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Gabriele Sass
California Institute for Medical Research, San Jose, CA

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Article
Published: 12 July 2021 in Antimicrobial Agents and Chemotherapy
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Introduction. Nikkomycin Z (nikZ) is a chitin synthase inhibitor. Efficacy against Coccidioides has been demonstrated in animal models of pulmonary or brain infection. Its short half-life, in mice and humans, would necessitate divided daily dosing. We assayed nikZ efficacy in disseminated coccidioidomycosis (in a reduction of CFU design), and whether sustained release might be useful. Methods. Mice were challenged intravenously, with low or high arthroconidial inocula. Fluconazole, clinically the most commonly used anti-coccidioidal drug, was compared (gavage) at high dose to a dose range of nikZ administered intraperitoneally or, to mimic sustained release, administered continuously in drinking water. Therapy was given for 5 days. Results. In vitro, both fluconazole and nikZ inhibited the isolate studied; nikZ was fungicidal. Oral nikZ therapy gave similar results to intraperitoneal nikZ, and sterilized infection in most animals after low inoculum challenge. In both challenges, oral nikZ produced greater reduction of CFU in organs (lung, liver, spleen) than fluconazole. Oral nikZ doses ≥200 mg/kg/day were particularly effective, in all organs, and were well tolerated. This efficacy occurred even though, after severe challenge, mice had reduced water intake, resulting in ingesting less than the desired dose, particularly initially after infection. Summary . This study shows, for the first time, efficacy of nikZ against disseminated coccidioidomycosis. Efficacy was shown after challenges producing different levels of severity of disease. This study also suggests the likely benefits of developing an extended release formulation, supplying continuous systemic concentrations of nikZ.

ACS Style

Gabriele Sass; David J. Larwood; Marife Martinez; Paulami Chatterjee; Melissa O. Xavier; David A. Stevens. NIKKOMYCIN Z AGAINST DISSEMINATED COCCIDIOIDOMYCOSIS IN A MURINE MODEL OF SUSTAINED RELEASE DOSING. Antimicrobial Agents and Chemotherapy 2021, 1 .

AMA Style

Gabriele Sass, David J. Larwood, Marife Martinez, Paulami Chatterjee, Melissa O. Xavier, David A. Stevens. NIKKOMYCIN Z AGAINST DISSEMINATED COCCIDIOIDOMYCOSIS IN A MURINE MODEL OF SUSTAINED RELEASE DOSING. Antimicrobial Agents and Chemotherapy. 2021; ():1.

Chicago/Turabian Style

Gabriele Sass; David J. Larwood; Marife Martinez; Paulami Chatterjee; Melissa O. Xavier; David A. Stevens. 2021. "NIKKOMYCIN Z AGAINST DISSEMINATED COCCIDIOIDOMYCOSIS IN A MURINE MODEL OF SUSTAINED RELEASE DOSING." Antimicrobial Agents and Chemotherapy , no. : 1.

Journal article
Published: 28 April 2021 in Journal of Fungi
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The Pseudomonas quinolone signal (PQS) is an important quorum-sensing molecule for Pseudomonas aeruginosa that regulates virulence factors, chelates iron, and is an important factor in interactions with eukaryotes, including fungi and mammalian hosts. It was previously shown to inhibit or boost Aspergillus, depending on the milieu iron concentration. We studied several molecular modifications of the PQS molecule, and their effects on Aspergillus biofilm metabolism and growth in vitro, and the effects of iron supplementation. We found that most molecules inhibited Aspergillus at concentrations similar to that of PQS, but with relatively flat dose-responses, and all were less potent than PQS. The inhibition was reversible by iron, suggesting interference with fungal iron metabolism. Stimulation of Aspergillus was not noted. We conclude that the critical Aspergillus-inhibiting moeities of the PQS molecule were partially, but not completely, interfered with by molecular modifications at several sites on the PQS molecule. The mechanism, as with PQS, appears to relate to fungal iron metabolism.

