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  1. Article ; Online: Correction for Banerjee et al., "

    Banerjee, Dithi / Umland, Timothy C / Panepinto, John C

    mSphere

    2023  Volume 8, Issue 5, Page(s) e0040623

    Language English
    Publishing date 2023-09-26
    Publishing country United States
    Document type Journal Article ; Published Erratum
    ISSN 2379-5042
    ISSN (online) 2379-5042
    DOI 10.1128/msphere.00406-23
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: De Novo

    Banerjee, Dithi / Umland, Timothy C / Panepinto, John C

    mSphere

    2016  Volume 1, Issue 6

    Abstract: The use of amphotericin B (AmB) in conjunction with 5-fluorocytosine (5-FC) is known to be the optimal therapy for treating cryptococcosis, but the mechanism by which 5-FC synergizes with AmB is unknown. In this study, we generated ... ...

    Abstract The use of amphotericin B (AmB) in conjunction with 5-fluorocytosine (5-FC) is known to be the optimal therapy for treating cryptococcosis, but the mechanism by which 5-FC synergizes with AmB is unknown. In this study, we generated a
    Language English
    Publishing date 2016-11-16
    Publishing country United States
    Document type Journal Article
    ISSN 2379-5042
    ISSN 2379-5042
    DOI 10.1128/mSphere.00191-16
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Re-evaluating the approach to drug target discovery in multidrug-resistant Gram-negative bacilli.

    Umland, Timothy C / Schultz, L Wayne / Russo, Thomas A

    Future microbiology

    2014  Volume 9, Issue 10, Page(s) 1113–1116

    MeSH term(s) Anti-Infective Agents/isolation & purification ; Anti-Infective Agents/pharmacology ; Drug Discovery/methods ; Drug Discovery/trends ; Drug Resistance, Multiple, Bacterial ; Genes, Bacterial ; Genes, Essential ; Gram-Negative Bacteria/drug effects
    Chemical Substances Anti-Infective Agents
    Language English
    Publishing date 2014
    Publishing country England
    Document type Editorial ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ISSN 1746-0921
    ISSN (online) 1746-0921
    DOI 10.2217/fmb.14.72
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Repurposed dihydroorotate dehydrogenase inhibitors with efficacy against drug-resistant

    Russo, Thomas A / Umland, Timothy C / Deng, Xiaoyi / El Mazouni, Farah / Kokkonda, Sreekanth / Olson, Ruth / Carlino-MacDonald, Ulrike / Beanan, Janet / Alvarado, Cassandra L / Tomchick, Diana R / Hutson, Alan / Chen, Hong / Posner, Bruce / Rathod, Pradipsinh K / Charman, Susan A / Phillips, Margaret A

    Proceedings of the National Academy of Sciences of the United States of America

    2022  Volume 119, Issue 51, Page(s) e2213116119

    Abstract: New antimicrobials are needed for the treatment of extensively drug- ... ...

    Abstract New antimicrobials are needed for the treatment of extensively drug-resistant
    MeSH term(s) Humans ; Mice ; Animals ; Acinetobacter baumannii ; Dihydroorotate Dehydrogenase ; Microbial Sensitivity Tests ; Meropenem ; Enzyme Inhibitors/pharmacology ; Enzyme Inhibitors/chemistry ; Anti-Bacterial Agents/pharmacology ; Anti-Bacterial Agents/therapeutic use
    Chemical Substances Dihydroorotate Dehydrogenase ; Meropenem (FV9J3JU8B1) ; Enzyme Inhibitors ; Anti-Bacterial Agents
    Language English
    Publishing date 2022-12-13
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2213116119
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Influenza A polymerase subunit PB2 possesses overlapping binding sites for polymerase subunit PB1 and human MAVS proteins.

    Patel, Deendayal / Schultz, L Wayne / Umland, Timothy C

    Virus research

    2012  Volume 172, Issue 1-2, Page(s) 75–80

    Abstract: Influenza A virus is an important human pathogen accounting for widespread morbidity and mortality, with new strains emerging from animal reservoirs possessing the potential to cause pandemics. The influenza A RNA-dependent RNA polymerase complex ... ...

