Biochemistry, Biophysics, and Structural Biology Commons^™

Engineering And Application Of A Biosensor With Focused Ligand Specificity, Dennis Della Corte, Hugo L. Van Beek, Falk Syberg, Marcus Schallmey, Felix Tobola, Kai U. Cormann, Christine Schlicker, Philipp T. Baumann, Karin Krumbach, Sascha Sokolowsky, Connor J. Morris, Alexander Grünberger

Faculty Publications

Cell factories converting bio-based precursors to chemicals present an attractive avenue to a sustainable economy, yet screening of genetically diverse strain libraries to identify the best-performing whole-cell biocatalysts is a low-throughput endeavor. For this reason, transcriptional biosensors attract attention as they allow the screening of vast libraries when used in combination with fluorescence-activated cell sorting (FACS). However, broad ligand specificity of transcriptional regulators (TRs) often prohibits the development of such ultra-high-throughput screens. Here, we solve the structure of the TR LysG of Corynebacterium glutamicum, which detects all three basic amino acids. Based on this information, we follow a semi-rational engineering …

Ring Nmr Dynamics: Software For Analysis Of Multiple Nmr Relaxation Experiments, Martha A. Beckwith, Teddy Erazo-Colon, Bruce A. Johnson

Advanced Science Research Center

Molecular motions are fundamental to the existence of life, and NMR spectroscopy remains one of the most useful and powerful methods to measure their rates and molecular characteristics. Multiple experimental methods are available for measuring the NMR relaxation properties and these can require different methods for extracting model parameters. We present here a new software application, RING NMR Dynamics, that is designed to support analysis of multiple relaxation types. The initial release of RING NMR Dynamics supports the analysis of exponential decay experiments such as T₁ and T₂, as well as CEST and R₂ and R …

Loss Of Speg Inhibitory Phosphorylation Of Ryanodine Receptor Type-2 Promotes Atrial Fibrillation, Hannah M Campbell, Ann P Quick, Issam Abu-Taha, David Y Chiang, Carlos F Kramm, Tarah A Word, Sören Brandenburg, Mohit Hulsurkar, Katherina M Alsina, Hui-Bin Liu, Brian Martin, Dennis Uhlenkamp, Oliver M Moore, Satadru K Lahiri, Eleonora Corradini, Markus Kamler, Albert J R Heck, Stephan E Lehnart, Dobromir Dobrev, Xander H T Wehrens

Faculty, Staff and Students Publications

BACKGROUND: Enhanced diastolic calcium (Ca

METHODS: Western blotting was performed with right atrial biopsies from patients with paroxysmal AF. SPEG atrial knockout mice were generated using adeno-associated virus 9. In mice, AF inducibility was determined using intracardiac programmed electric stimulation, and diastolic Ca

RESULTS: Western blotting revealed decreased SPEG protein levels in atrial biopsies from patients with paroxysmal AF in comparison with patients in sinus rhythm. SPEG atrial-specific knockout mice exhibited increased susceptibility to pacing-induced AF by programmed electric stimulation and enhanced Ca

CONCLUSIONS: Unlike other kinases (PKA, CaMKII) that increase RyR2 activity, SPEG phosphorylation reduces RyR2-mediated sarcoplasmic reticulum Ca

Human Parainfluenza Virus Fusion Complex Glycoproteins Imaged In Action On Authentic Viral Surfaces, Tara Marcink, Tong Wang, Amédée Des Georges, Matteo Porotto, Anne Moscona

Advanced Science Research Center

Infection by human parainfluenza viruses (HPIVs) causes widespread lower respiratory diseases, including croup, bronchiolitis, and pneumonia, and there are no vaccines or effective treatments for these viruses. HPIV3 is a member of the Respirovirus species of the Paramyxoviridae family. These viruses are pleomorphic, enveloped viruses with genomes composed of single-stranded negative-sense RNA. During viral entry, the first step of infection, the viral fusion complex, comprised of the receptor-binding glycoprotein hemagglutininneuraminidase (HN) and the fusion glycoprotein (F), mediates fusion upon receptor binding. The HPIV3 transmembrane protein HN, like the receptor-binding proteins of other related viruses that enter host cells using …

Retrieving Functional Pathways Of Biomolecules From Single-Particle Snapshots, Ali Dashti, Ghoncheh Mashayekhi, Mrinal Shekhar, Danya Ben Hail, Salah Salah, Peter Schwander, Amedee Des Georges, Abhishek Singharoy, Joachim Frank, Abbas Ourmazd

