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  1. Article ; Online: Aerosolized delivery of ESKAPE pathogens for murine pneumonia models.

    Rox, Katharina / Medina, Eva

    Scientific reports

    2024  Volume 14, Issue 1, Page(s) 2558

    Abstract: Murine pneumonia models for ESKAPE pathogens serve to evaluate novel antibacterials or to investigate immunological responses. The majority of published models uses intranasal or to a limited extent the intratracheal instillation to challenge animals. In ...

    Abstract Murine pneumonia models for ESKAPE pathogens serve to evaluate novel antibacterials or to investigate immunological responses. The majority of published models uses intranasal or to a limited extent the intratracheal instillation to challenge animals. In this study, we propose the aerosol delivery of pathogens using a nebulizer. Aerosol delivery typically results in homogeneous distribution of the inoculum in the lungs because of lower particle size. This is of particular importance when compounds are assessed for their pharmacokinetic and pharmacodynamic (PK/PD) relationships as it allows to conduct several analysis with the same sample material. Moreover, aerosol delivery has the advantage that it mimics the 'natural route' of respiratory infection. In this short and concise study, we show that aerosol delivery of pathogens resulted in a sustained bacterial burden in the neutropenic lung infection model for five pathogens tested, whereas it gave a similar result in immunocompetent mice for three out of five pathogens. Moreover, a substantial bacterial burden in the lungs was already achieved 2 h post inhalation. Hence, this study constitutes a viable alternative for intranasal administration and a refinement of murine pneumonia models for PK/PD assessments of novel antibacterial compounds allowing to study multiple readouts with the same sample material.
    MeSH term(s) Animals ; Mice ; Respiratory Aerosols and Droplets ; Administration, Inhalation ; Lung ; Pneumonia/drug therapy ; Anti-Bacterial Agents/therapeutic use ; Anti-Bacterial Agents/pharmacokinetics
    Chemical Substances Anti-Bacterial Agents
    Language English
    Publishing date 2024-01-31
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-024-52958-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article: All Roads Lead to Rome: Enhancing the Probability of Target Attainment with Different Pharmacokinetic/Pharmacodynamic Modelling Approaches.

    Khalid, Kashaf / Rox, Katharina

    Antibiotics (Basel, Switzerland)

    2023  Volume 12, Issue 4

    Abstract: In light of rising antimicrobial resistance and a decreasing number of antibiotics with novel modes of action, it is of utmost importance to accelerate development of novel treatment options. One aspect of acceleration is to understand pharmacokinetics ( ... ...

    Abstract In light of rising antimicrobial resistance and a decreasing number of antibiotics with novel modes of action, it is of utmost importance to accelerate development of novel treatment options. One aspect of acceleration is to understand pharmacokinetics (PK) and pharmacodynamics (PD) of drugs and to assess the probability of target attainment (PTA). Several in vitro and in vivo methods are deployed to determine these parameters, such as time-kill-curves, hollow-fiber infection models or animal models. However, to date the use of in silico methods to predict PK/PD and PTA is increasing. Since there is not just one way to perform the in silico analysis, we embarked on reviewing for which indications and how PK and PK/PD models as well as PTA analysis has been used to contribute to the understanding of the PK and PD of a drug. Therefore, we examined four recent examples in more detail, namely ceftazidime-avibactam, omadacycline, gepotidacin and zoliflodacin as well as cefiderocol. Whereas the first two compound classes mainly relied on the 'classical' development path and PK/PD was only deployed after approval, cefiderocol highly profited from in silico techniques that led to its approval. Finally, this review shall highlight current developments and possibilities to accelerate drug development, especially for anti-infectives.
    Language English
    Publishing date 2023-04-01
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2681345-2
    ISSN 2079-6382
    ISSN 2079-6382
    DOI 10.3390/antibiotics12040690
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Lectin-Targeted Prodrugs Activated by

    Meiers, Joscha / Rox, Katharina / Titz, Alexander

    Journal of medicinal chemistry

    2022  Volume 65, Issue 20, Page(s) 13988–14014

    Abstract: ... ...

    Abstract Chronic
    MeSH term(s) Humans ; Pseudomonas aeruginosa ; Lectins/pharmacology ; Lectins/metabolism ; Anti-Bacterial Agents/pharmacology ; Anti-Bacterial Agents/metabolism ; Prodrugs/pharmacology ; Prodrugs/metabolism ; Biofilms ; Pseudomonas Infections/drug therapy ; Virulence Factors/metabolism ; Fluoroquinolones/pharmacology
    Chemical Substances Lectins ; Anti-Bacterial Agents ; Prodrugs ; Virulence Factors ; Fluoroquinolones
    Language English
    Publishing date 2022-10-06
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218133-2
    ISSN 1520-4804 ; 0022-2623
    ISSN (online) 1520-4804
    ISSN 0022-2623
    DOI 10.1021/acs.jmedchem.2c01214
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Synthesis and Characterization of DOTAM-Based Sideromycins for Bacterial Imaging and Antimicrobial Therapy.