    Abstract Influenza A virus is an important human pathogen accounting for widespread morbidity and mortality, with new strains emerging from animal reservoirs possessing the potential to cause pandemics. The influenza A RNA-dependent RNA polymerase complex consists of three subunits (PA, PB1, and PB2) and catalyzes viral RNA replication and transcription activities in the nuclei of infected host cells. The PB2 subunit has been implicated in pathogenicity and host adaptation. This includes the inhibition of type I interferon induction through interaction with the host's mitochondrial antiviral signaling protein (MAVS), an adaptor molecule of RIG-I-like helicases. This study reports the identification of the cognate PB2 and MAVS interaction domains necessary for complex formation. Specifically, MAVS residues 1-150, containing both the CARD domain and the N-terminal portion of the proline rich-region, and PB2 residues 1-37 are essential for PB2-MAVS virus-host protein-protein complex formation. The three α-helices constituting PB2 (1-37) were tested to determine their relative influence in complex formation, and Helix3 was observed to promote the primary interaction with MAVS. The PB2 MAVS-binding domain unexpectedly coincided with its PB1-binding domain, indicating an important dual functionality for this region of PB2. Analysis of these interaction domains suggests both virus and host properties that may contribute to host tropism. Additionally, the results of this study suggest a new strategy to develop influenza A therapeutics by simultaneously blocking PB2-MAVS and PB2-PB1 protein-protein interactions and their resulting activities.
    MeSH term(s) Adaptor Proteins, Signal Transducing/metabolism ; Binding Sites ; Cell Line ; Humans ; Influenza A Virus, H1N1 Subtype/physiology ; Protein Binding ; Protein Interaction Domains and Motifs ; Protein Interaction Mapping ; RNA Replicase/metabolism ; Viral Proteins/metabolism
    Chemical Substances Adaptor Proteins, Signal Transducing ; MAVS protein, human ; PB2 protein, Influenzavirus A ; Viral Proteins ; influenza virus polymerase basic protein 1 ; RNA Replicase (EC 2.7.7.48)
    Language English
    Publishing date 2012-12-12
    Publishing country Netherlands
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 605780-9
    ISSN 1872-7492 ; 0168-1702
    ISSN (online) 1872-7492
    ISSN 0168-1702
    DOI 10.1016/j.virusres.2012.12.003
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Crystal structure of 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase from the ESKAPE pathogen Acinetobacter baumannii.

    Sutton, Kristin A / Breen, Jennifer / Russo, Thomas A / Schultz, L Wayne / Umland, Timothy C

    Acta crystallographica. Section F, Structural biology communications

    2016  Volume 72, Issue Pt 3, Page(s) 179–187

    Abstract: The enzyme 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase catalyzes the sixth step of the seven-step shikimate pathway. Chorismate, the product of the pathway, is a precursor for the biosynthesis of aromatic amino acids, siderophores and metabolites ... ...

    Abstract The enzyme 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase catalyzes the sixth step of the seven-step shikimate pathway. Chorismate, the product of the pathway, is a precursor for the biosynthesis of aromatic amino acids, siderophores and metabolites such as folate, ubiquinone and vitamin K. The shikimate pathway is present in bacteria, fungi, algae, plants and apicomplexan parasites, but is absent in humans. The EPSP synthase enzyme produces 5-enolpyruvylshikimate 3-phosphate and phosphate from phosphoenolpyruvate and shikimate 3-phosphate via a transferase reaction, and is the target of the herbicide glyphosate. The Acinetobacter baumannii gene encoding EPSP synthase, aroA, has previously been demonstrated to be essential during host infection for the growth and survival of this clinically important drug-resistant ESKAPE pathogen. Prephenate dehydrogenase is also encoded by the bifunctional A. baumannii aroA gene, but its activity is dependent upon EPSP synthase since it operates downstream of the shikimate pathway. As part of an effort to evaluate new antimicrobial targets, recombinant A. baumannii EPSP (AbEPSP) synthase, comprising residues Ala301-Gln756 of the aroA gene product, was overexpressed in Escherichia coli, purified and crystallized. The crystal structure, determined to 2.37 Å resolution, is described in the context of a potential antimicrobial target and in comparison to EPSP synthases that are resistant or sensitive to the herbicide glyphosate.
    MeSH term(s) 3-Phosphoshikimate 1-Carboxyvinyltransferase/chemistry ; Acinetobacter baumannii/enzymology ; Amino Acid Sequence ; Bacterial Proteins/chemistry ; Catalytic Domain ; Crystallization ; Crystallography, X-Ray ; Models, Molecular ; Protein Conformation, alpha-Helical ; Shikimic Acid/analogs & derivatives ; Shikimic Acid/chemistry
    Chemical Substances Bacterial Proteins ; Shikimic Acid (29MS2WI2NU) ; shikimic acid-3-phosphate (63959-45-5) ; 3-Phosphoshikimate 1-Carboxyvinyltransferase (EC 2.5.1.19)
    Language English
    Publishing date 2016-02-16
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ISSN 2053-230X
    ISSN (online) 2053-230X
    DOI 10.1107/S2053230X16001114
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: The Response Regulator BfmR Is a Potential Drug Target for Acinetobacter baumannii.