Publications and Research

A primary reason for the intense interest in structural biology is the fact that knowledge of structure can elucidate macromolecular functions in living organisms. Sustained effort has resulted in an impressive arsenal of tools for determining the static structures. But under physiological conditions, macromolecules undergo continuous conformational changes, a subset of which are functionally important. Techniques for capturing the continuous conformational changes underlying function are essential for further progress. Here, we present chemically-detailed conformational movies of biological function, extracted data-analytically from experimental single-particle cryo-electron microscopy (cryo-EM) snapshots of ryanodine receptor type 1 (RyR1), a calcium-activated calcium channel engaged in the …

A Paradigm For Peptide Hormone-Gpcr Analyses, Fred Naider, Jeffrey M. Becker

Publications and Research

Work from our laboratories over the last 35 years that has focused on Ste2p, a G protein-coupled receptor (GPCR), and its tridecapeptide ligand α-factor is reviewed. Our work utilized the yeast Saccharomyces cerevisiae as a model system for understanding peptide-GPCR interactions. It explored the structure and function of synthetic α-factor analogs and biosynthetic receptor domains, as well as designed mutations of Ste2p. The results and conclusions are described using the nuclear magnetic resonance interrogation of synthetic Ste2p transmembrane domains (TMs), the fluorescence interrogation of agonist and antagonist binding, the biochemical crosslinking of peptide analogs to Ste2p, and the phenotypes of …

A Review Of The Preclinical And Clinical Efficacy Of Remdesivir, Hydroxychloroquine, And Lopinavir-Ritonavir Treatments Against Covid-19, Dawid Maciorowski, Samir Z. El Idrissi, Yash Gupta, Brian J. Medernach, Michael B. Burns, Daniel P. Becker Ph.D., Ravi Durvasula, Prakasha Kempaiah

Chemistry: Faculty Publications and Other Works

In December of 2019, an outbreak of a novel coronavirus flared in Wuhan, the capital city of the Hubei Province, China. The pathogen has been identified as a novel enveloped RNA beta-coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The virus SARS-CoV-2 is associated with a disease characterized by severe atypical pneumonia known as coronavirus 2019 (COVID-19). Typical symptoms of this disease include cough, fever, malaise, shortness of breath, gastrointestinal symptoms, anosmia, and, in severe cases, pneumonia.¹ The high-risk group of COVID-19 patients includes people over the age of 60 years as well as people with existing cardiovascular …

A Practical Guide To Mechanistic Systems Modeling In Biology Using A Logic-Based Approach, Anna Niarakis, Tomáš Helikar

Department of Biochemistry: Faculty Publications

Mechanistic computational models enable the study of regulatory mechanisms implicated in various biological processes. These models provide a means to analyze the dynamics of the systems they describe, and to study and interrogate their properties, and provide insights about the emerging behavior of the system in the presence of single or combined perturbations. Aimed at those who are new to computational modeling, we present here a practical hands-on protocol breaking down the process of mechanistic modeling of biological systems in a succession of precise steps. The protocol provides a framework that includes defining the model scope, choosing validation criteria, selecting …

Algal Biomarkers As A Proxy For Pco2: Constraints From Late Quaternary Sapropels In The Eastern Mediterranean, Caitlyn R. Witkowski, Marcel T.J. Van Der Meer, Brian Blais, Jaap S. Sinninghe Damsté, Stefan Schouten

Science and Technology Department Faculty Journal Articles

Records of carbon dioxide concentrations (partial pressure expressed as pCO2) over Earth’s history provide trends that are critical to understand our changing world. To better constrain pCO2 estimations, here we test organic pCO2 proxies against the direct measurements of pCO2 recorded in ice cores. Based on the concept of stable carbon isotopic fractionation due to photosynthetic CO2 fixation (Ɛp), we use the stable carbon isotopic composition (δ13C) of the recently proposed biomarker phytol (from all photoautotrophs), as well as the conventionally used alkenone biomarkers (from specific species) for comparison, to reconstruct pCO2 over several Quaternary …

Cautionary Tale Of Using Tris(Alkyl)Phosphine Reducing Agents With Nad+-Dependent Enzymes, Sagar M. Patel, Thomas G. Smith, Martha Morton, Kyle M. Stiers, Javier Seravalli, Stephen J. Mayclin, Thomas E. Edwards, John J. Tanner, Donald F. Becker

