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Molecular Biology

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2021

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Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

High-Resolution Cryo-Electron Microscopy Structure Of Photosystem Ii From The Mesophilic Cyanobacterium, Synechocystis Sp. Pcc 6803, Christopher J. Gisriel, Jimin Wang, Jinchan Liu, David A. Flesher, Krystle M. Reiss, Hao-Li Huang, Ke R. Yang, William H. Armstrong, M. R. Gunner, Victor S. Batista, Richard J. Debus, Gary W. Brudvig Dec 2021

High-Resolution Cryo-Electron Microscopy Structure Of Photosystem Ii From The Mesophilic Cyanobacterium, Synechocystis Sp. Pcc 6803, Christopher J. Gisriel, Jimin Wang, Jinchan Liu, David A. Flesher, Krystle M. Reiss, Hao-Li Huang, Ke R. Yang, William H. Armstrong, M. R. Gunner, Victor S. Batista, Richard J. Debus, Gary W. Brudvig

Publications and Research

Photosystem II (PSII) enables global-scale, light-driven water oxidation. Genetic manipulation of PSII from the mesophilic cyanobacterium Synechocystis sp. PCC 6803 has provided insights into the mechanism of water oxidation; however, the lack of a highresolution structure of oxygen-evolving PSII from this organism has limited the interpretation of biophysical data to models based on structures of thermophilic cyanobacterial PSII. Here, we report the cryo-electron microscopy structure of PSII from Synechocystis sp. PCC 6803 at 1.93-Å resolution. A number of differences are observed relative to thermophilic PSII structures, including the following: the extrinsic subunit PsbQ is maintained, the C terminus of the …


Late-Life Exercise Mitigates Skeletal Muscle Epigenetic Aging, Kevin A. Murach, Andrea L. Dimet-Wiley, Yuan Wen, Camille R. Brightwell, Christine M. Latham, Cory M. Dungan, Christopher S. Fry, Stanley J. Watowich Dec 2021

Late-Life Exercise Mitigates Skeletal Muscle Epigenetic Aging, Kevin A. Murach, Andrea L. Dimet-Wiley, Yuan Wen, Camille R. Brightwell, Christine M. Latham, Cory M. Dungan, Christopher S. Fry, Stanley J. Watowich

Center for Muscle Biology Faculty Publications

There are functional benefits to exercise in muscle, even when performed late in life, but the contributions of epigenetic factors to late-life exercise adaptation are poorly defined. Using reduced representation bisulfite sequencing (RRBS), ribosomal DNA (rDNA) and mitochondrial-specific examination of methylation, targeted high-resolution methylation analysis, and DNAge™ epigenetic aging clock analysis with a translatable model of voluntary murine endurance/resistance exercise training (progressive weighted wheel running, PoWeR), we provide evidence that exercise may mitigate epigenetic aging in skeletal muscle. Late-life PoWeR from 22–24 months of age modestly but significantly attenuates an age-associated shift toward promoter hypermethylation. The epigenetic age of muscle …


Cryptococcus Neoformans Melanization Incorporates Multiple Catecholamines To Produce Polytypic Melanin, Rosanna P. Baker, Christine Chrissian, Ruth E. Stark, Arturo Casadevall Dec 2021

Cryptococcus Neoformans Melanization Incorporates Multiple Catecholamines To Produce Polytypic Melanin, Rosanna P. Baker, Christine Chrissian, Ruth E. Stark, Arturo Casadevall

Publications and Research

Melanin is a major virulence factor in pathogenic fungi that enhances the ability of fungal cells to resist immune clearance. Cryptococcus neoformans is an important human pathogenic fungus that synthesizes melanin from exogenous tissue catecholamine precursors during infection, but the type of melanin made in cryptococcal meningoencephalitis is unknown. We analyzed the efficacy of various catecholamines found in brain tissue in supporting melanization using animal brain tissue and synthetic catecholamine mixtures reflecting brain tissue proportions. Solid-state NMR spectra of the melanin pigment produced from such mixtures yielded more melanin than expected if only the preferred constituent dopamine had been incorporated, …


Enhancing Therapeutic Approaches For Melanoma Patients Targeting Epigenetic Modifiers., Maria Gracia-Hernandez, Zuleima Munoz, Alejandro Villagra Dec 2021