    Peukert, Carsten / Rox, Katharina / Karge, Bianka / Hotop, Sven-Kevin / Brönstrup, Mark

    ACS infectious diseases

    2023  Volume 9, Issue 2, Page(s) 330–341

    Abstract: The rise of antimicrobial resistance, especially in Gram-negative bacteria, calls for novel diagnostics and antibiotics. To efficiently penetrate their double-layered cell membrane, we conjugated the potent antibiotics daptomycin, vancomycin, and ... ...

    Abstract The rise of antimicrobial resistance, especially in Gram-negative bacteria, calls for novel diagnostics and antibiotics. To efficiently penetrate their double-layered cell membrane, we conjugated the potent antibiotics daptomycin, vancomycin, and sorangicin A to catechol siderophores, which are actively internalized by the bacterial iron uptake machinery. LC-MS/MS uptake measurements of sorangicin derivatives verified that the conjugation led to a 100- to 525-fold enhanced uptake into bacteria compared to the free drug. However, the transfer to the cytosol was insufficient, which explains their lack of antibiotic efficacy. Potent antimicrobial effects were observed for the daptomycin conjugate
    MeSH term(s) Humans ; Daptomycin/chemistry ; Chromatography, Liquid ; Tandem Mass Spectrometry ; Anti-Bacterial Agents/chemistry ; Bacteria/metabolism
    Chemical Substances Daptomycin (NWQ5N31VKK) ; sideromycins (56509-18-3) ; Anti-Bacterial Agents
    Language English
    Publishing date 2023-01-31
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2373-8227
    ISSN (online) 2373-8227
    DOI 10.1021/acsinfecdis.2c00523
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Discovery of

    Mała, Patrycja / Siebs, Eike / Meiers, Joscha / Rox, Katharina / Varrot, Annabelle / Imberty, Anne / Titz, Alexander

    Journal of medicinal chemistry

    2022  Volume 65, Issue 20, Page(s) 14180–14200

    Abstract: The Gram-negative ... ...

    Abstract The Gram-negative pathogen
    MeSH term(s) Humans ; Mice ; Animals ; Pseudomonas aeruginosa/metabolism ; Lectins/metabolism ; Ligands ; Amides/pharmacology ; Amides/metabolism ; Anti-Bacterial Agents/pharmacology ; Anti-Bacterial Agents/metabolism ; Sulfonamides/metabolism ; Thiourea/metabolism ; Biofilms
    Chemical Substances Lectins ; Ligands ; Amides ; Anti-Bacterial Agents ; Sulfonamides ; Thiourea (GYV9AM2QAG)
    Language English
    Publishing date 2022-10-18
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218133-2
    ISSN 1520-4804 ; 0022-2623
    ISSN (online) 1520-4804
    ISSN 0022-2623
    DOI 10.1021/acs.jmedchem.2c01373
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: A simplified LC-MS/MS method for the quantification of the cardiovascular disease biomarker trimethylamine-

    Rox, Katharina / Rath, Silke / Pieper, Dietmar H / Vital, Marius / Brönstrup, Mark

    Journal of pharmaceutical analysis

    2021  Volume 11, Issue 4, Page(s) 523–528

    Abstract: Trimethylamine- ...

    Abstract Trimethylamine-
    Language English
    Publishing date 2021-03-26
    Publishing country China
    Document type Journal Article
    ZDB-ID 2630174-X
    ISSN 2214-0883 ; 2095-1779
    ISSN (online) 2214-0883
    ISSN 2095-1779
    DOI 10.1016/j.jpha.2021.03.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Neutralizing the Impact of the Virulence Factor LecA from Pseudomonas aeruginosa on Human Cells with New Glycomimetic Inhibitors.

    Zahorska, Eva / Rosato, Francesca / Stober, Kai / Kuhaudomlarp, Sakonwan / Meiers, Joscha / Hauck, Dirk / Reith, Dorina / Gillon, Emilie / Rox, Katharina / Imberty, Anne / Römer, Winfried / Titz, Alexander

    Angewandte Chemie (International ed. in English)

    2023  Volume 62, Issue 7, Page(s) e202215535

    Abstract: Bacterial adhesion, biofilm formation and host cell invasion of the ESKAPE pathogen Pseudomonas aeruginosa require the tetravalent lectins LecA and LecB, which are therefore drug targets to fight these infections. Recently, we have reported highly potent ...