ACS Style

Hasan Nazik; Gabriele Sass; Paul Williams; Eric Déziel; David Stevens. Molecular Modifications of the Pseudomonas Quinolone Signal in the Intermicrobial Competition with Aspergillus. Journal of Fungi 2021, 7, 343 .

AMA Style

Hasan Nazik, Gabriele Sass, Paul Williams, Eric Déziel, David Stevens. Molecular Modifications of the Pseudomonas Quinolone Signal in the Intermicrobial Competition with Aspergillus. Journal of Fungi. 2021; 7 (5):343.

Chicago/Turabian Style

Hasan Nazik; Gabriele Sass; Paul Williams; Eric Déziel; David Stevens. 2021. "Molecular Modifications of the Pseudomonas Quinolone Signal in the Intermicrobial Competition with Aspergillus." Journal of Fungi 7, no. 5: 343.

Journal article
Published: 26 April 2021 in Pathogens
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Pseudomonas aeruginosa and Aspergillus fumigatus are pathogens that are associated with deterioration of lung function, e.g., in persons with cystic fibrosis (CF). There is evidence that co-infections with these pathogens cause airway inflammation and aggravate pathology in CF lungs. Intermicrobial competition of P. aeruginosa and A. fumigatus has been described, but it is unknown how anti-fungal therapy is affected. The anti-fungal azole voriconazole (VCZ), supernatants of P. aeruginosa laboratory isolates PA14 or PAO1, or clinical isolate Pa10 independently inhibited biofilm metabolism of A. fumigatus isolates 10AF and AF13073. When VCZ and supernatants were combined at their IC50s, synergistic effects on A. fumigatus were found. Synergistic effects were no longer observed when P. aeruginosa supernatants were prepared in the presence of iron, or when P. aeruginosa mutants were lacking the ability to produce pyoverdine and pyochelin. Combination of pure P. aeruginosa products pyoverdine, pyochelin, and pyocyanin with VCZ showed synergistic anti-fungal effects. Combining VCZ with P. aeruginosa supernatants also improved its MIC and MFC against planktonic A. fumigatus. In summary, in the case of P. aeruginosa–A. fumigatus co-infections, it appeared that the P. aeruginosa co-infection facilitated therapy of the Aspergillus; lower concentrations of VCZ might be sufficient to control fungal growth.

ACS Style

Gabriele Sass; Pallabi Shrestha; David Stevens. Pseudomonas aeruginosa Virulence Factors Support Voriconazole Effects on Aspergillus fumigatus. Pathogens 2021, 10, 519 .

AMA Style

Gabriele Sass, Pallabi Shrestha, David Stevens. Pseudomonas aeruginosa Virulence Factors Support Voriconazole Effects on Aspergillus fumigatus. Pathogens. 2021; 10 (5):519.

Chicago/Turabian Style

Gabriele Sass; Pallabi Shrestha; David Stevens. 2021. "Pseudomonas aeruginosa Virulence Factors Support Voriconazole Effects on Aspergillus fumigatus." Pathogens 10, no. 5: 519.

Journal article
Published: 16 April 2021 in Viruses
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Aspergillus and Pseudomonas compete in nature, and are the commonest bacterial and fungal pathogens in some clinical settings, such as the cystic fibrosis lung. Virus infections of fungi occur naturally. Effects on fungal physiology need delineation. A common reference Aspergillus fumigatus strain, long studied in two (of many) laboratories, was found infected with the AfuPmV-1 virus. One isolate was cured of virus, producing a virus-free strain. Virus from the infected strain was purified and used to re-infect three subcultures of the virus-free fungus, producing six fungal strains, otherwise isogenic. They were studied in intermicrobial competition with Pseudomonas aeruginosa. Pseudomonas culture filtrates inhibited forming or preformed Aspergillus biofilm from infected strains to a greater extent, also seen when Pseudomonas volatiles were assayed on Aspergillus. Purified iron-chelating Pseudomonas molecules, known inhibitors of Aspergillus biofilm, reproduced these differences. Iron, a stimulus of Aspergillus, enhanced the virus-free fungus, compared to infected. All infected fungal strains behaved similarly in assays. We show an important consequence of virus infection, a weakening in intermicrobial competition. Viral infection may affect the outcome of bacterial–fungal competition in nature and patients. We suggest that this occurs via alteration in fungal stress responses, the mechanism best delineated here is a result of virus-induced altered Aspergillus iron metabolism.