Department of Biochemistry: Faculty Publications

Protein biochemistry protocols typically include disulfide bond reducing agents to guard against unwanted thiol oxidation and protein aggregation. Commonly used disulfide bond reducing agents include dithiothreitol, β-mercaptoethanol, glutathione, and the tris(alkyl)phosphine compounds tris(2-carboxyethyl)phosphine (TCEP) and tris(3-hydroxypropyl)phosphine (THPP). While studying the catalytic activity of the NAD(P)H-dependent enzyme Δ¹-pyrroline-5-carboxylate reductase, we unexpectedly observed a rapid non-enzymatic chemical reaction between NAD⁺ and the reducing agents TCEP and THPP. The product of the reaction exhibits a maximum ultraviolet absorbance peak at 334 nm and forms with an apparent association rate constant of 231–491 M⁻¹ s⁻¹. The reaction is …

Atom Identifiers Generated By A Neighborhood-Specific Graph Coloring Method Enable Compound Harmonization Across Metabolic Databases, Huan Jin, Joshua M. Mitchell, Hunter N. B. Moseley

Molecular and Cellular Biochemistry Faculty Publications

Metabolic flux analysis requires both a reliable metabolic model and reliable metabolic profiles in characterizing metabolic reprogramming. Advances in analytic methodologies enable production of high-quality metabolomics datasets capturing isotopic flux. However, useful metabolic models can be difficult to derive due to the lack of relatively complete atom-resolved metabolic networks for a variety of organisms, including human. Here, we developed a neighborhood-specific graph coloring method that creates unique identifiers for each atom in a compound facilitating construction of an atom-resolved metabolic network. What is more, this method is guaranteed to generate the same identifier for symmetric atoms, enabling automatic identification of …

Indoline‐6‐Sulfonamide Inhibitors Of The Bacterial Enzyme Dape, Cory T. Reidl, Tahirah K. Heath, Iman Darwish, Rachel M. Torrez, Maxwell Moore, Elliot Gild, Boguslaw P. Nocek, Anna Starus, Richard C. Holz, Daniel P. Becker Ph.D.

Chemistry: Faculty Publications and Other Works

Inhibitors of the bacterial enzyme dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE; EC 3.5.1.18) hold promise as antibiotics with a new mechanism of action. Herein we describe the discovery of a new series of indoline sulfonamide DapE inhibitors from a high-throughput screen and the synthesis of a series of analogs. Inhibitory potency was measured by a ninhydrin-based DapE assay recently developed by our group. Molecular docking experiments suggest active site binding with the sulfonamide acting as a zinc-binding group (ZBG).

Rethinking Fda Regulation Of Complex Products, Philip E. Alford

Minnesota Journal of Law, Science & Technology

No abstract provided.

Homicide And Drug Trafficking In Impoverished Communities In Brazil, Elenice De Souza Oliveira, Braulio Figueiredo Alves Da Silva, Flavio Luiz Sapori, Gabriela Gomes Cardoso

Department of Justice Studies Faculty Scholarship and Creative Works

Many studies demonstrate that homicides are heavily concentrated in impoverished neighborhoods, but not all socially disadvantaged neighborhoods are hotbeds of violence. Conducted in Belo Horizonte, Brazil, this study hypothesizes that the association between high rates of homicide and impoverished areas is influenced by the emergence of a specific type of street drug-dealing common to favelas (slums). The study applies econometric techniques to police data on homicides and drug arrests from 2008 to 2011, as well as 2010 Census data, to test its hypothesis. The findings provide insight into the development of crime prevention policies in areas of high social vulnerability.

Current Scenario Of Covid-19 With Epidemiological And Phylogenetic Analysis Of Pakistani Coronavirus: A Review, Asma Altaf, Wafa Iqbal, Sidra Younis, Farah Deeba

Journal of Bioresource Management

A novel corona virus named as 2019 n-CoV was identified to be the actual cause of an outbreak of respiratory illness in Wuhan, China beginning in late December 2019. This respiratory disease was named as COVID-19 by WHO. There are many countries affected by COVID-19 including Pakistan. In this review we have provided a brief introduction of COVID-19 and discussed epidemiological and phylogenetic analysis of Pakistani novel corona virus strain. Our epidemiological analysis of data till 16^th May 2020 showed rapidly increasing number of new cases, while at the same time a higher recovery rate than number of deaths …

Estimating Partial Body Ionizing Radiation Exposure By Automated Cytogenetic Biodosimetry, Peter Rogan

Biochemistry Publications

Purpose: Inhomogeneous exposures to ionizing radiation can be detected and quantified with the Dicentric Chromosome Assay (DCA) of metaphase cells. Complete automation of interpretation of the DCA for whole body irradiation has significantly improved throughput without compromising accuracy, however low levels of residual false positive dicentric chromosomes (DCs) have confounded its application for partial body exposure determination.