Enhancing Therapeutic Approaches For Melanoma Patients Targeting Epigenetic Modifiers., Maria Gracia-Hernandez, Zuleima Munoz, Alejandro Villagra

Biochemistry and Molecular Medicine Faculty Publications

Melanoma is the least common but deadliest type of skin cancer. Melanomagenesis is driven by a series of mutations and epigenetic alterations in oncogenes and tumor suppressor genes that allow melanomas to grow, evolve, and metastasize. Epigenetic alterations can also lead to immune evasion and development of resistance to therapies. Although the standard of care for melanoma patients includes surgery, targeted therapies, and immune checkpoint blockade, other therapeutic approaches like radiation therapy, chemotherapy, and immune cell-based therapies are used for patients with advanced disease or unresponsive to the conventional first-line therapies. Targeted therapies such as the use of BRAF and …


Expanding The Conservation Genomics Toolbox: Incorporating Structural Variants To Enhance Genomic Studies For Species Of Conservation Concern, Stephanie J. Galla Dec 2021

Expanding The Conservation Genomics Toolbox: Incorporating Structural Variants To Enhance Genomic Studies For Species Of Conservation Concern, Stephanie J. Galla

Biology Faculty Publications and Presentations

Structural variants (SVs) are large rearrangements (>50 bp) within the genome that impact gene function and the content and structure of chromosomes. As a result, SVs are a significant source of functional genomic variation, that is, variation at genomic regions underpinning phenotype differences, that can have large effects on individual and population fitness. While there are increasing opportunities to investigate functional genomic variation in threatened species via single nucleotide polymorphism (SNP) data sets, SVs remain understudied despite their potential influence on fitness traits of conservation interest. In this future-focused Opinion, we contend that characterizing SVs offers the conservation genomics …


Recovery Of Altered Diabetic Myofibroblast Heterogeneity And Gene Expression Associated With Cd301b+ Macrophages, Maryellen R. Haas, Darlene V. Nguyen, Brett A. Shook Nov 2021

Recovery Of Altered Diabetic Myofibroblast Heterogeneity And Gene Expression Associated With Cd301b+ Macrophages, Maryellen R. Haas, Darlene V. Nguyen, Brett A. Shook

Biochemistry and Molecular Medicine Faculty Publications

No abstract provided.


Structure Of A Monomeric Photosystem Ii Core Complex From A Cyanobacterium Acclimated To Far-Red Light Reveals The Functions Of Chlorophylls D And F, Christopher J. Gisriel, Gaozhong Shen, Ming-Yang Ho, Vasily Kurashov, David A. Flesher, Jimin Wang, William H. Armstrong, John H. Golbeck, Marilyn R. Gunner, David J. Vinyard, Richard J. Debus, Gary W. Brudvig, Donald A. Bryant Nov 2021

Structure Of A Monomeric Photosystem Ii Core Complex From A Cyanobacterium Acclimated To Far-Red Light Reveals The Functions Of Chlorophylls D And F, Christopher J. Gisriel, Gaozhong Shen, Ming-Yang Ho, Vasily Kurashov, David A. Flesher, Jimin Wang, William H. Armstrong, John H. Golbeck, Marilyn R. Gunner, David J. Vinyard, Richard J. Debus, Gary W. Brudvig, Donald A. Bryant

Publications and Research

Far-red light (FRL) photoacclimation in cyanobacteria provides a selective growth advantage for some terrestrial cyanobacteria by expanding the range of photosynthetically active radiation to include far-red/near-infrared light (700–800 nm). During this photoacclimation process, photosystem II (PSII), the water:plastoquinone photooxidoreductase involved in oxygenic photosynthesis, is modified. The resulting FRL-PSII is comprised of FRL-specific core subunits and binds chlorophyll (Chl) d and Chl f molecules in place of several of the Chl a molecules found when cells are grown in visible light. These new Chls effectively lower the energy canonically thought to define the “red limit” for light required to drive photochemical …


Dual Activities Of Acc Synthase: Novel Clues Regarding The Molecular Evolution Of Acs Genes, Chang Xu, Bowei Hao, Gongling Sun, Yuanyuan Mei, Lifang Sun, Yunmei Sun, Yibo Wang, Yongyan Zhang, Wei Zhang, Mengyuan Zhang, Yue Zhang, Dan Wang, Zihe Rao, Xin Li, Jeffery Shen, Ning Ning Wang Nov 2021