ACS Style

Hasan Nazik; Ioly Kotta-Loizou; Gabriele Sass; Robert Coutts; David Stevens. Virus Infection of Aspergillus fumigatus Compromises the Fungus in Intermicrobial Competition. Viruses 2021, 13, 686 .

AMA Style

Hasan Nazik, Ioly Kotta-Loizou, Gabriele Sass, Robert Coutts, David Stevens. Virus Infection of Aspergillus fumigatus Compromises the Fungus in Intermicrobial Competition. Viruses. 2021; 13 (4):686.

Chicago/Turabian Style

Hasan Nazik; Ioly Kotta-Loizou; Gabriele Sass; Robert Coutts; David Stevens. 2021. "Virus Infection of Aspergillus fumigatus Compromises the Fungus in Intermicrobial Competition." Viruses 13, no. 4: 686.

Journal article
Published: 04 August 2020 in Journal of Fungi
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Meningitis is the most devastating form of coccidioidomycosis. A convenient, rapid diagnostic method could result in early treatment and avoid many meningitis complications. We studied cerebrospinal fluid (CSF) samples in patients with documented coccidioidal meningitis, and controls, with complement fixation (CF), immunodiffusion (ID) (the “classical” assays), lateral flow assays (LFA; one-strip and two-strip), and two enzyme immunoassays (EIA). The two-strip LFA and EIAs not only enabled separate testing for IgG and IgM antibodies separately, but also could aggregate results for each method. CF with ID or the aggregate use of IgG and IgM tests were considered optimal test uses. LFAs and EIAs were evaluated at 1:21 and 1:441 dilutions of specimens. All assays were compared to true patient status. With 49 patient specimens and 40 controls, this is the largest comparative study of CSF coccidioidal diagnostics. Sensitivity of these tests ranged from 71–95% and specificity 90–100%. IgM assays were less sensitive. Assays at 1:441 were similarly specific but less sensitive, suggesting that serial dilutions of samples could result in assays yielding titers. Agreement of positive results on cases was 87–100%. When kits are available, hospital laboratories in endemic areas can perform testing. LFA assays do not require a laboratory, are simple to use, and give rapid results, potentially even at the bedside.

ACS Style

David A. Stevens; Marife Martinez; Gabriele Sass; Demosthenes Pappagianis; Brian Doherty; Hannah Kutsche; Meredith McGuire. Comparative Study of Newer and Established Methods of Diagnosing Coccidioidal Meningitis. Journal of Fungi 2020, 6, 125 .

AMA Style

David A. Stevens, Marife Martinez, Gabriele Sass, Demosthenes Pappagianis, Brian Doherty, Hannah Kutsche, Meredith McGuire. Comparative Study of Newer and Established Methods of Diagnosing Coccidioidal Meningitis. Journal of Fungi. 2020; 6 (3):125.

Chicago/Turabian Style

David A. Stevens; Marife Martinez; Gabriele Sass; Demosthenes Pappagianis; Brian Doherty; Hannah Kutsche; Meredith McGuire. 2020. "Comparative Study of Newer and Established Methods of Diagnosing Coccidioidal Meningitis." Journal of Fungi 6, no. 3: 125.

Journal article
Published: 25 July 2020 in Journal of Fungi
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Background: Pseudomonas aeruginosa (Pa) and Aspergillus fumigatus (Af) compete with each other for nutrients and survival in natural environments, and have been extensively studied because of their intermicrobial interactions in the human microbiome. These are the principal microbes infecting immunocompromised patients and persons with cystic fibrosis, particularly the airways. These intermicrobial studies have largely been conducted in liquid medium or on agar, and thus focus on soluble or diffusible microbial products. Several key inhibitory molecules were defined in such studies. Methods: in the present report, we examine several methodologies which can be conveniently used to study the interaction of microbial volatiles, including capture methods and kinetics. Results: Pa volatiles inhibit Af, and the inhibitory mechanism appears to be the incorporation of the inhibitory molecules into the substrate nourishing the Af, rather than directly onto Af structures. We define by mass spectroscopy some specific volatile Pa products that can inhibit Af. Some of these molecules are selected for interest by the study of gene deletion mutants, producing a few Pa strains that were impaired in inhibition. We presumed the volatiles of these latter strains could be excluded from the search for inhibitors. Conclusion: the Pa inhibition of Af via a gaseous phase could be critical components in their competition, particularly in airways, where more direct contact may not be extensive.