    Abstract Bacterial adhesion, biofilm formation and host cell invasion of the ESKAPE pathogen Pseudomonas aeruginosa require the tetravalent lectins LecA and LecB, which are therefore drug targets to fight these infections. Recently, we have reported highly potent divalent galactosides as specific LecA inhibitors. However, they suffered from very low solubility and an intrinsic chemical instability due to two acylhydrazone motifs, which precluded further biological evaluation. Here, we isosterically substituted the acylhydrazones and systematically varied linker identity and length between the two galactosides necessary for LecA binding. The optimized divalent LecA ligands showed improved stability and were up to 1000-fold more soluble. Importantly, these properties now enabled their biological characterization. The lead compound L2 potently inhibited LecA binding to lung epithelial cells, restored wound closure in a scratch assay and reduced the invasiveness of P. aeruginosa into host cells.
    MeSH term(s) Humans ; Adhesins, Bacterial/chemistry ; Pseudomonas aeruginosa/metabolism ; Virulence Factors/metabolism ; Galactosides/chemistry ; Galactosides/metabolism ; Galactosides/pharmacology ; Bacterial Adhesion
    Chemical Substances Adhesins, Bacterial ; Virulence Factors ; Galactosides
    Language English
    Publishing date 2023-01-10
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202215535
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: X-ray Structure of Main Protease of the Novel Coronavirus SARS-CoV-2 Enables Design of α-Ketoamide Inhibitors

    Zhang, Linlin / Lin, Daizong / Sun, Xinyuanyuan / Rox, Katharina / Hilgenfeld, Rolf

    bioRxiv

    Abstract: A novel coronavirus has been identified as the causative agent of a massive outbreak of atypical pneumonia originating at Wuhan, Hubei province, China. Involved in the formation of the coronavirus replication complex, the viral main protease (Mpro, also ... ...

    Abstract A novel coronavirus has been identified as the causative agent of a massive outbreak of atypical pneumonia originating at Wuhan, Hubei province, China. Involved in the formation of the coronavirus replication complex, the viral main protease (Mpro, also called 3CLpro) represents an attractive target for therapy. We determined the crystal structure of the unliganded Mpro at 1.75 Å resolution and used this structure to guide optimization of a series of alpha-ketoamide inhibitors. The main goal of the optimization efforts was improvement of the pharmacokinetic properties of the compounds. We further describe 1.95- and 2.20-Å crystal structures of the complex between the enzyme and the most potent alpha-ketoamide optimized this way. These structures will form the basis for further development of these compounds to antiviral drugs.
    Keywords covid19
    Publisher BioRxiv; MedRxiv; WHO
    Document type Article ; Online
    DOI 10.1101/2020.02.17.952879
    Database COVID19

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  9. Article ; Online: X-ray Structure of Main Protease of the Novel Coronavirus SARS-CoV-2 Enables Design of α-Ketoamide Inhibitors

    Zhang, Linlin / Lin, Daizong / Sun, Xinyuanyuan / Rox, Katharina / Hilgenfeld, Rolf

    bioRxiv

    Keywords covid19
    Language English
    Publishing date 2020-02-20
    Publisher Cold Spring Harbor Laboratory
    Document type Article ; Online
    DOI 10.1101/2020.02.17.952879
    Database COVID19

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  10. Article ; Online: A simplified LC-MS/MS method for the quantification of the cardiovascular disease biomarker trimethylamine-N-oxide and its precursors

    Rox, Katharina / Rath, Silke / Pieper, Dietmar H. / Vital, Marius / Brönstrup, Mark

    Journal of Pharmaceutical Analysis

    2021  

    Abstract: Trimethylamine-N-oxide (TMAO) has emerged as a potential biomarker for atherosclerosis and the development of cardiovascular diseases (CVDs). Although several clinical studies have shown striking associations of TMAO levels with atherosclerosis and CVDs, ...

    Abstract Trimethylamine-N-oxide (TMAO) has emerged as a potential biomarker for atherosclerosis and the development of cardiovascular diseases (CVDs). Although several clinical studies have shown striking associations of TMAO levels with atherosclerosis and CVDs, TMAO determinations are not clinical routine yet. The current methodology relies on isotope-labeled internal standards, which adds to pre-analytical complexity and costs for the quantification of TMAO and its precursors carnitine, betaine or choline. Here, we report a liquid chromatography-tandem mass spectrometry based method that is fast (throughput up to 240 samples/day), consumes low sample volumes (e.g., from a finger prick), and does not require isotope-labeled standards. We circumvented the analytical problem posed by the presence of endogenous TMAO and its precursors in human plasma by using an artificial plasma matrix for calibration. We cross-validated the results obtained using an artificial matrix with those using mouse plasma matrix and demonstrated that TMAO, carnitine, betaine and choline were accurately quantified in ‘real-life’ human plasma samples from healthy volunteers, obtained either from a finger prick or from venous puncture. Additionally, we assessed the stability of samples stored at −20 °C and room temperature. Whereas all metabolites were stable at −20 °C, increasing concentrations of choline were determined when stored at room temperature. Our method will facilitate the establishment of TMAO as a routine clinical biomarker in hematology in order to assess the risk for CVDs development, or to monitor disease progression and intervention effects.

    German Centre for Infection Research
    Keywords Analytical Chemistry ; Electrochemistry ; Spectroscopy ; Drug Discovery ; Pharmaceutical Science ; Pharmacy
    Subject code 610
    Language English
    Publisher Elsevier BV
    Publishing country de
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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