Dual Activities Of Acc Synthase: Novel Clues Regarding The Molecular Evolution Of Acs Genes, Chang Xu, Bowei Hao, Gongling Sun, Yuanyuan Mei, Lifang Sun, Yunmei Sun, Yibo Wang, Yongyan Zhang, Wei Zhang, Mengyuan Zhang, Yue Zhang, Dan Wang, Zihe Rao, Xin Li, Jeffery Shen, Ning Ning Wang

Life Sciences Faculty Research

Ethylene plays profound roles in plant development. The rate-limiting enzyme of ethylene biosynthesis is 1-aminocyclopropane-1-carboxylate (ACC) synthase (ACS), which is generally believed to be a single-activity enzyme evolving from aspartate aminotransferases. Here, we demonstrate that, in addition to catalyzing the conversion of S-adenosyl-methionine to the ethylene precursor ACC, genuine ACSs widely have Cβ-S lyase activity. Two N-terminal motifs, including a glutamine residue, are essential for conferring ACS activity to ACS-like proteins. Motif and activity analyses of ACS-like proteins from plants at different evolutionary stages suggest that the ACC-dependent pathway is uniquely developed in seed plants. A putative catalytic mechanism for …


Anal Human Papillomavirus Infection Among Men Who Have Sex With Men And Transgender Women Living With And Without Hiv In Pakistan: Findings From A Cross-Sectional Study, Muslima Ejaz, Soren Andersson, Salma Batool, Tazeen Saeed Ali, Anna Mia Ekström Nov 2021

Anal Human Papillomavirus Infection Among Men Who Have Sex With Men And Transgender Women Living With And Without Hiv In Pakistan: Findings From A Cross-Sectional Study, Muslima Ejaz, Soren Andersson, Salma Batool, Tazeen Saeed Ali, Anna Mia Ekström

Community Health Sciences

Objectives: The aim of this study was to determine the prevalence of infection, genotypes and risk factors for human papillomavirus (HPV) among men who have sex with men (MSM) and transgender women living with and without HIV in Pakistan. Anal infection with HPV is very common worldwide among MSM, particularly among MSM living with HIV. The high prevalence of HIV among MSM and male-to-female transgendered individuals in Pakistan is a significant health concern since access to screening and health-seeking is often delayed in this stigmatised key population.
Design: This cross-sectional study was conducted between March 2016 and November 2017.
Participants, …


Cryo-Em Structure Of Mechanosensitive Channel Ynai Using Sma2000: Challenges And Opportunities, Claudio Catalano, Danya Ben-Hail, Weihua Qiu, Paul Blount, Amedee Des Georges, Youzhong Guo Oct 2021

Cryo-Em Structure Of Mechanosensitive Channel Ynai Using Sma2000: Challenges And Opportunities, Claudio Catalano, Danya Ben-Hail, Weihua Qiu, Paul Blount, Amedee Des Georges, Youzhong Guo

Publications and Research

Mechanosensitive channels respond to mechanical forces exerted on the cell membrane and play vital roles in regulating the chemical equilibrium within cells and their environment. Highresolution structural information is required to understand the gating mechanisms of mechanosensitive channels. Protein-lipid interactions are essential for the structural and functional integrity of mechanosensitive channels, but detergents cannot maintain the crucial native lipid environment for purified mechanosensitive channels. Recently, detergent-free systems have emerged as alternatives for membrane protein structural biology. This report shows that while membrane-active polymer, SMA2000, could retain some native cell membrane lipids on the transmembrane domain of the mechanosensitive-like YnaI channel, …


An Empirical Pipeline For Personalized Diagnosis Of Lafora Disease Mutations, M. Kathryn Brewer, Maria Machio-Castello, Rosa Viana, Jeremiah L. Wayne, Andrea Kuchtová, Zoe R. Simmons, Sarah Sternbach, Sheng Li, Maria Adelaida García-Gimeno, Jose M. Serratosa, Pascual Sanz, Craig W. Vander Kooi, Matthew S. Gentry Oct 2021