    Russo, Thomas A / Manohar, Akshay / Beanan, Janet M / Olson, Ruth / MacDonald, Ulrike / Graham, Jessica / Umland, Timothy C

    mSphere

    2016  Volume 1, Issue 3

    Abstract: Identification and validation is the first phase of target-based antimicrobial development. BfmR (RstA), a response regulator in a two-component signal transduction system (TCS) in Acinetobacter baumannii, is an intriguing potential antimicrobial target. ...

    Abstract Identification and validation is the first phase of target-based antimicrobial development. BfmR (RstA), a response regulator in a two-component signal transduction system (TCS) in Acinetobacter baumannii, is an intriguing potential antimicrobial target. A unique characteristic of BfmR is that its inhibition would have the dual benefit of significantly decreasing in vivo survival and increasing sensitivity to selected antimicrobials. Studies on the clinically relevant strain AB307-0294 have shown BfmR to be essential in vivo. Here, we demonstrate that this phenotype in strains AB307-0294 and AB908 is mediated, in part, by enabling growth in human ascites fluid and serum. Further, BfmR conferred resistance to complement-mediated bactericidal activity that was independent of capsular polysaccharide. Importantly, BfmR also increased resistance to the clinically important antimicrobials meropenem and colistin. BfmR was highly conserved among A. baumannii strains. The crystal structure of the receiver domain of BfmR was determined, lending insight into putative ligand binding sites. This enabled an in silico ligand binding analysis and a blind docking strategy to assess use as a potential druggable target. Predicted binding hot spots exist at the homodimer interface and the phosphorylation site. These data support pursuing the next step in the development process, which includes determining the degree of inhibition needed to impact growth/survival and the development a BfmR activity assay amenable to high-throughput screening for the identification of inhibitors. Such agents would represent a new class of antimicrobials active against A. baumannii which could be active against other Gram-negative bacilli that possess a TCS with shared homology. IMPORTANCE Increasing antibiotic resistance in bacteria, particularly Gram-negative bacilli, has significantly affected the ability of physicians to treat infections, with resultant increased morbidity, mortality, and health care costs. In fact, some strains of bacteria are resistant to all available antibiotics, such as Acinetobacter baumannii, which is the focus of this report. Therefore, the development of new antibiotics active against these resistant strains is urgently needed. In this study, BfmR is further validated as an intriguing target for a novel class of antibiotics. Successful inactivation of BfmR would confer the multiple benefits of a decreased ability of A. baumannii to survive in human body fluids, increased sensitivity to complement-mediated bactericidal activity and, importantly, increased sensitivity to other antibiotics. Structural studies support the potential for this "druggable" target, as they identify the potential for small-molecule binding at functionally relevant sites. Next-phase high-throughput screening studies utilizing BfmR are warranted.
    Language English
    Publishing date 2016-05-11
    Publishing country United States
    Document type Journal Article
    ISSN 2379-5042
    ISSN 2379-5042
    DOI 10.1128/mSphere.00082-16
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: The short-chain oxidoreductase Q9HYA2 from Pseudomonas aeruginosa PAO1 contains an atypical catalytic center.

