5,668 research outputs found

    UMSL Bulletin 2023-2024

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    The 2023-2024 Bulletin and Course Catalog for the University of Missouri St. Louis.https://irl.umsl.edu/bulletin/1088/thumbnail.jp

    Simulating substrate binding sites in the S. aureus Type II NADH Dehydrogenase

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    "Type II NADH Oxidoreductase (NDH-2) from Staphylococcus aureus was established as a therapeutic target against the virulency of this bacterium and an alternative to treat Complex I-derived diseases. To accurately model interactions of NDH-2 with its substrates such as menaquinones and NADH, Coarse-Grain (CG) simulations were employed. "N/

    The Creation of a Biophysical Modeling Universe: The UNIfied and VERSatile bio response Engine

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    Radiotherapy is a crucial pillar of cancer therapy and ion beams promise superior dose conformity and potentially enhanced biological effectiveness in comparison to conventional radiation modalities. However, several factors are known to modify the biological effect of radiation. The capability to model their impact within a unified description of radiation action in conventional and ion beam fields would greatly enhance the ability to prescribe the optimal treatment and improve the knowledge of underlying mechanisms. To this end, the initial developments of the mechanistic UNIfied and VERSatile bio response Engine (UNIVERSE) are presented in this work. The effects of radiosensitizing drugs and mutations as well as DNA repair kinetics were modeled for each radiation quality. For sparsely ionizing radiation, the sparing effects at ultra-high dose-rates (uHDR) applied in FLASH radiotherapy were introduced based on oxygen depletion rates approaching measured values. Benchmarks against own or literature data are presented for each development. Challenges concerning the transition of oxygen and uHDR effects to ion beams as well as the vision of personalized biomarker-based patient plan adaptation based on UNIVERSE are discussed. UNIVERSE offers clinically relevant insights into radiobiological interdependencies and its versatility will allow it to follow future trends in radiotherapy

    Seamless Multimodal Biometrics for Continuous Personalised Wellbeing Monitoring

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    Artificially intelligent perception is increasingly present in the lives of every one of us. Vehicles are no exception, (...) In the near future, pattern recognition will have an even stronger role in vehicles, as self-driving cars will require automated ways to understand what is happening around (and within) them and act accordingly. (...) This doctoral work focused on advancing in-vehicle sensing through the research of novel computer vision and pattern recognition methodologies for both biometrics and wellbeing monitoring. The main focus has been on electrocardiogram (ECG) biometrics, a trait well-known for its potential for seamless driver monitoring. Major efforts were devoted to achieving improved performance in identification and identity verification in off-the-person scenarios, well-known for increased noise and variability. Here, end-to-end deep learning ECG biometric solutions were proposed and important topics were addressed such as cross-database and long-term performance, waveform relevance through explainability, and interlead conversion. Face biometrics, a natural complement to the ECG in seamless unconstrained scenarios, was also studied in this work. The open challenges of masked face recognition and interpretability in biometrics were tackled in an effort to evolve towards algorithms that are more transparent, trustworthy, and robust to significant occlusions. Within the topic of wellbeing monitoring, improved solutions to multimodal emotion recognition in groups of people and activity/violence recognition in in-vehicle scenarios were proposed. At last, we also proposed a novel way to learn template security within end-to-end models, dismissing additional separate encryption processes, and a self-supervised learning approach tailored to sequential data, in order to ensure data security and optimal performance. (...)Comment: Doctoral thesis presented and approved on the 21st of December 2022 to the University of Port

    Rational development of stabilized cyclic disulfide redox probes and bioreductive prodrugs to target dithiol oxidoreductases