An Empirical Pipeline For Personalized Diagnosis Of Lafora Disease Mutations, M. Kathryn Brewer, Maria Machio-Castello, Rosa Viana, Jeremiah L. Wayne, Andrea Kuchtová, Zoe R. Simmons, Sarah Sternbach, Sheng Li, Maria Adelaida García-Gimeno, Jose M. Serratosa, Pascual Sanz, Craig W. Vander Kooi, Matthew S. Gentry

Molecular and Cellular Biochemistry Faculty Publications

Lafora disease (LD) is a fatal childhood dementia characterized by progressive myoclonic epilepsy manifesting in the teenage years, rapid neurological decline, and death typically within ten years of onset. Mutations in either EPM2A, encoding the glycogen phosphatase laforin, or EPM2B, encoding the E3 ligase malin, cause LD. Whole exome sequencing has revealed many EPM2A variants associated with late-onset or slower disease progression. We established an empirical pipeline for characterizing the functional consequences of laforin missense mutations in vitro using complementary biochemical approaches. Analysis of 26 mutations revealed distinct functional classes associated with different outcomes that were supported by clinical …


Oxidative Dna Damage Modulates Genome And Epigenome Integrity Via Base Excision Repair, Pawlos S. Tsegay Oct 2021

Oxidative Dna Damage Modulates Genome And Epigenome Integrity Via Base Excision Repair, Pawlos S. Tsegay

FIU Electronic Theses and Dissertations

Oxidative DNA damage is one of the leading causes of genome instability, cell death, and diseases. It is repaired by DNA base excision repair (BER), during which repair and translesion DNA polymerases may incorporate damaged nucleotides and mediate RNA-guided DNA repair induced by DNA replication and gene transcription leading to the modulation of genome stability. On the other hand, oxidative DNA damage may result in cellular epigenetic responses to regulate DNA repair, altering genome stability and integrity. In this dissertation, we revealed the molecular mechanisms underlying the misincorporation of oxidized nucleotides, 5′,8-cyclo-2-cyclodeoxyadenosine (cdA) and RNA-guided base lesion repair mediated by …


Salicylic Acid: A Key Regulator Of Redox Signalling 1 And Plant Immunity, Mohd Saleem, Qazi Fariddudin, Christian Castroverde Oct 2021

Salicylic Acid: A Key Regulator Of Redox Signalling 1 And Plant Immunity, Mohd Saleem, Qazi Fariddudin, Christian Castroverde

Biology Faculty Publications

In plants, the reactive oxygen species (ROS) formed during normal conditions are essential in regulating several processes, like stomatal physiology, pathogen immunity and developmental signaling. However, biotic and abiotic stresses can cause ROS over-accumulation leading to oxidative stress. Therefore, a suitable equilibrium is vital for redox homeostasis in plants, and there have been major advances in this research arena. Salicylic acid (SA) is known as a chief regulator of ROS; however, the underlying mechanisms remain largely unexplored. SA plays an important role in establishing the hypersensitive response (HR) and systemic acquired resistance (SAR). This is underpinned by a robust and …


A Conserved Structural Role For The Walker-A Lysine In P-Loop Containing Kinases, Fatlum Hajredini, Ranajeet Ghose Oct 2021

A Conserved Structural Role For The Walker-A Lysine In P-Loop Containing Kinases, Fatlum Hajredini, Ranajeet Ghose

Publications and Research

Bacterial tyrosine kinases (BY-kinases) and shikimate kinases (SKs) comprise two structurally divergent P-loop containing enzyme families that share similar catalytic site geometries, most notably with respect to their Walker-A, Walker-B, and DxD motifs. We had previously demonstrated that in BY-kinases, a specific interaction between the Walker-A and Walker-B motifs, driven by the conserved “catalytic” lysine housed on the former, leads to a conformation that is unable to efficiently coordinate Mg2+•ATP and is therefore incapable of chemistry. Here, using enhanced sampling molecular dynamics simulations, we demonstrate that structurally similar interactions between the Walker-A and Walker-B motifs, also mediated by …


Mutations In Several Auxin Biosynthesis Genes And Their Effects On Plant Phenotypes In Arabidopsis, Gabriela Hernandez, Lauren Huebner, Bethany Karlin Zolman Sep 2021

Mutations In Several Auxin Biosynthesis Genes And Their Effects On Plant Phenotypes In Arabidopsis, Gabriela Hernandez, Lauren Huebner, Bethany Karlin Zolman

