmission by insects, and host resistance, as well as documentation of the role or weed hosts and vector populations in disease epidemiology. We are also studying the role that a fungal endophyte of locoweed plays in the toxicity of this plant which is poisonous to mammals. We are characterizing the fungus genetically, assessing the toxicity of the fungus in rats, and studying the plant-fungus interactions.

Different organs of the head, for example the nose, eyes and ears, must develop in a regulated manner so that each organ’s size and position is proportional to the whole head and to each other. This tight coordination is mediated by interplay between the “selector genes”, which specify tissue and organ type, and signal transduction pathways, which mediate cell communication to integrate growth and patterning. Remarkably, both the selector genes and the signaling factors are well conserved in all metazoans. I am interested in a basic question in this area, namely, what are the mechanisms that localize expression of selector genes for eye, antenna and other organs of the head with respect to one another, and how is this separation maintained? My approach utilizes the powerful genetic and molecular tools available in the fruit fly Drosophila melanogaster, which make it an ideal system for discovering the genes responsible, and for understanding their relationships to one another. One focus of the lab is to understand how the Drosophila Epidermal Growth Factor Receptor (Egfr) controls the expression of the selector genes for eye and antenna. The other focus in the lab involves two genes called dan and danr, which are required for eye development and able to convert antennal precursors to an eye fate.

Research in our group lies at the interface of organic synthesis, biology, and medicinal chemistry. In one area, we are pursuing the design and diversity-oriented synthesis of small molecules which mimic bioactive peptide fragments crucial for programmed cell death. These structures are designed to activate apoptosis enzymes, compensating for existing irregularities in cancerous cells. Because nature is a rich source of novel "lead" structures in the search for more effective enzyme inhibitors, we also have an interest in the stereoselective synthesis of biologically active, structurally complex natural products. The development of novel, widely applicable synthetic methods is central to these efforts. In addition, we are exploring the synthesis of naturally occurring non-proteinogenic amino acids in an effort to evaluate their utility in natural product analogs and potential drug candidates.

More info here: Del Valle Group

Dr. Gopalan's major research interests are in the area of organic synthesis and environmental chemistry. Methods for the preparation of chiral intermediates using enzymatic reactions such as baker's yeast reductions and lipase catalyzed resolutions are being investigated. The subsequent use of the chirons generated from these studies to the synthesis of natural products is also of interest. Dr. Gopalan's group is also involved in the design and development of specific chelators for metal ions, with special focus on actinides.

Most of the nutritionally significant biological atmospheric nitrogen fixation is carried out by Rhizobium/ Bradyrhizobium spp. that fix nitrogen only within the nodules they form on the roots of legumes. Research in Dr. Sengupta-Gopalan's laboratory focuses on two major aspects of symbiotic N2-fixation: (i) the initial interaction between the host and the symbiont leading to the initiation of nodule formation. The goal of this project is to test the hypothesis that an internal increase in flavonoids is one of the earliest responses to Rhizobium infection and that these flavonoids are responsible for initiating nodule formation. (ii) Assimilation of fixed nitrogen with special emphasis on the key ammonia assimilatory enzymes, glutamine synthetase (GS) and glutamate synthase (GOGAT) and the genes encoding them. Because both GS and GOGAT are key enzymes in the assimilation of ammonia, an additional issue that is being addressed is how alterations in GS levels in different tissues/organs will affect the nitrogen status and the overall performance of plants. The specific objectives of this work would be (a) to understand the regulatory mechanism underlying expression of the different GS gene members in alfalfa and soybean, and (b) to modulate expression of GS and GOGAT in alfalfa in a gene member or cell specific manner and to analyze the physiological and biomechanical outcome of modulation of these enzymes.

My laboratory presently studies the bacterium Staphylococcus aureus, which causes a large percentage of infections that arise in hospital, as well as, excessive morbidity and mortality. Vancomycin remains the drug of choice for the treatment of serious infections caused by methicillin resistant S. aureus (MRSA), which are normally resistant to multiple antibiotics. However, the recent discovery of MRSA expressing vancomycin resistance leads many scientists/physicians to believe a public health disaster is looming on the horizon.