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    Countless biological processes allow cells to develop, survive, and proliferate. Among these, tightly balanced regulatory enzymatic pathways that can respond rapidly to external impacts maintain dynamic physiological homeostasis. More specifically, redox homeostasis broadly affects cellular metabolism and proliferation, with major contributions by thiol/disulfide oxidoreductase systems, in particular, the Thioredoxin Reductase Thioredoxin (TrxR/Trx) and the Glutathione Reductase-Glutathione-Glutaredoxin (GR/GSH/Grx) systems. These cascades drive vital cellular functions in many ways through signaling, regulating other proteins' activity by redox switches, and by stoichiometric reductant transfers in metabolism and antioxidant systems. Increasing evidence argues that there is a persistent alteration of the redox environment in certain pathological states, such as cancer, that heavily involve the Trx system: upregulation and/or overactivity of the Trx system may support or drive cancer progression, making both TrxR and Trx promising targets for anti-cancer drug development. Understanding the biochemical mechanisms and connections between certain redox cascades requires research tools that interact with them. The state-of-the-art genetic tools are mostly ratiometric reporters that measure reduced:oxidized ratios of selected redox pairs or the general thiol pool. However, the precise cellular roles of the central oxidoreductase systems, including TrxR and Trx, remain inaccessible due to the lack of probes to selectively measure turnover by either of these proteins. However, such probes would allow measuring their effective reductive activity apart from expression levels in native systems, including in cells, animals, or patient samples. They are also of high interest to identify chemical inhibitors for TrxR/Trx in cells and to validate their potential use as anti-cancer agents (to date, there is no selective cellular Trx inhibitor, and most known TrxR inhibitors were not comprehensively evaluated considering selectivity and potential off-targets). However, small molecule redox imaging tools are underdeveloped: their protein specificity, spectral properties, and applicability remain poorly precedented. This work aimed to address this opportunity gap and develop novel, small molecule diagnostic and therapeutic tools to selectively target the Trx system based on a modular trigger cargo design: artificial cyclic disulfide substrates (trigger) for oxidoreductases are tethered to molecular agents (cargo) such that the cargo’s activity is masked and is re-established only through reduction by a target protein. The rational design of these novel reduction sensors to target the cell's strongest disulfide-reducing enzymes was driven by the following principles: (i) cyclic disulfide triggers with stabilized ring systems were used to gain low reduction potentials that should resist reduction except by the strongest cellular reductases, such as Trx; and (ii) the cyclic topology also offers the potential for kinetic reversibility that should select for dithiol-type redox proteins over the cellular monothiol background. Creating imaging agents based on such two-component designs to selectively measure redox protein activity in native cells required to combine the correct trigger reducibility, probe activation kinetics, and imaging modalities and to consider the overall molecular architecture. The major prior art in this field has applied cyclic 5-membered disulfides (1,2 dithiolanes) as substrates for TrxR in a similar way to create such tools. However, this motif was described elsewhere as thermodynamically instable and was due to widely used for dynamic covalent cascade reactions. By comparing a novel 1,2 dithiolane-based probe to the state-of-the-art probes, including commercial TrxR sensors, by screening a conclusive assay panel of cellular TrxR modulations, I clarified that 1,2 dithiolanes are not selective substrates for TrxR in biological settings (Nat Commun 2022). Instead, aiming for more stable ring systems and thus more robust redox probes, during this work, I developed bicyclic 6 membered disulfides (piperidine fused 1,2 dithianes) with remarkably low reduction potentials. I showed that molecular probes using them as reduction sensors can be mostly processed by thioredoxins while being stable against reduction by GSH. The thermodynamically stabilized decalin like topology of the cis-annelated 1,2 dithianes requires particularly strong reductants to be cleaved. They also select for dithiol type redox proteins, like Trx, based on kinetic reversibility and offer fast cyclization due to the preorganization by annelation (JACS 2021). This work further expanded the system’s modularity with structural cores based on