Undergraduate Research Symposium

Auxins are important hormones in plants that regulate growth and development. Disruptions in the auxin biosynthesis pathway result in morphological changes in phenotypes in the model plant Arabidopsis thaliana, including differences in root and leaf formation. Mutations in the Tryptophan Aminotransferase of Arabidopsis (TAA1) and YUCCA (YUC4) genes interfere with the plant's ability to synthesize Indole-3-acetic acid (IAA), the primary auxin involved in plant development. IBR1 and IBR3 act in the multistep conversion of indole-3-butyric acid (IBA) to IAA. ILL2, IAR3, and ILR1 hydrolyze IAA-amino acid conjugates into free IAA. The goal of …


Aurora Kinase A Inhibition Reverses The Warburg Effect And Elicits Unique Metabolic Vulnerabilities In Glioblastoma, Trang T. T. Nguyen, Enyuan Shang, Chang Shu, Sungsoo Kim, Angeliki Mela, Nelson Humala, Aayushi Mahajan, Hee Won Yang, Hasan Orhan Akman, Catarina M. Quinzii, Guoan Zhang, Mike-Andrew Westhoff, Georg Karpel-Massler, Jeffrey N. Bruce, Peter Canoll, Markus D. Siegelin Sep 2021

Aurora Kinase A Inhibition Reverses The Warburg Effect And Elicits Unique Metabolic Vulnerabilities In Glioblastoma, Trang T. T. Nguyen, Enyuan Shang, Chang Shu, Sungsoo Kim, Angeliki Mela, Nelson Humala, Aayushi Mahajan, Hee Won Yang, Hasan Orhan Akman, Catarina M. Quinzii, Guoan Zhang, Mike-Andrew Westhoff, Georg Karpel-Massler, Jeffrey N. Bruce, Peter Canoll, Markus D. Siegelin

Publications and Research

Aurora kinase A (AURKA) has emerged as a drug target for glioblastoma (GBM). However, resistance to therapy remains a critical issue. By integration of transcriptome, chromatin immunoprecipitation sequencing (CHIP-seq), Assay for Transposase-Accessible Chromatin sequencing (ATAC-seq), proteomic and metabolite screening followed by carbon tracing and extracellular flux analyses we show that genetic and pharmacological AURKA inhibition elicits metabolic reprogramming mediated by inhibition of MYC targets and concomitant activation of Peroxisome Proliferator Activated Receptor Alpha (PPARA) signaling. While glycolysis is suppressed by AURKA inhibition, we note an increase in the oxygen consumption rate fueled by enhanced fatty acid oxidation (FAO), which was …


Complete Mitochondrial Genome Sequence Of The Gulf Coast Tick (Amblyomma Maculatum), Amanda E. Brenner, Rahul Raghavan Sep 2021

Complete Mitochondrial Genome Sequence Of The Gulf Coast Tick (Amblyomma Maculatum), Amanda E. Brenner, Rahul Raghavan

Biology Faculty Publications and Presentations

The complete circularized mitochondrial genome sequence of Amblyomma maculatum is 14,803 bp long. It encodes 13 protein coding genes, 2 rRNA genes, 22 tRNA genes, 2 tick box motifs, and 2 control regions. The gene arrangement and content are consistent with those of previously reported Metastriata tick mitochondrial genomes.


Decoding The Roles Of Astrocytes And Hedgehog Signaling In Medulloblastoma, Terence Teixeira Duarte, Silvia Aparecida Teixeira, Luis Gonzalez-Reyes, Rui Manuel Reis Aug 2021

Decoding The Roles Of Astrocytes And Hedgehog Signaling In Medulloblastoma, Terence Teixeira Duarte, Silvia Aparecida Teixeira, Luis Gonzalez-Reyes, Rui Manuel Reis

Publications and Research

The molecular evolution of medulloblastoma is more complex than previously imagined, as emerging evidence suggests that multiple interactions between the tumor cells and components of the tumor microenvironment (TME) are important for tumor promotion and progression. The identification of several molecular networks within the TME, which interact with tumoral cells, has provided new clues to understand the tumorigenic roles of many TME components as well as potential therapeutic targets. In this review, we discuss the most recent studies regarding the roles of astrocytes in supporting sonic hedgehog (SHH) subgroup medulloblastoma (MB) and provide an overview of MB progression through SHH …


