Microbiology
Microbiology is a flourishing discipline with current advances in all areas from atomic-level structures to genomics to metabolism to microbe-host interactions to microbial ecology. The broad microbiology group centered within the Department of Biological Sciences covers all of these areas and includes a strong basis for technological development. This group anchors the undergraduate and graduate programs in microbiology and provides research and training interactions at many levels. The diverse backgrounds and research interests of this group leads to many collaborations, both on campus and around the world. Our on-campus involvement includes a variety of centers, such as the Bindley Bioscience Center, the Genomics Center and the Energy Center, and with faculty from across campus involved in the Purdue University Life Science (PULSe) graduate program.
Research is currently being conducted in structural biology (viral structure, viral-host interactions, metabolite and toxin receptors, transport and drug efflux membrane proteins, genomics of bacteria and cyanobacteria, molecular genetics, bacterial physiology and response to environmental stresses, metabolic modeling, energy transducing membrane proteins of bacteria and cyanobacteria, detection of problematic microorganisms in industrial environments, construction of recombinant bacterial strains to evaluate antimicrobial products, microbial ecology and bioremediation, as well as microbe-host and host-pathogen interactions.
Applegate, Bruce
Associate Professor
Department of Food Science
Detection of viable foodborne pathogens using bateriophage; automated extraction of nucleic acids from various matrices; enumeration of microorganisms (i.e. pathogens and other organisms) using quantitative PCR; the use of bioreporters in bioelectronics; metabolic engineering; detection of problematic microorganisms in industrial environments; construction of recombinant bacterial strains to rapidly evaluate antimicrobial products; microbial ecology.
Csonka, Laszlo
Professor of Biological Sciences
(Microbiology) Mechanisms of the responses of bacteria to osmotic stress; genetic engineering of plant cells with increased tolerance of salinity stress.
Gelvan, Stan (Member of Development and Disease)
Edwin Umbarger Distinguished Professor of Biology
Our research investigates how a soil bacterium, Agrobacterium tumefaciens, genetically engineers plants. Agrobacterium transfers a piece of bacterial DNA, the T-(transferred) DNA, to wounded plant cells where it makes its way through the cytoplasm to the nucleus. Once in the nucleus, T-DNA integrates into the host genome and expresses genes. Under normal circumstances, these genes cause the tumorous disease Crown Gall on plants. However, scientists have learned to manipulate T-DNA, replacing disease genes with genes of benefit to the plant. Many genetically engineered crop plants with desirable traits (disease resistance, herbicide tolerance, and enhanced nutritional value) were generated using Agrobacterium. Our laboratory investigates the role of plant genes and proteins in this natural genetic engineering process. We have identified plant genes involved in bacterial attachment to plant cells, T-DNA and Virulence protein transfer to and cytoplasmic trafficking within plants, T-DNA nuclear targeting, and T-DNA integration. Recently, we have been able to manipulate some of these plant genes to improve Agrobacterium transformation efficiency. We are currently working with agricultural biotechnology companies to improve the genetic engineering of crops.
Luo, Zhao-Qing (Member of Development and Disease)
Our laboratory is interested in understanding the cellular and molecular mechanisms that allow microbial pathogens to survive and multiply within the hostile host cells. We use Legionella pneumophila, the causative agent of Legionnaires disease as a model organism. This bacterium is a facultative intracellular pathogen capable of growing in a vacuole within macrophages as well as fresh water amoebae. After uptake, the Legionella-containing vacuole (LCV) in its early phase evades fusion with the lysosomal network and later is transformed into a compartment with characteristics of rough endoplasmic reticulum. Biogenesis of this replicative vacuole requires the Dot/Icm Type IV secretion system that injects hundreds of effector proteins into target host cells. Our current focus is to analyze biochemical and cell biological activities conferred by these proteins and their roles in promoting the unique trafficking of the Legionella-containing vacuole in phagocytic cells. In particular, we are interested in identification of host proteins whose activities are modulated by substrates of the Dot/Icm system and how such modulation contributes to successful intracellular bacterial growth. The long term goal of these studies is to elucidate the molecular mechanisms underlying how this bacterium subverts host signal transduction pathways to establish a successful infection, such information will be invaluable in combating diseases caused by Legionella and other vacuolar pathogens.
Mattoo, Seema (Member of Development and Disease)
Updating
Morgan, John (School of Chemical Engineering)
Associate Professor of Chemical Engineering
Professor Morgan's research group is interested in engineering metabolic pathways towards increased production of chemicals as well as novel biologically active metabolites. We are combining molecular biology with mathematical modeling of metabolism that enables the rational design of modifications to existing pathways. The approaches we employ span scales from manipulating the molecular structure of enzymes to bioreactor design and operation strategies
Nakatsu, Cindy (Purdue Agriculture, Agronomy)
Professor
of Agronomy
Current reseearch in: Impact of anthropogenic factors on microbial community structure
Ramkrishna, Doraiswami (School of Chemical Engineering)
Harry Creighton Peffer Distinguished Professor of Chemical Engineering
Professor Ramkrishna's research group is motivated by ideas in the application of mathematics to solving problems in chemical and biochemical reaction engineering, biotechnology and biomedical engineering. Their research ideas arise from linear (operator methods) and nonlinear analysis of ordinary and partial differential equations, stochastic processes, and population balance modeling involving integro-partial differential equations.
Sherman, Louis
Professor of Biological Sciences
Dr. Sherman's research interests center on cyanobacteria and he has studied the processes of photosynthesis, nitrogen fixation and gene regulation. He has been particularly interested in the impact of environmental changes on gene transcription and the corresponding impact on cyanobacterial physiology
Cyanobacteria have become wonderful and versatile model organisms for the study of photosynthesis, nitrogen fixation and responses to environmental stresses. Current research can help answer questions involved with environmental concerns, alternative energy uses (i.e., solar energy), and health concerns such as microbial toxins and the design of new drugs. The genomic sequence of the model organism Synechocystis sp. PCC 6803 was completed a decade ago and the genomic sequences of 6 Cyanothece strains have now been completed. The lab has constructed microarrays for all of these strains and has been involved with high throughput experiments in proteomics and metabolomics. The unicellular Cyanothece strains show robust metabolic and circadian rhythms and performs photosynthesis and N2-fixation at different times of the day and night. This organism is key to a large project aimed at understanding the regulation of such processes and the assembly of membrane complexes. Strains in this genus have been shown to produce copious quantities of H2, organic acids, fatty acids, exopolysaccharides and polyhydroxyalkanoates and are now being analyzed in much greater detail. This analysis will help us determine how best to use specific strains for large-scale production of alternative energy compounds, such as H2, butanol or fatty acids.
Zhou, Daoguo (Member of Development and Disease)
My research focuses on the cell biology of infectious diseases, in particular human intestinal diseases caused by pathogenic Salmonella and E. coli. These pathogens cause intestinal diarrhea and may lead to more serious systematic infections in humans. Both pathogenic Salmonella and E. coli utilize the type III protein secretion/translocation system (TTSS) to inject bacterial "effector proteins" into host cells to exploit host cell functions to survive in the hostile environment and cause inflammatory responses. We aim to understand the molecular and cellular mechanism of how these effectors function to enable the pathogens to circumvent our host immune system to cause diseases. We currently have projects studying the role(s) of actin dynamics in Salmonella and E. coli infections and how bacterial effectors exploit the host ubiquitination pathways to induce inflammatory responses.