Materials and Methods: We describe a method of estimating and correcting for false positive DCs in digitally processed images of metaphase cells. Nearly all DCs detected in unirradiated calibration samples are introduced by digital image processing. DC frequencies of irradiated calibration …

Structural Insights Of Transcriptionally Active, Full-Length Androgen Receptor Coactivator Complexes, Xinzhe Yu, Ping Yi, Ross A Hamilton, Hong Shen, Muyuan Chen, Charles E Foulds, Michael A Mancini, Steven J Ludtke, Zhao Wang, Bert W O'Malley

Faculty, Staff and Students Publications

Steroid receptors activate gene transcription by recruiting coactivators to initiate transcription of their target genes. For most nuclear receptors, the ligand-dependent activation function domain-2 (AF-2) is a primary contributor to the nuclear receptor (NR) transcriptional activity. In contrast to other steroid receptors, such as ERα, the activation function of androgen receptor (AR) is largely dependent on its ligand-independent AF-1 located in its N-terminal domain (NTD). It remains unclear why AR utilizes a different AF domain from other receptors despite that NRs share similar domain organizations. Here, we present cryoelectron microscopy (cryo-EM) structures of DNA-bound full-length AR and its complex structure …

Electronic-Cigarette Vehicles And Flavoring Affect Lung Function And Immune Responses In A Murine Model, Brittany N. Szafran, Rakeysha Pinkston, Zakia Perveen, Matthew K. Ross, Timothy Morgan, Daniel B. Paulsen, Arthur L. Penn, Barbara L. F. Kaplan, Alexandra Noel

Faculty Publications

The use of electronic nicotine delivery systems (ENDS), also known as electronic-cigarettes (e-cigs), has raised serious public health concerns, especially in light of the 2019 outbreak of e-cig or vaping product use-associated acute lung injury (EVALI). While these cases have mostly been linked to ENDS that contain vitamin E acetate, there is limited research that has focused on the chronic pulmonary effects of the delivery vehicles (i.e., without nicotine and flavoring). Thus, we investigated lung function and immune responses in a mouse model following exposure to the nearly ubiquitous e-cig delivery vehicles, vegetable glycerin (VG) and propylene glycol (PG), used …

Mesenchymal Stem Cells And Their Extracellular Vesicles: A Potential Game Changer For The Covid-19 Crisis, Dina H. Kassem, Mohamed M. Kamal

Pharmacy

Corona virus disease 2019 (COVID-19) is a global public health crisis. The high infectivity of the disease even from non-symptomatic infected patients, together with the lack of a definitive cure or preventive measures are all responsible for disease outbreak. The severity of COVID-19 seems to be mostly dependent on the patients’ own immune response. The over-activation of the immune system in an attempt to kill the virus, can cause a “cytokine storm” which in turn can induce acute respiratory distress syndrome (ARDS), as well as multi-organ damage, and ultimately may lead to death. Thus, harnessing the immunomodulatory properties of mesenchymal …

Pointing The Zinc Finger On Protein Folding: Energetic Investigation Into The Role Of The Metal-Ion In The Metal-Induced Protein Folding Of Zinc Finger Motifs, Inna Bakman-Sanchez

Dissertations, Theses, and Capstone Projects

Interactions between inorganic metal-ion cofactors and organic protein scaffolds are important for the proper structure and function of metalloproteins. Zinc finger proteins (ZFPs) are an example of proteins with such crucial metal-protein interactions. Incorporation of the Zn(II)-ion into ZFPs allows for their correct folding into structures that can carry out vital biological functions which include gene expression and tumor suppression. In addition, engineered ZFPs have shown to be promising genetic therapeutics in the clinic. And yet, there is still a gap in a quantitative understanding of the energetic contribution of the metal-protein interactions towards the structure and function of these …