Dennis Hallford received his undergraduate and graduate training at Tarleton State University and Oklahoma State University, respectively. He has been a faculty member in the Department of Animal and Range Sciences at New Mexico State University since 1975 with teaching and research responsibilities in the areas of animal physiology and reproductive endocrinology. Dr. Hallford’s research centers around examining mechanisms controlling puberty and onset of anestrus in seasonal breeding farm animals. He operates the Endocrinology Laboratory in which radioimmunoassays of serum hormones are conducted. Hormones quantified include estrogen, progesterone, testosterone, growth hormone, insulin, FSH, LH, IGF-1 and many others. Dr. Hallford has received several teaching and research awards including the College of Agriculture and Home Economics Distinguished Teaching and Distinguished Research Awards, the Distinguished Teacher and Distinguished Service Awards from the Western Section of the American Society of Animal Science, and the Westhafer Award for Excellence in Teaching at New Mexico State University. Dr. Hallford has served as major professor for over 40 masters and doctoral students at NMSU.

Our research focuses on the development of new reagents for the synthesis of structurally complex and medicinally important compounds. A continuing goal is to develop simple reaction processes that convert simple molecules into structurally complex molecules in an efficient and reliable fashion. Current projects targets include new syntheses of steroids, isoquinoline anticancer agents, etoposide anticancer agents, and synthetic nucleosides that are potential antiviral agents.

My interests lie in the very broad areas of the evolutionary biology of birds, and of other vertebrates to a lesser degree. My research covers several areas. (1) Phylogeny reconstruction -the genealogical relationships of organisms to one another. I concentrate on deciphering interfamilial and interordinal relationships. (2) Biogeography -the correlation of patterns of phyletic divergence and the origins of new taxa to the geographic distribution of species and the formation of geophysical barriers through time. (3) Macroevolution - the plasticity and polarity of morphological evolution within lineages. This is best understood by exploring pattern in the distribution of morphological characters that are superimposed onto a phylogenetic "tree" inferred independently from molecular genetic analysis. (4) Evolutionary rate - how rates of genetic and morphological evolution differ within and between taxa. I address these diverse problems through the combined study of fossil vertebrates, comparative anatomy (particularly osteology), DNA sequencing, and DNA hybridization.

Dr. Johnson's research has two major thrusts. One involves the mechanistic investigations into the reactivity and complexation of the ferrate ion, FeO₄^2-, where iron exists in the +6 oxidation state. His other research interest focuses on the chemical remediation of organics and heavy metals in aqueous media.

How are we able to respond appropriately to events? Dr. Kroger's laboratory conducts research to understand brain mechanisms that direct our attention to information in the external and internal environments, enabling effective negotiation of day-to-day challenges. His previous work employed fMRI brain imaging to observe changes in the location of brain activity as subjects directed their attention in various ways. With fMRI it remains difficult to paint a picture of the processes interacting across these regions because the temporal order of activity in them can not be determined. EEG (brain wave) research permits ultra-fast recording that will allow us to determine the order in which areas in the brain become active, so we may understand how the different regions operate, and where the true locus of control of attention is. This methodology may finally provide an understanding of how the brain holds and manipulates information to permit complex, adaptive behavior. Together with fMRI conducted at the MIND Institute in Albuquerque, and EEG research in Dr. Kroger’s lab at NMSU, a precise description of the mechanisms for higher cognition is sought.

Since the 1990s research has been conducted on controlling computers with brain waves, bypassing traditional input devices such as keyboards and mice. However, current efforts have not progressed much beyond the first demonstrations in which a cursor was moved back and forth across a computer screen. Researcher in this field has employed overly simple ideas about how the brain operates. Tapping current knowledge about the complexly varied character of neurocognitive processes, our laboratory will explore more sophisticated and capable approaches to mental control of computer interfaces and other devices.  