piperazine-fused 1,2 dithianes with the two amines allowing independent derivatization. Diagnostic tools using them as reduction sensors proved equally robust but with highly improved activation kinetics and were thus cellularly activated. Cellular studies evolved that they are substrates for both Trxs and their protein cousins Grxs, so measuring the cellular dithiol protein pool rather than solely Trx activity (preprint 2023). Finally, a trigger based on a slightly adapted reduction sensor, a desymmetrized 1,2 thiaselenane, was designed for selective reduction by TrxR’s selenol/thiol active site, then combined with a precipitating large Stokes’ shift fluorophore and a solubilizing group, to evolve the first selective probe RX1 to measure cellular TrxR activity, which even allowed high throughput inhibitor screening (Chem 2022). The central principle of this work was further advanced to therapeutic prodrugs based on the duocarmycin cargo (CBI) with tunable potency (JACS Au 2022) that can be used to create off-to-on therapeutic prodrugs. Such CBI prodrugs employing stabilized 1,2 dichalcogenide triggers proved to be cytotoxins that depend on Trx system activity in cells. They could further be exploited for cell-line dependent reductase activity profiling by screening their redox activation indices, the reduction-dependent part of total prodrug activation, in 177 cell lines. Beyond that, these prodrugs were well-tolerated in animals and showed anti-cancer efficacy in vivo in two distinct mouse tumor models (preprint 2022). Taken together, I introduced unique monothiol-resistant reducible motifs to target the cellular Trx system with chemocompatible units for each for TrxR and Trx/Grx, where the cyclic nature of the dichalcogenides avoids activation by GSH. By using them with distinct molecular cargos, I developed novel selective fluorescent reporter probes; and introduced a new class of bioreductive therapeutic constructs based on a common modular design. These were either applied to selectively measure cellular reductase activity or to deliver cytotoxic anti cancer agents in vivo. Ongoing work aims to differentiate between the two major redox effector proteins Trx and Grx, requiring additional layers of selectivity that may be addressed by tuned molecular recognition. The flexible use of various molecular cargos allows harnessing the same cellular redox machinery by either probes or prodrugs. This allows predictive conclusions from diagnostics to be directly translated into therapy and offers great potential for future adaptation to other enzyme classes and therapeutic venues.Die zelluläre Redox-Homöostase hängt von Thiol/Disulfid-Oxidoreduktasen ab, die den Stoffwechsel, die Proliferation und die antioxidative Antwort von Zellen beeinflussen. Die wichtigsten Netzwerke sind die Thioredoxin Reduktase-Thioredoxin (TrxR/Trx) und Glutathion Reduktase-Glutathion-Glutaredoxin (GR/GSH/Grx) Systeme, die über Redox-Schalter in Substratproteinen lebenswichtige zelluläre Funktionen steuern und so an der Redox-Regulation und -Signalübertragung beteiligt sind. Persistente Veränderungen des Redoxmilieus in pathologischen Zuständen, wie z. B. bei Krebs, sind in hohem Maße mit dem Trx-System verbunden. Eine Hochregulierung und/oder Überaktivität des Trx-Systems, die bei vielen Krebsarten auftreten, unterstützt zudem das Fortschreiten des Krebswachstums, was TrxR/Trx zu vielversprechenden Zielproteinen für die Entwicklung neuer Krebsmedikamente macht. Um die biochemischen Prozesse dahinter zu erforschen, sind spezielle Techniken zur Visualisierung und Messung enzymatischer Aktivität nötig. Die hierzu geeigneten, meist genetischen Sensoren messen ratiometrisch das Verhältnis reduzierter/oxidierter Spezies in zellulärem Umfeld oder spezifisch ausgewählte Redoxpaare. Die weitere Erforschung der exakten Funktion von TrxR/Trx und deren Substrate ist jedoch durch mangelnde Nachweismethoden limitiert. Diese sind außerdem zur Validierung chemischer Hemmstoffe für TrxR/Trx in Zellen und deren potenziellen Verwendung als Krebsmittel von großem Interesse. Bislang gibt es keinen selektiven zellulären Trx-Inhibitor und potenzielle Off-Target-Effekte der bekannten TrxR-Inhibitoren wurden nicht abschließend bewertet. Ziel dieser Arbeit ist die Entwicklung niedermolekularer, diagnostischer und therapeutischer Werkzeuge, die selektiv auf das Trx-System abzielen und auf einem modularen Trigger-Cargo Design basieren. Hierzu werden zyklische Disulfid-Substrate (Trigger) für Oxidoreduktasen so mit molekularen Wirkstoffen (Cargo) verknüpft, dass dabei die Wirkstoffaktivität maskiert, und erst nach Reduktion durch ein Zielprotein wiederhergestellt wird. Diese neuartigen, synthetischen Reduktionssensoren basieren auf den folgenden Grundprinzipien: (i) Zyklische Disulfide sind thermodynamisch stabilisiert und können