Machine Learning Applications For Drug Repurposing, Hansaim Lim

Dissertations, Theses, and Capstone Projects

The cost of bringing a drug to market is astounding and the failure rate is intimidating. Drug discovery has been of limited success under the conventional reductionist model of one-drug-one-gene-one-disease paradigm, where a single disease-associated gene is identified and a molecular binder to the specific target is subsequently designed. Under the simplistic paradigm of drug discovery, a drug molecule is assumed to interact only with the intended on-target. However, small molecular drugs often interact with multiple targets, and those off-target interactions are not considered under the conventional paradigm. As a result, drug-induced side effects and adverse reactions are often neglected …

Small Molecule Synthetic Carbohydrate Receptors, Marcelo F. Bravo Carranco

Dissertations, Theses, and Capstone Projects

Carbohydrate – receptor interactions are often involved in the attachment of viruses to host cells, and this docking is a necessary step in the virus life cycle that precedes infection and, ultimately, replication. Despite the conserved structures of the glycans involved in docking, they are still considered “undruggable”, meaning these glycans are beyond the scope of conventional pharmacological strategies. Recent advances in the development of synthetic carbohydrate receptors (SCRs) – small molecules that bind carbohydrates – could bring carbohydrate-receptor interactions within the purview of druggable targets. Here we discuss the role of carbohydrate-receptor interactions in viral infection, the evolution of …

Characterization Of Retinal Biomechanical Properties Using Brillouin Microscopy, Yogeshwari S Ambekar, Manmohan Singh, Giuliano Scarcelli, Elda M Rueda, Benjamin M Hall, Ross A Poché, Kirill V Larin

Faculty, Staff and Students Publications

SIGNIFICANCE: The retina is critical for vision, and several diseases may alter its biomechanical properties. However, assessing the biomechanical properties of the retina nondestructively is a challenge due to its fragile nature and location within the eye globe. Advancements in Brillouin spectroscopy have provided the means for nondestructive investigations of retina biomechanical properties.

AIM: We assessed the biomechanical properties of mouse retinas using Brillouin microscopy noninvasively and showed the potential of Brillouin microscopy to differentiate the type and layers of retinas based on stiffness.

APPROACH: We used Brillouin microscopy to quantify stiffness of fresh and paraformaldehyde (PFA)-fixed retinas. As further …

Mtor-Initiated Metabolic Switch And Degeneration In The Retinal Pigment Epithelium, Young-Mi Go, Jing Zhang, Jolyn Fernandes, Christopher Litwin, Rui Chen, Theodore G Wensel, Dean P Jones, Jiyang Cai, Yan Chen

Faculty, Staff and Students Publications

The retinal pigment epithelium (RPE) is a particularly vulnerable tissue to age-dependent degeneration. Over the life span, the RPE develops an expanded endo-lysosomal compartment to maintain the high efficiency of phagocytosis and degradation of photoreceptor outer segments (POS) necessary for photoreceptor survival. As the assembly and activation of the mechanistic target of rapamycin complex 1 (mTORC1) occur on the lysosome surface, increased lysosome mass with aging leads to higher mTORC1 activity. The functional consequences of hyperactive mTORC1 in the RPE are unclear. In the current study, we used integrated high-resolution metabolomic and genomic approaches to examine mice with RPE-specific deletion …

Berry Phenolic And Volatile Extracts Inhibit Pro-Inflammatory Cytokine Secretion In Lps-Stimulated Raw264.7 Cells Through Suppression Of Nf-Κb Signaling Pathway, Inah Gu, Cindi Brownmiller, Nathan Blaine Stebbins, Andy Mauromostakos, Luke Howard, Sun-Ok Lee

Food Science Faculty Publications and Presentations

Berries are a rich source of phytochemicals, especially phenolics well known for protective activity against many chronic diseases. Berries also contain a complex mixture of volatile compounds that are responsible for the unique aromas of berries. However, there is very limited information on the composition and potential health benefits of berry volatiles. In this study, we isolated phenolic and volatile fractions from six common berries and characterized them by HPLC/HPLC-MS and GC/GC-MS, respectively. Berry phenolic and volatile fractions were evaluated for an anti-inflammatory effect using lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells by measuring levels of pro-inflammatory cytokines and the nuclear factor-kappa …