Glenn Kuehn, Ph.D.
Chemistry & Biochemistry
505-646-1015
E-mail: gkuehn@nmsu.edu

See also: http://gdkuehn.nmsu.edu/

Dr. Kuehn's research deals with (1) the protective role of uncommon polyamines, norspermidine, norspermine, and caldopentamine, in tolerances of plants to drought and heat stresses, and (2) their subsequent utilization as determinants of structural protein architecture in the cell cytoskeleton.

Arbuscular mycorrhizal (AM) fungi form obligate symbioses with most plant species. Plants trade fixed carbon in the form of simple sugars for phosphorus and nitrogen taken up by the fungus from the soil. We are utilizing functional genomic approaches to broaden our understanding of this important symbiosis. Specific goals are to i) identify biochemical pathways functioning in both carbon and nitrogen transfer between the fungal symbiont and host plant roots, ii) study the regulation of key genes in these pathways via quantitative PCR methods and iii) identify signaling pathways needed to establish the symbiosis. The role of AM fungi in the bioremediation of metals and arsenic by plants is another focus of current AM research in the laboratory. MARC students with strong backgrounds in the Computer Sciences might be interested in a project focused on protein recognition. The function of a significant fraction of new proteins discovered in genomic and EST studies can not be deduced from simple amino acid sequence comparisons. An alternative approach is to use fold recognition approaches to identify matches based on predicted structural characteristics. This approach has promise because the number of different folds in the protein universe is very small compared to the number of sequences, indicating that structure is conserved much more than sequence. We have developed a new fold recognition method (Protein Classification through the Assessment of Predicted Secondary Structure or PCAPSS) that builds predicted secondary structure state hidden Markov models of orphan groups and searches the Protein Data Bank (PDB) of experimentally-determined structures.

My research program focuses on optimizing nutrient utilization by livestock in an effort to improve production and health while reducing nutrient excretion (waste) and its impact on environmental pollution.  Whole farm nutrient balance and recycling, and optimization of the efficiency of nutrient utilization are approaches to optimize production efficiency and to address the needs for more environmental friendly animal feeding operations.  My research goals are to enhance the nutrient utilization by the animal by evaluating and developing feeding programs that better meet the animal's requirements, evaluating the ideal nutrient composition concept, and improving digestibility, bioavailability, and metabolism of nutrients through nutritional and management strategies.  Specific research activities include the evaluation of mechanisms controlling nutrient utilization (digestion and absorption) and metabolism, and their biological regulation in the whole animal.  One major area of research is to investigate the ideal amino acid patterns for cattle and factors (e.g. energy source) that affect the efficiency with which each amino acid is used for production purposes.

Our laboratory is interested in determining the three-dimensional structures of small proteins in solution by multidimensional multinuclear nuclear magnetic resonance (NMR) spectroscopy. Current projects underway in the laboratory focus on relating structure to function and specificity in the Grb7 protein family. Members of this protein family have all been implicated in an increased occurrence of cancer. Specifically, Grb7 expression is up-regulated in 20-30% of breast cancers and these patients have a poor long-term survival rate. Our research is focused on unraveling the structural basis for the propensity of this protein family to bind only to specific up-stream and down-stream signaling partners. Study in this field spans a wide breadth of experimental approaches, including molecular biology, expression, and purification of proteins of interest, knowledge and implementation of data acquisition techniques using the NMR spectrometer, extensive data analysis and interpretation using available software on Unix based computers, and calculation and refinement of three-dimensional structures derived from NOE distance constraints.

Research in my laboratory focuses on the interface between population genetics, ecology, and evolutionary biology. Specifically, we are interested in quantifying the rates at which evolution proceeds and in elucidating the rules governing evolutionary change of ecological and molecular traits. Ongoing population studies address such questions as 1) at what rate does neutral evolutionary change proceed and how does that determine the balances between genetic drift, migration, and natural selection, and 2) how do population size, mating system, and the demographic characteristics of populations interact to determine the rate of evolution? At a larger evolutionary scale we are concerned with such questions as 1) at what rate do large-scale evolutionary changes occur, and 2) are changes in one trait influenced by changes in others? One common theme in our research is the interest in quantifying the demographic properties of natural populations-population size, mating system, and migration rate, for example-that determine the rate of evolutionary change. A second major theme is the interest in using quantitative models of evolution to test alternative evolutionary or biogeographic hypotheses. Finally, we are interested in applying our research to practical concerns such as those arising in conservation biology.