Bioactive Recombinant Human Oncostatin M For Nmr-Based Screening In Drug Discovery, Olga A. Mass, Joseph Tuccinardi, Luke Woodbury, Cody L. Wolf, Bri Grantham, Kelsey Holdaway, Xinzhu Pu, Matthew D. King, Don L. Warner, Cheryl L. Jorcyk, Lisa R. Warner Aug 2021

Bioactive Recombinant Human Oncostatin M For Nmr-Based Screening In Drug Discovery, Olga A. Mass, Joseph Tuccinardi, Luke Woodbury, Cody L. Wolf, Bri Grantham, Kelsey Holdaway, Xinzhu Pu, Matthew D. King, Don L. Warner, Cheryl L. Jorcyk, Lisa R. Warner

Biomolecular Research Center Publications and Presentations

Oncostatin M (OSM) is a pleiotropic, interleukin-6 family inflammatory cytokine that plays an important role in inflammatory diseases, including inflammatory bowel disease, rheumatoid arthritis, and cancer progression and metastasis. Recently, elevated OSM levels have been found in the serum of COVID-19 patients in intensive care units. Multiple anti-OSM therapeutics have been investigated, but to date no OSM small molecule inhibitors are clinically available. To pursue a high-throughput screening and structure-based drug discovery strategy to design a small molecule inhibitor of OSM, milligram quantities of highly pure, bioactive OSM are required. Here, we developed a reliable protocol to produce highly pure …


Development Of High Value Oil Traits Using The Model Oilseed Crop Camelina Sativa, Evan Updike Aug 2021

Development Of High Value Oil Traits Using The Model Oilseed Crop Camelina Sativa, Evan Updike

Department of Biochemistry: Dissertations, Theses, and Student Research

Plant oils are an important source of food, fuel, and feed in our society today. The oil found in the seeds of plants is composed almost entirely of triacylglycerol (TAG) molecules, which consist of three fatty acids esterified to a glycerol backbone. As crude oil supplies decline, vegetable oils are gaining traction as a renewable substitute to petroleum-based materials in fuels, lubricants, and specialty oleochemicals. However, as it currently stands vegetable oils do not possess the properties necessary to fill the void of a petroleum free world.

To address this problem, plant biotechnologists have done extensive work on genetic engineering …


Enhancing The Interoperability Of Glycan Data Flow Between Chebi, Pubchem, And Glygen., Rahi Navelkar, Gareth Owen, Venkatesh Mutherkrishnan, Paul Thiessen, Tiejun Cheng, Evan Bolerlton, Nathan Edwards, Michael Tiemeyer, Matthew P Campbell, Maria Martin, Jeet Vora, Robel Kahsay, Raja Mazumder Jul 2021

Enhancing The Interoperability Of Glycan Data Flow Between Chebi, Pubchem, And Glygen., Rahi Navelkar, Gareth Owen, Venkatesh Mutherkrishnan, Paul Thiessen, Tiejun Cheng, Evan Bolerlton, Nathan Edwards, Michael Tiemeyer, Matthew P Campbell, Maria Martin, Jeet Vora, Robel Kahsay, Raja Mazumder

Biochemistry and Molecular Medicine Faculty Publications

Glycans play a vital role in health, disease, bioenergy, biomaterials, and bio-therapeutics. As a result, there is keen interest to identify and increase glycan data in bioinformatics databases like ChEBI and PubChem, and connecting them to resources at the EMBL-EBI and NCBI to facilitate access to important annotations at a global level. GlyTouCan is a comprehensive archival database that contains glycans obtained primarily through batch upload from glycan repositories, glycoprotein databases, and individual laboratories. In many instances, the glycan structures deposited in GlyTouCan may not be fully defined or have supporting experimental evidence and citations. Databases like ChEBI and PubChem …


Awegnn: Auto-Parametrized Weighted Element-Specific Graph Neural Networks For Molecules., Timothy Szocinski, Duc Duy Nguyen, Guo-Wei Wei Jul 2021

Awegnn: Auto-Parametrized Weighted Element-Specific Graph Neural Networks For Molecules., Timothy Szocinski, Duc Duy Nguyen, Guo-Wei Wei