nur durch die stärksten Reduktasen gespalten werden; und (ii) die zyklische Topologie ermöglicht die kinetische Reversibilität der zwei Thiol-Disulfid-Austauschreaktionen, die eine erste Reaktion mit Monothiolen, wie z. B. GSH, sofort umkehrt und so eine vollständige Reduktion verhindert. Die meisten früheren Arbeiten auf diesem Gebiet verwendeten ein zyklisches, fünfgliedriges Disulfid (1,2 Dithiolan) als Substrat für TrxR. Das gleiche Strukturmotiv wurde jedoch an anderer Stelle als thermodynamisch instabil beschrieben und aufgrund dieser Eigenschaft explizit für dynamische Kaskadenreaktionen verwendet. Deshalb vergleicht diese Arbeit zu Beginn einen neuen 1,2 Dithiolan basierten fluorogenen Indikator mit bestehenden, z. T. kommerziellen, Redox Sonden für TrxR in einer Reihe von Zellkultur-Experimenten unter Modulation der zellulären TrxR Aktivität und stellt so einen Widerspruch in der Literatur klar: 1,2 Dithiolane eignen sich nicht als selektive Substrate für TrxR, da sie labil sowohl gegen die Reduktion durch andere Redoxproteine, als auch gegen den Monothiol Hintergrund in Zellen sind (Nat. Commun. 2022). Als alternatives Strukturmotiv wird in dieser Arbeit ein bizyklisches sechsgliedriges Disulfid (anneliertes 1,2 Dithian) etabliert. Durch sein niedriges Reduktionspotenzial, also seine hohe Resistenz gegen Reduktion, werden molekulare Sonden basierend auf diesem 1,2 Dithian als Reduktionssensor fast ausschließlich von Trx aktiviert, nicht aber von TrxR oder GSH (JACS 2021). Dieses Kernmotiv bestimmt dabei die Reduzierbarkeit, und damit die Enzymspezifität, durch seine zyklische Natur und die Annelierung, auch unter Verwendung unterschiedlicher Farb-/Wirkstoffe. Auf dieser Grundlage konnte die molekulare Struktur durch einen weiteren Modifikationspunkt für die flexible Verwendung weiterer funktioneller Einheiten ergänzt werden. Obwohl zelluläre Studien ergaben, dass diese neuartigen 1,2 Dithian Einheiten in Zellen sowohl Trx als auch das strukturell verwandte Grx adressieren, sind die daraus resultierenden diagnostischen Moleküle wertvoll, um den katalytischen Umsatz zellulärer Dithiol-Reduktasen, der sogenannten Trx Superfamilie, selektiv anzuzeigen (Preprint 2023). Begünstigt durch das modulare Moleküldesign stellt diese Arbeit zudem das erste Reportersystem RX1 zum selektiven Nachweis der TrxR-Aktivität in Zellen vor. Es basiert auf der Verwendung eines zyklischen, unsymmetrischen Selenenylsulfid-Sensors (1,2 Thiaselenan), der selektiv von dem einzigartigen Selenolat der TrxR angegriffen wird, und dadurch letztlich nur von TrxR reduziert werden kann. RX1 eignete sich zudem für eine Hochdurchsatz-Validierung bestehender TrxR Inhibitoren und unterstreicht dadurch den kommerziellen Nutzen derartiger Diagnostika (Chem 2022). Das zentrale Trigger-Cargo Konzept dieser Arbeit wurde für therapeutische Zwecke weiterentwickelt und nutzt dabei den einzigartigen Wirkmechanismus der Duocarmycin-Naturstoffklasse (CBI) (JACS Au 2022) zur Entwicklung reduktiv aktivierbarer Therapeutika. CBI Prodrugs basierend auf stabilisierten Redox-Schaltern (1,2 Dithiane für Trx; 1,2 Thiaselenan für TrxR) reagierten signifikant auf TrxR-Modulation in Zellen. Sie wurden darüber hinaus durch das Referenzieren ihrer Aktivität gegenüber nicht-reduzierbaren Kontrollmoleküle für die Erstellung zelllinienabhängiger Profile der Reduktaseaktivität in 177 Zelllinien genutzt. Schließlich waren diese neuen Krebsmittel im Tiermodell gut verträglich und zeigten in zwei verschiedenen Mausmodellen eine krebshemmende Wirkung (Preprint 2022b). Zusammenfassend präsentiert diese Dissertation monothiol-resistente reduzierbare Trigger-Einheiten für das zelluläre Trx-System zur Entwicklung neuartiger, selektiver Reporter-Sonden, sowie eine neue Klasse reduktiv aktivierbarer Krebsmittel auf Basis eines adaptierbaren Trigger-Cargo Designs. Diese fanden entweder zur selektiven Messung zellulärer Proteinaktivität oder zum Einsatz als Antikrebsmittel Verwendung. Es wurden chemokompatible Motive sowohl für TrxR als auch für Trx/Grx identifiziert, wobei deren zyklische Natur eine Aktivierung durch GSH verhindert. Eine weitere Differenzierung zwischen den beiden Redox-Proteinen Trx und Grx und anderen Proteinen der Trx-Superfamilie erfordert eine zusätzliche Ebene der Selektierung, z. B. durch molekulare Erkennung, und ist Gegenstand laufender Arbeiten. Die flexible Verwendung verschiedener molekularer Wirkstoffe ermöglicht dabei die „Pipeline-Entwicklung“ von Diagnostika und Therapeutika, die von der zellulären Redox-Maschinerie analog umgesetzt werden, und dadurch Schlussfolgerungen aus der Diagnostik direkt auf eine Therapie übertragbar machen. Dies birgt großes Potenzial für künftige Entwicklungen bei einer potenziellen Übertragung des modularen Konzepts auf andere Enzymklassen und therapeutische Einsatzgebiete