My research interests are mainly focused on the evolution and molecular specificity between marine organisms and their bacterial symbionts. Presently, I am working on a system that encompasses the interactions between a sepiolid squid host (Family Sepiolidae) and their bioluminescent bacterial symbionts (Genus Vibrio). This association is an ideal model system because unlike other marine symbiotic associations, both host and symbiont can be cultured separately, allowing the study of molecular signaling and physiological responses in a mutualistic interaction. In the sepiolid/Vibrio system, both squid and bacteria have been studied extensively, allowing the manipulation of different strains of symbiotic bacteria in different host squid.

The phenylpropanoid pathway is significant because it is a major pathway in plant secondary metabolism, the products of this pathway are diverse, they provide a multitude of functions in the plant, and it provides a multitude of pharmaceutical agents. An example of one of these agents is capsaicin, the pungent principle in chile fruit. Capsaicinoids are used as analgesics, in modern medical formulations, and chile has been used for centuries in mesoamerican cultures as a remedy for a wide variety of ailments. Individual capsaicinoids differ in the degree of heat, the location of perception in the mouth and throat, and the duration of their burn. There are also cultivar specific differences in the composition of capsaicinoids. Recent investigations on the structure/activity relationships or different capsaicin analogues have determined the essential structural components for interaction with nociceptive receptors. However, virtually nothing is known about the genes that control the synthesis of individual capsaicinoids, or that control the abundance of total capsaicinoids. Isolation and characterization of cDNA clones for capsaicinoid biosynthetic enzymes can be achieved using heterologous probes for steps on the pathway common to other plans, and using differential hybridization strategies for capsaicinoid-specific steps. Isolation of the capsaicinoid-specific steps will utilize a collection of genetically well described Capsicum spp. Pungent and non-pungent lines. The regulation of the phenylpropanoid pathway will then be investigated using selected cDNA clones and gene-specific probes for these cDNAs to monitor transcript accumulation.

Dr. Rayson's research interests pertain to the investigation of metal atoms and ions in complex chemical environments. These studies involve the elucidation of atomization, ionization, and excitation mechanisms occurring within the high temperature systems of inductively coupled argon plasma discharges and resistively heated graphite furnace atomizers. Alternately, studies of the chemical moieties on the cell walls of plants which are responsible for the selective binding of heavy metal ions from contaminated waters and soils are also pursued in the Rayson laboratory. The elucidation of these complex chemical processes necessitates the implementation of numerous, independent techniques. These "tools" have included the use of temporally and spectrally resolved atomic emission and absorption spectroscopies, laser excited luminescence measurements in both time and wavelength domains, multi-nuclear NMR spectroscopy, and frontal affinity chromatography.

Meticulous New Mexico homeowners squat and pull weeds for hours. While they dream of winning the "best lawn in the neighborhood" award, some researchers at New Mexico State University actually spend their summers growing weeds. To study how best to rid weeds from the Southwest, scientists like Jill Schroeder with NMSU's Agricultural Experiment Station (AES) must first grow a healthy crop of invaders. With the care gardeners give their rosebushes, weed scientists nurture their weeds.

My laboratory studies how the process of cytokinesis is coupled to chromosome segregation in animal cells. Though intensely studied for over a century, little is known regarding the molecular mechanisms that regulate the initiation of cytokinesis, and almost nothing is known regarding how the actomyosin-containing contractile ring is properly positioned in a dividing cell. In an effort to answer these questions, we are combining the power of yeast genetics with live cell imaging in large sea urchin eggs to identify and evaluate the roles of several cell cycle genes in the regulation of cytokinesis. From these lines of experimentation, we hope to understand how the final events of cell division are regulated in space and time during development and disease.