ACS Style

Hasan Nazik; Gabriele Sass; Eric Déziel; David A. Stevens. Aspergillus Is Inhibited by Pseudomonas aeruginosa Volatiles. Journal of Fungi 2020, 6, 118 .

AMA Style

Hasan Nazik, Gabriele Sass, Eric Déziel, David A. Stevens. Aspergillus Is Inhibited by Pseudomonas aeruginosa Volatiles. Journal of Fungi. 2020; 6 (3):118.

Chicago/Turabian Style

Hasan Nazik; Gabriele Sass; Eric Déziel; David A. Stevens. 2020. "Aspergillus Is Inhibited by Pseudomonas aeruginosa Volatiles." Journal of Fungi 6, no. 3: 118.

Review
Published: 06 June 2020 in Journal of Fungi
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Pseudomonas aeruginosa is one of the most prominent opportunistic bacteria in airways of cystic fibrosis patients and in immunocompromised patients. These bacteria share the same polymicrobial niche with other microbes, such as the opportunistic fungus Aspergillus fumigatus. Their inter-kingdom interactions and diverse exchange of secreted metabolites are responsible for how they both fare in competition for ecological niches. The outcomes of their contests likely determine persistent damage and degeneration of lung function. With a myriad of virulence factors and metabolites of promising antifungal activity, P. aeruginosa products or their derivatives may prove useful in prophylaxis and therapy against A. fumigatus. Quorum sensing underlies the primary virulence strategy of P. aeruginosa, which serves as cell–cell communication and ultimately leads to the production of multiple virulence factors. Understanding the quorum-sensing-related pathogenic mechanisms of P. aeruginosa is a first step for understanding intermicrobial competition. In this review, we provide a basic overview of some of the central virulence factors of P. aeruginosa that are regulated by quorum-sensing response pathways and briefly discuss the hitherto known antifungal properties of these virulence factors. This review also addresses the role of the bacterial secretion machinery regarding virulence factor secretion and maintenance of cell–cell communication.

ACS Style

Paulami Chatterjee; Gabriele Sass; Wieslaw Swietnicki; David A. Stevens. Review of Potential Pseudomonas Weaponry, Relevant to the Pseudomonas–Aspergillus Interplay, for the Mycology Community. Journal of Fungi 2020, 6, 81 .

AMA Style

Paulami Chatterjee, Gabriele Sass, Wieslaw Swietnicki, David A. Stevens. Review of Potential Pseudomonas Weaponry, Relevant to the Pseudomonas–Aspergillus Interplay, for the Mycology Community. Journal of Fungi. 2020; 6 (2):81.

Chicago/Turabian Style

Paulami Chatterjee; Gabriele Sass; Wieslaw Swietnicki; David A. Stevens. 2020. "Review of Potential Pseudomonas Weaponry, Relevant to the Pseudomonas–Aspergillus Interplay, for the Mycology Community." Journal of Fungi 6, no. 2: 81.