    Elucidation of novel biosynthetic pathways for the discovery of cyclodipeptide derivatives from Streptomyces species

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    Cyclodipeptides (CDPs) with a 2,5-diketopiperazine (DKP) as central core occur ubiquitously in living organisms, from simple bacteria and fungi to more complex ones like plants and animals. They display various biological and pharmacological effects, including antibiotic, antifungal, and antiproliferative activities. In microorganisms, CDPs are usually synthesized by one of the two distinct enzyme families, nonribosomal peptide synthetases (NRPSs), mainly occurring in fungi, or cyclodipeptide synthases (CDPSs), commonly found in bacteria. NRPS for CDP formation are comparably large (~2500 amino acids), bi-modular enzymes, using free amino acids as substrates. CDPSs on the other hand are smaller (200 – 300 amino acids) and require activated amino acyl tRNAs for peptide bond formation. In general, the formation of the DKP ring increases the stability of CDPs against proteolysis compared to their acyclic counterparts. This enables a variety of intriguing modifications carried out by tailoring enzymes. Their genetic information often lies in direct neighborhood to that of backbone enzymes, like CDPSs, arranged in biosynthetic gene clusters (BGCs). In CDPS-associated pathways, tailoring enzymes comprise cyclodipeptide oxidases (CDOs), cytochrome P450 (P450) enzymes, FeII/2-oxoglutarate dependent (FeII/2-OG) oxidases, as well as methyl- (MTs) and prenyltransferases (PTs). In this thesis, eight of such BGCs from Streptomyces species were identified using genome mining and elucidated by a combination of heterologous expression and biochemical analyses. In the first project, a BGC from Streptomyces cinnamoneus consisting of five genes was chosen for detailed investigation and termed gtm gene cluster. It codes for four enzymes, i.e. a CDPS (GtmA), a CDO (GtmBC), a P450 enzyme (GtmD), and a FeII/2-OG oxidase (GtmE). The genes were cloned in different combinations into the replicative pPWW50A vector for heterologous expression in Streptomyces albus J1074 (S. albus). Investigation using LC-MS and NMR spectroscopy revealed that GtmA synthesizes cyclo-L-Trp-L-Met, GtmBC installs a double bond at the methionine residue of the DKP, GtmD transfers a guanine onto the tryptophan moiety, and GtmE forms a second double bond at another side of the DKP. Together, this cascade results in the formation of the novel secondary metabolite guatrypmethine C. As the second dehydrogenation by GtmE displayed a novel reaction for FeII/2-OG oxidases in CDPS-dependent pathways, it was further characterized biochemically using the recombinant protein. It was proven that GtmE indeed catalyzes the conversion of the precursor guatrypmethine A to the pathway end product guatrypmethine C. No efficient conversion of the stable isomer guatrypmethine B was observed by GtmE. This experimental finding was further supported by quantum chemical calculations using density functional theory. In the second project, in cooperation with Dr. Jing Liu, a widely distributed two-gene locus, gymAB, was identified in 47 different actinobacteria. It comprises the genes gymA and gymB, coding for a CDPS and a P450 oxidase, respectively. The latter is closely related to CYP121, an essential enzyme for the viability of Mycobacterium tuberculosis. Six representative Streptomyces species were selected for functional elucidation of these BGCs. In analogy to the first project, their genes were cloned into pPWW50A and overexpressed in S. albus. Analyses of the cultural extracts by LC-MS in combination with NMR spectroscopy of the purified compounds showed that all six CDPSs produce cyclo-L-Tyr-L-Tyr (cYY) as major product. Subsequently, the P450 oxidases catalyze two different kind of reactions – either the formation of an intramolecular C-C bond within cYY resulting in mycocyclosin, or the intermolecular transfer of the nucleobases guanine or hypoxanthine, leading to the formation of the novel secondary metabolites guatyromycine A and B, respectively. The reactions catalyzed by GymBs were confirmed with biochemical assays using recombinant proteins of all six candidates. As the intramolecular coupling is the same reaction performed by CYP121 from Mycobacterium tuberculosis, the corresponding gene cluster was also expressed heterologously in the same manner. However, CYP121 merely catalyzes the formation of mycocyclosin, indicating that GymBs might have evolved from CYP121 and slightly changed during evolution. In the third project, I contributed to the elucidation of a BGC from Streptomyces aurantiacus, coding for the CDPS SasA, the PT SasB, and the MT SasC. It was proven that the sasABC gene cluster is responsible for the formation of streptoazine C. The involved PT SasB catalyzes two regular prenylations at both tryptophan residues within cyclo-L-Trp-L-Trp. By incubation with other CDPs and dehydrogenated CDPs, it was shown that SasB possesses a broad substrate flexibility and can convert at least eight other CDP derivatives efficiently