Pressure Driven Desalination Utilizing Nanomaterials, Fangyou Xie

Master's Theses

Nanomaterials such as graphene oxide and carbon nanotubes, have demonstrated excellent properties for membrane desalination, including decrease of maintenance, increase of flux rate, simple solution casting, and impressive chemical inertness. Here, two projects are studied to investigate nanocarbon based membrane desalination. The first project is to prepare hybrid membranes with amyloid fibrils intercalated with graphene oxide sheets. The addition of protein amyloid fibrils expands the interlayer spacing between graphene oxide nanosheets and introduces additional functional groups in the diffusion pathways, resulting in increase of flux rate and rejection rate for the organic dyes. Amyloid fibrils also provide structural assistance to …

Synthesis, Structure Elucidation And Selected Biological Activities Of Ag(I) And Au(I) Complexes Constructed From Thiosemicarbazone And Phosphine Ligands, Syahrina Nur ‘Ain Abdul Halim

Student Works (2020-2029)

New Ag(I) and Au(I) mixed ligand complexes were synthesised using thiosemicarbazone and phosphine in search of a new biologically active compounds. CHN elemental analysis, powder X-ray diffraction (PXRD), single crystal X-ray diffraction as well as several spectroscopic techniques such as FT-IR, Energy-dispersive X-ray (EDX), 1H, 13C, and 31P{1H} NMR were performed to elucidate the structure of these complexes. Elemental analysis suggested that the stoichiometry of the complexes formed by the reaction of Ag nitrate with thiosemicarbazone in the presence of phosphine was indeed 1:2:1 molar ratio, while for the Au to be in 1:1:1 molar ratio. The Ag and Au …

Pollen-Mediated Gene Flow And Transfer Of Resistance Alleles From Herbicide-Resistant Broadleaf Weeds, Amit J. Jhala, Jason K. Norsworthy, Zahoor A. Ganie, Lynn M. Sosnoskie, Hugh J. Beckie, Carol A. Mallory-Smith, Jun Liu, Wei Wei, Junming Wang, David E. Stoltenberg

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Pollen-mediated gene flow (PMGF) refers to the transfer of genetic information (alleles) from one plant to another compatible plant. With the evolution of herbicide-resistant (HR) weeds, PMGF plays an important role in the transfer of resistance alleles from HR to susceptible weeds; however, little attention is given to this topic. The objective of this work was to review reproductive biology, PMGF studies, and interspecific hybridization, as well as potential for herbicide resistance alleles to transfer in the economically important broadleaf weeds including common lambsquarters, giant ragweed, horseweed, kochia, Palmer amaranth, and waterhemp. The PMGF studies involving these species reveal that …

Defining Relictual Biodiversity: Conservation Units In Speckled Dace (Leuciscidae: Rhinichthys Osculus) Of The Greater Death Valley Ecosystem, Steven M. Mussmann, Marlis R. Douglas, David D. Oakey, Michael E. Douglas

Biological Sciences Faculty Publications and Presentations

The tips in the tree of life serve as foci for conservation and management, yet clear delimitations are masked by inherent variance at the species–population interface. Analyses using thousands of nuclear loci can potentially sort inconsistencies, yet standard categories applied to this parsing are themselves potentially conflicting and/or subjective [e.g., DPS (distinct population segments); DUs (Diagnosable Units-Canada); MUs (management units); SSP (subspecies); ESUs (Evolutionarily Significant Units); and UIEUs (uniquely identified evolutionary units)]. One potential solution for consistent categorization is to create a comparative framework by accumulating statistical results from independent studies and evaluating congruence among data sets. Our study illustrates …

1,4-Dioxane Biodegradation In Propanotrophs: Molecular Foundations And Implications For Environmental Remediation, Li Fei

Dissertations

1,4-Dioxane (dioxane) has emerged with an escalating concern given its human carcinogenicity and widespread occurrence in groundwater. Bioremediation is promising as an effective and cost-efficient treatment alternative for in situ or ex situ cleanup of dioxane and co-existing pollutants in the field. Soluble di-iron monooxygenases (SDIMOs) are reputed for their essential roles in initiating the cleavage of dioxane and other pollutants. In this doctoral dissertation, molecular foundations for SDIMOs-mediated dioxane biodegradation are untangled to promote the development and implication of site-specific bioremediation and natural attenuation strategies. This dissertation focused on propanotrophic bacteria given their pivotal roles in dioxane metabolism and …