    Huether, Robert / Mao, Qilong / Duax, William L / Umland, Timothy C

    Protein science : a publication of the Protein Society

    2010  Volume 19, Issue 5, Page(s) 1097–1103

    Abstract: The characteristic oxidation or reduction reaction mechanisms of short-chain oxidoreductase (SCOR) enzymes involve a highly conserved Asp-Ser-Tyr-Lys catalytic tetrad. The SCOR enzyme Q9HYA2 from the pathogenic bacterium Pseudomonas aeruginosa was ... ...

    Abstract The characteristic oxidation or reduction reaction mechanisms of short-chain oxidoreductase (SCOR) enzymes involve a highly conserved Asp-Ser-Tyr-Lys catalytic tetrad. The SCOR enzyme Q9HYA2 from the pathogenic bacterium Pseudomonas aeruginosa was recognized to possess an atypical catalytic tetrad composed of Lys118-Ser146-Thr159-Arg163. Orthologs of Q9HYA2 containing the unusual catalytic tetrad along with conserved substrate and cofactor recognition residues were identified in 27 additional species, the majority of which are bacterial pathogens. However, this atypical catalytic tetrad was not represented within the Protein Data Bank. The crystal structures of unligated and NADPH-complexed Q9HYA2 were determined at 2.3 A resolution. Structural alignment to a polyketide ketoreductase (KR), a typical SCOR, demonstrated that Q9HYA2's Lys118, Ser146, and Arg163 superimposed upon the KR's catalytic Asp114, Ser144, and Lys161, respectively. However, only the backbone of Q9HYA2's Thr159 overlapped KR's catalytic Tyr157. The Thr159 hydroxyl in apo Q9HYA2 is poorly positioned for participating in catalysis. In the Q9HYA2-NADPH complex, the Thr159 side chain was modeled in two alternate rotamers, one of which is positioned to interact with other members of the tetrad and the bound cofactor. A chloride ion is bound at the position normally occupied by the catalytic tyrosine hydroxyl. The putative active site of Q9HYA2 contains a chemical moiety at each catalytically important position of a typical SCOR enzyme. This is the first observation of a SCOR protein with this alternate catalytic center that includes threonine replacing the catalytic tyrosine and an ion replacing the hydroxyl moiety of the catalytic tyrosine.
    MeSH term(s) Amino Acid Sequence ; Bacterial Proteins/chemistry ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Catalytic Domain ; Conserved Sequence ; Crystallography, X-Ray ; Databases, Protein ; Escherichia coli/genetics ; Models, Molecular ; Molecular Sequence Data ; NADP/chemistry ; NADP/metabolism ; Oxidoreductases/chemistry ; Oxidoreductases/genetics ; Oxidoreductases/metabolism ; Protein Binding ; Pseudomonas aeruginosa/enzymology ; Pseudomonas aeruginosa/genetics ; Sequence Alignment
    Chemical Substances Bacterial Proteins ; NADP (53-59-8) ; Oxidoreductases (EC 1.-)
    Language English
    Publishing date 2010-03-27
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 1106283-6
    ISSN 1469-896X ; 0961-8368
    ISSN (online) 1469-896X
    ISSN 0961-8368
    DOI 10.1002/pro.384
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Crystallization and X-ray diffraction analysis of the beta-ketoacyl-acyl carrier protein reductase FabG from Aquifex aeolicus VF5.

    Mao, Qilong / Duax, William L / Umland, Timothy C

    Acta crystallographica. Section F, Structural biology and crystallization communications

    2007  Volume 63, Issue Pt 2, Page(s) 106–109

    Abstract: The gene product of fabG from Aquifex aeolicus has been heterologously expressed in Escherichia coli. Purification of the protein took place using anion-exchange and size-exclusion chromatography and the protein was then crystallized. Diffraction data ... ...