Electron transfer processes play a fundamental role in chemistry, physics and biology. Such processes can be initiated by light or, instead, result in a formation of electronically excited species able to emit optical photons. Dr. Smirnov's research program involves investigations of the photoinduced electron transfer reactions in solutions and at interfaces. Transient displacement current technique, fluorescence spectroscopy and kinetics as well as scanning probe microscopy and magnetic resonance spectroscopy are primary tools in these studies. Specific research projects include study effects of symmetry on electron transfer process, influence of electric and magnetic fields on ion-radical reactions, surface self-assembly and surface modification, and others.

I am researching the bacteria, enzymes and genes involved in the microbial biodegradation of environmental contaminants such as benzene, trichloroethylene (TCE) and the trihalomethane compounds such as chloroform. Samples from environments such as contaminated aquifers and wastewater treatment plants are being studied. Biodegradation activity (as monitored by gas chromatography) is monitored under conditions which represent aquifers in situ, that is under low-carbon, anaerobic conditions. Selection for biodegradation activity is carried out in laboratory aquifer columns which mimic many of the conditions found in contaminated aquifers. I am using genetic probes in these biodegradation studies to track particular genes of interest in environmental samples. I have developed a gene probe specific for the bacteria which reduce nitrate to nitrogen gas (denitrifying bacteria).

Our research is concerned with the design and synthesis of transition metal complexes to replicate the reactivity of oxygen- and nitrogen-activating metalloenzymes. The spectroscopic and mechanistic results obtained from these model complexes are important in understanding enzymatic chemistry. Also, the chemical transformations mediated by these enzymes are of general chemical interest; thus model compounds may have direct application in other branches of chemistry.

A fundamental question in developmental biology is how intrinsic and extrinsic factors influence the phenotype expressed by individual cells. This issue is particularly pertinent to excitable cells like muscle fibers, which express an extreme diversity of biochemical, morphological, and physiological characteristics. Currently, my lab studies the electromotor system of electric fish. In all electric fish, some skeletal muscle fibers lose their contractile apparatus and convert their phenotype into non-contractile electrocytes, i.e., electrogenic cells of the electric organ (EO). How the genes coding for a select number of muscle-specific proteins are down-regulated while others are maintain and novel genes are up-regulated, is an intriguing problem in the control of muscle and EO phenotype. My lab uses a multi-disciplinary approach that combines a range of molecular, anatomical, microscopical, and in vitro techniques to address these research goals.

Dr. Unc's interests are in the area of understanding and managing the impact of human activities on environmental quality with a special focus on contaminant microbiology of soil and water.

Dr. Urquidi's research involves the study of molecular liquids (e.g. water, HF, acetic acid) and amorphous materials (e.g. high & low density amorphous ice and optically relevant glasses) through the use of neutron and high energy X-ray diffraction techniques combined with molecular dynamic and reverse Monte Carlo simulations as aids in data interpretation. The benefits of using neutron scattering in conjunction with high energy X-rays for condensed matter research are considerable. They both serve as bulk probes due to their high penetrating power and yield complimentary structural information.

Urquidi's other research interests include the behaviour of liquid water at interfaces, with particular interest in biologically relevant surfaces and interactions. Also of interest to him is the relationship between supercooled water and the purported high to low density transition which may have implications to the existence of a second critical point for the liquid.

Dr. Haobin Wang's research is theoretical/computational study of chemical reaction dynamics.  The work is mainly carried out along two directions: the development of rigorous theoretical methods and practical computational techniques to study quantum dynamics in complex reactive processes;  and the application of these methods to important ultrafast photochemical reactions in condensed phases and nano-materials.  His research provides fundamental understandings of the photoinduced charge and energy transfer processes in various chemical and biochemical systems, which can be used to help control specific reactions as well as design new materials for solar energy conversion, molecular electronics, and other practical purposes.  The study of photochemical processes, especially photoinduced damages of biological cells,  also gives valuable insights to radiation and medical sciences.