Mathematics Faculty Publications

While automated feature extraction has had tremendous success in many deep learning algorithms for image analysis and natural language processing, it does not work well for data involving complex internal structures, such as molecules. Data representations via advanced mathematics, including algebraic topology, differential geometry, and graph theory, have demonstrated superiority in a variety of biomolecular applications, however, their performance is often dependent on manual parametrization. This work introduces the auto-parametrized weighted element-specific graph neural network, dubbed AweGNN, to overcome the obstacle of this tedious parametrization process while also being a suitable technique for automated feature extraction on these internally complex …


Limitations Of 16s Rrna Gene Sequencing To Characterize Lactobacillus Species In The Upper Genital Tract, Jessica L. O'Callaghan, Dana Willner, Melissa Buttini, Flavia Huygens, Elise S. Pelzer Jul 2021

Limitations Of 16s Rrna Gene Sequencing To Characterize Lactobacillus Species In The Upper Genital Tract, Jessica L. O'Callaghan, Dana Willner, Melissa Buttini, Flavia Huygens, Elise S. Pelzer

Arts & Sciences Articles

The endometrial cavity is an upper genital tract site previously thought as sterile, however, advances in culture-independent, next-generation sequencing technology have revealed that this low-biomass site harbors a rich microbial community which includes multiple Lactobacillus species. These bacteria are considered to be the most abundant non-pathogenic genital tract commensals. Next-generation sequencing of the female lower genital tract has revealed significant variation amongst microbial community composition with respect to Lactobacillus sp. in samples collected from healthy women and women with urogenital conditions. The aim of this study was to evaluate our ability to characterize members of the genital tract microbial community …


Genetically Encoded Multivalent Liquid Glycan Array Displayed On M13 Bacteriophage, Amira Khalil, Mirat Sojitra, Jasmine Maghera, Emily Rodrigues, Eric J. Carpenter, Shaurya Seth, Daniel Ferrer Vinals, Todd L. Lowary Jul 2021

Genetically Encoded Multivalent Liquid Glycan Array Displayed On M13 Bacteriophage, Amira Khalil, Mirat Sojitra, Jasmine Maghera, Emily Rodrigues, Eric J. Carpenter, Shaurya Seth, Daniel Ferrer Vinals, Todd L. Lowary

Pharmacy

The central dogma of biology does not allow for the study of glycans using DNA sequencing. We report a liquid glycan array (LiGA) platform comprising a library of DNA ‘barcoded’ M13 virions that display 30–1,500 copies of glycans per phage. A LiGA is synthesized by acylation of the phage pVIII protein with a dibenzocyclooctyne, followed by ligation of azido-modified glycans. Pulldown of the LiGA with lectins followed by deep sequencing of the barcodes in the bound phage decodes the optimal structure and density of the recognized glycans. The LiGA is target agnostic and can measure the glycan-binding profile of lectins, …


High And Low Toxin Producing Strains Of Karenia Brevis Differ Significantly In The Redox Proteome, Lipid Profiles, And Xanthophyll Cycle Pigments, Ricardo Colon Jun 2021

High And Low Toxin Producing Strains Of Karenia Brevis Differ Significantly In The Redox Proteome, Lipid Profiles, And Xanthophyll Cycle Pigments, Ricardo Colon

FIU Electronic Theses and Dissertations

The dinoflagellate Karenia brevis, blooms annually in the Gulf of Mexico, producing a suite of neurotoxins known as the brevetoxins. The cellular toxin content of K. brevis, however, is highly variable between or even within strains. I investigated biochemical differences between high (KbHT) and low (KbLT) toxin producing cultures both derived from the Wilson strain, related to energy-dependent quenching (qE) by photosystem II, and the content of reduced thiols of the proteome. By characterizing the xanthophyll content of the two strains I was able to determine that KbLT performs qE inconsistently. To investigate the …


Type I Topoisomerases As Potential Targets For Therapeutics, Ahmed Seddek Jun 2021

Type I Topoisomerases As Potential Targets For Therapeutics, Ahmed Seddek

FIU Electronic Theses and Dissertations

DNA topoisomerases are universal enzymes that control the topological features of DNA in all forms of life. This study aims to find potential inhibitors of some of the DNA topoisomerases in bacteria and humans that can be developed into potential therapeutics.