    Abstract The gene product of fabG from Aquifex aeolicus has been heterologously expressed in Escherichia coli. Purification of the protein took place using anion-exchange and size-exclusion chromatography and the protein was then crystallized. Diffraction data were collected to a maximum resolution of 1.8 A and the initial phases were determined by molecular replacement. The A. aeolicus FabG protein is a putative beta-ketoacyl-acyl carrier protein reductase. Structure-function studies of this protein are being performed as part of a larger project investigating naturally occurring deviations from highly conserved residues within the short-chain oxidoreductase (SCOR) family.
    MeSH term(s) Alcohol Oxidoreductases/chemistry ; Alcohol Oxidoreductases/genetics ; Bacteria/enzymology ; Bacteria/genetics ; Bacterial Proteins/chemistry ; Bacterial Proteins/genetics ; Carrier Proteins/chemistry ; Carrier Proteins/genetics ; Cloning, Molecular ; Crystallization ; Crystallography, X-Ray ; Electrophoresis, Polyacrylamide Gel ; Escherichia coli/chemistry ; Escherichia coli/genetics ; Escherichia coli/metabolism
    Chemical Substances Bacterial Proteins ; Carrier Proteins ; Alcohol Oxidoreductases (EC 1.1.-) ; acetoacetyl-CoA reductase (EC 1.1.1.36)
    Language English
    Publishing date 2007-01-17
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ISSN 1744-3091
    ISSN (online) 1744-3091
    DOI 10.1107/S1744309107000103
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Structure of shikimate kinase, an in vivo essential metabolic enzyme in the nosocomial pathogen Acinetobacter baumannii, in complex with shikimate.

    Sutton, Kristin A / Breen, Jennifer / MacDonald, Ulrike / Beanan, Janet M / Olson, Ruth / Russo, Thomas A / Schultz, L Wayne / Umland, Timothy C

    Acta crystallographica. Section D, Biological crystallography

    2015  Volume 71, Issue Pt 8, Page(s) 1736–1744

    Abstract: Acinetobacter baumannii is an opportunistic Gram-negative pathogen that is an important cause of healthcare-associated infections exhibiting high mortality rates. Clinical isolates of multidrug-resistant (MDR) and extremely drug-resistant (XDR) A. ... ...

    Abstract Acinetobacter baumannii is an opportunistic Gram-negative pathogen that is an important cause of healthcare-associated infections exhibiting high mortality rates. Clinical isolates of multidrug-resistant (MDR) and extremely drug-resistant (XDR) A. baumannii strains are increasingly being observed. Compounding this concern is the dearth of new antibacterial agents in late-stage development that are effective against MDR and XDR A. baumannii. As part of an effort to address these concerns, two genes (aroA and aroC) of the shikimate pathway have previously been determined to be essential for the growth and survival of A. baumannii during host infection (i.e. to be essential in vivo). This study expands upon these results by demonstrating that the A. baumannii aroK gene, encoding shikimate kinase (SK), is also essential in vivo in a rat soft-tissue infection model. The crystal structure of A. baumannii SK in complex with the substrate shikimate and a sulfate ion that mimics the binding interactions expected for the β-phosphate of ATP was then determined to 1.91 Å resolution and the enzyme kinetics were characterized. The flexible shikimate-binding domain and LID region are compared with the analogous regions in other SK crystal structures. The impact of structural differences and sequence divergence between SKs from pathogenic bacteria that may influence antibiotic-development efforts is discussed.
    MeSH term(s) Acinetobacter Infections/metabolism ; Acinetobacter Infections/microbiology ; Acinetobacter baumannii/chemistry ; Acinetobacter baumannii/enzymology ; Acinetobacter baumannii/growth & development ; Acinetobacter baumannii/metabolism ; Animals ; Crystallography, X-Ray ; Humans ; Models, Molecular ; Phosphotransferases (Alcohol Group Acceptor)/chemistry ; Phosphotransferases (Alcohol Group Acceptor)/metabolism ; Protein Conformation ; Rats ; Shikimic Acid/metabolism ; Signal Transduction
    Chemical Substances Shikimic Acid (29MS2WI2NU) ; Phosphotransferases (Alcohol Group Acceptor) (EC 2.7.1.-) ; shikimate kinase (EC 2.7.1.71)
    Language English
    Publishing date 2015-08
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2020492-9
    ISSN 1399-0047 ; 2059-7983 ; 0907-4449
    ISSN (online) 1399-0047 ; 2059-7983
    ISSN 0907-4449
    DOI 10.1107/S139900471501189X
    Database MEDical Literature Analysis and Retrieval System OnLINE

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