    Heterocyclic Compounds from Marine Organisms

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    Marine drugs have drawn considerable attention due to their significant biological and pharmacological properties, such as antimicrobial or antibacterial activities and antitumor effects, among others. The frequent occurrence of heterocyclic motifs in the structure of many of these targets has revealed the key role of these units as promising pharmacophores. In this Special Issue we have gathered several original papers which highlight the isolation, structural elucidation and biological essays of newly isolated heterocyclic marine drugs, as well as reviews which give an overview of the isolation, synthesis and pharmacological activities of different classes of marine heterocycles

    Ciguatoxins

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    Ciguatoxins (CTXs), which are responsible for Ciguatera fish poisoning (CFP), are liposoluble toxins produced by microalgae of the genera Gambierdiscus and Fukuyoa. This book presents 18 scientific papers that offer new information and scientific evidence on: (i) CTX occurrence in aquatic environments, with an emphasis on edible aquatic organisms; (ii) analysis methods for the determination of CTXs; (iii) advances in research on CTX-producing organisms; (iv) environmental factors involved in the presence of CTXs; and (v) the assessment of public health risks related to the presence of CTXs, as well as risk management and mitigation strategies

    The Virus Resistance Mechanism of Abortive Infection K in Lactococcus lactis

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    In nature, there is a constant battle between viruses and their hosts known as the evolutionary arms race, where they both continuously evolve to attempt to gain an advantage over the other. This evolutionary arms race has resulted in many mechanistic inventions, such as abortive infection (Abi) mechanisms in bacteria. In Abi mechanisms, viruses inject their genetic material into cells, but bacteria block phage replication by preventing one of the steps of phage maturation, typically resulting in cell death. This study looks at the Abi mechanism called AbiK, which is controlled by a protein of the same name that was discovered on a plasmid in Lactococcus lactis. A large portion of the study focuses on what happens in vivo during the AbiK mechanism. The normal wild-type infection, the abortive infection mediated by the AbiK protein, and the escape of the AbiK mechanism by a mutant phage are all studied for comparative analyses. Observations have shown that phage DNA replication is inhibited, and that transcription of the phage genes is delayed during the AbiK mechanism. The mutant phage can bypass these inhibitions, and successfully replicate its DNA and complete the phage lytic cycle. RNA-Sequencing experiments were conducted to narrow down the mechanism behind AbiK, and preliminary results indicate that AbiK depletes the nucleotide resources available in the cell, eventually resulting in cell death and inhibition of the phage replication cycle. A second part of this study focuses on the biochemistry of the AbiK protein. The AbiK protein has a polymerase activity that polymerizes an untemplated long single-stranded DNA that is covalently attached to the AbiK protein. This study identified which amino acid is used as a primer, which is tyrosine 44 on the AbiK protein. The release of protein structure prediction databases allowed for the analysis of a generated model of the AbiK protein, allowing for the elucidation of other biochemical functions the AbiK protein has. In addition to the polymerization activity, AbiK is hypothesized to bind to nucleotides or other proteins. The culmination of these studies allowed for insight on the AbiK mechanism, generating a hypothesis for future studies
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