The first aim of this study is to find potential inhibitors of bacterial topoisomerase I that can be developed into antibiotics. There is an urgent need to develop novel antibiotics to overcome the world-wide health crisis of antimicrobial resistance. Virtual screening and biochemical assays were combined to screen thousands of compounds for potential inhibitors of bacterial topoisomerase I. NSC76027 …


Protein Motifs For Proton Transfers That Build The Transmembrane Proton Gradient, Divya Kaur, Umesh Khaniya, Yingying Zhang, M. R. Gunner Jun 2021

Protein Motifs For Proton Transfers That Build The Transmembrane Proton Gradient, Divya Kaur, Umesh Khaniya, Yingying Zhang, M. R. Gunner

Publications and Research

Biological membranes are barriers to polar molecules, so membrane embedded proteins control the transfers between cellular compartments. Protein controlled transport moves substrates and activates cellular signaling cascades. In addition, the electrochemical gradient across mitochondrial, bacterial and chloroplast membranes, is a key source of stored cellular energy. This is generated by electron, proton and ion transfers through proteins. The gradient is used to fuel ATP synthesis and to drive active transport. Here the mechanisms by which protons move into the buried active sites of Photosystem II (PSII), bacterial RCs (bRCs) and through the proton pumps, Bacteriorhodopsin (bR), Complex I and Cytochrome …


Algebraic Graph-Assisted Bidirectional Transformers For Molecular Property Prediction, Dong Chen, Kaifu Gao, Duc Duy Nguyen, Xin Chen, Yi Jiang, Guo-Wei Wei, Feng Pan Jun 2021

Algebraic Graph-Assisted Bidirectional Transformers For Molecular Property Prediction, Dong Chen, Kaifu Gao, Duc Duy Nguyen, Xin Chen, Yi Jiang, Guo-Wei Wei, Feng Pan

Mathematics Faculty Publications

The ability of molecular property prediction is of great significance to drug discovery, human health, and environmental protection. Despite considerable efforts, quantitative prediction of various molecular properties remains a challenge. Although some machine learning models, such as bidirectional encoder from transformer, can incorporate massive unlabeled molecular data into molecular representations via a self-supervised learning strategy, it neglects three-dimensional (3D) stereochemical information. Algebraic graph, specifically, element-specific multiscale weighted colored algebraic graph, embeds complementary 3D molecular information into graph invariants. We propose an algebraic graph-assisted bidirectional transformer (AGBT) framework by fusing representations generated by algebraic graph and bidirectional transformer, as well as …


Synphilin-1 And Its Effects On Pathogenesis Of Parkinson’S Disease, Mirghani Mohamed Jun 2021

Synphilin-1 And Its Effects On Pathogenesis Of Parkinson’S Disease, Mirghani Mohamed

Honors Scholar Theses

Parkinson's Disease (PD) is a progressive neurodegenerative and movement disorder primarily caused by the degradation of dopaminergic neurons. Known markers of neurodegeneration in PD are Lewy Bodies, which are fibrillar aggregates that are found in the brains of PD patients. Lewy Bodies can accumulate from specific mutations in the SNCA gene that codes for alpha-synuclein, a protein enriched in presynaptic neurons. A mutated SNCA gene can cause conformational aggregates of alpha-synuclein to form toxic species mediating neuronal death. Research into alpha-synuclein has led to the discovery of a binding partner known as synphilin-1 that is also found in protein aggregates …


Diffusive Search And Trajectories On Tubular Networks A Propagator Approach, Zubenelgenubi C. Scott, Aidan I. Brown, Saurabh S. Mogre, Laura M. Westrate Jun 2021

Diffusive Search And Trajectories On Tubular Networks A Propagator Approach, Zubenelgenubi C. Scott, Aidan I. Brown, Saurabh S. Mogre, Laura M. Westrate

University Faculty Publications and Creative Works

Several organelles in eukaryotic cells, including mitochondria and the endoplasmic reticulum, form interconnected tubule networks extending throughout the cell. These tubular networks host many biochemical pathways that rely on proteins diffusively searching through the network to encounter binding partners or localized target regions. Predicting the behavior of such pathways requires a quantitative understanding of how confinement to a reticulated structure modulates reaction kinetics. In this work, we develop both exact analytical methods to compute mean first passage times and efficient kinetic Monte Carlo algorithms to simulate trajectories of particles diffusing in a tubular network. Our approach leverages exact propagator functions …