Journal article
Published: 07 August 2019 in The American Journal of Tropical Medicine and Hygiene
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Trypanosoma cruzi is the etiologic agent of Chagas disease (CD), which can result in severe cardiomyopathy. Trypanosoma cruzi is endemic to the Americas, and of particular importance in Latin America. In the United States and other non-endemic countries, rising case numbers have also been observed. The currently used drugs are benznidazole (BNZ) and nifurtimox, which have limited efficacy during chronic infection. We repurposed itraconazole (ICZ), originally an antifungal, in combination with amiodarone (AMD), an antiarrhythmic, with the goal of interfering with T. cruzi infection. Human pluripotent stem cells (hiPSCs) were differentiated into cardiomyocytes (hiPSC-CMs). Vero cells or hiPSC-CMs were infected with T. cruzi trypomastigotes of the II or I strain in the presence of ICZ and/or AMD. After 48 hours, cells were Giemsa stained, and infection and multiplication were evaluated microscopically. Trypanosoma cruzi infection and multiplication were evalutated also by electron microscopy. BNZ was used as a reference compound. Cell metabolism in the presence of test substances was assessed. Itraconazole and AMD showed strain- and dose-dependent interference with T. cruzi infection and multiplication in Vero cells or hiPSC-CMs. Combinations of ICZ and AMD were more effective against T. cruzi than the single substances, or BNZ, without affecting host cell metabolism, and better preserving host cell integrity during infection. Our in vitro data in hiPSC-CMs suggest that a combination of ICZ and AMD might serve as a treatment option for CD in patients, but that different responses due to T. cruzi strain differences have to be taken into account.

ACS Style

Gabriele Sass; Roy T. Madigan; Lydia-Marie Joubert; Adriana Bozzi; Nazish Sayed; Joseph C. Wu; David A. Stevens. A Combination of Itraconazole and Amiodarone Is Highly Effective against Trypanosoma cruzi Infection of Human Stem Cell–Derived Cardiomyocytes. The American Journal of Tropical Medicine and Hygiene 2019, 101, 383 -391.

AMA Style

Gabriele Sass, Roy T. Madigan, Lydia-Marie Joubert, Adriana Bozzi, Nazish Sayed, Joseph C. Wu, David A. Stevens. A Combination of Itraconazole and Amiodarone Is Highly Effective against Trypanosoma cruzi Infection of Human Stem Cell–Derived Cardiomyocytes. The American Journal of Tropical Medicine and Hygiene. 2019; 101 (2):383-391.

Chicago/Turabian Style

Gabriele Sass; Roy T. Madigan; Lydia-Marie Joubert; Adriana Bozzi; Nazish Sayed; Joseph C. Wu; David A. Stevens. 2019. "A Combination of Itraconazole and Amiodarone Is Highly Effective against Trypanosoma cruzi Infection of Human Stem Cell–Derived Cardiomyocytes." The American Journal of Tropical Medicine and Hygiene 101, no. 2: 383-391.

Research article
Published: 08 May 2019 in PLoS ONE
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Pseudomonas aeruginosa and Aspergillus fumigatus are pathogens frequently co-inhabiting immunocompromised patient airways, particularly in people with cystic fibrosis. Both microbes depend on the availability of iron, and compete for iron in their microenvironment. We showed previously that the P. aeruginosa siderophore pyoverdine is the main instrument in battling A. fumigatus biofilms, by iron chelation and denial of iron to the fungus. Here we show that A. fumigatus siderophores defend against anti-fungal P. aeruginosa effects. P. aeruginosa supernatants produced in the presence of wildtype A. fumigatus planktonic supernatants (Afsup) showed less activity against A. fumigatus biofilms than P. aeruginosa supernatants without Afsup, despite higher production of pyoverdine by P. aeruginosa. Supernatants of A. fumigatus cultures lacking the sidA gene (AfΔsidA), unable to produce hydroxamate siderophores, were less capable of protecting A. fumigatus biofilms from P. aeruginosa supernatants and pyoverdine. AfΔsidA biofilm was more sensitive towards inhibitory effects of pyoverdine, the iron chelator deferiprone (DFP), or amphothericin B than wildtype A. fumigatus biofilm. Supplementation of sidA-deficient A. fumigatus biofilm with A. fumigatus siderophores restored resistance to pyoverdine. The A. fumigatus siderophore production inhibitor celastrol sensitized wildtype A. fumigatus biofilms towards the anti-fungal activity of DFP. In conclusion, A. fumigatus hydroxamate siderophores play a pivotal role in A. fumigatus competition for iron against P. aeruginosa.

ACS Style

Gabriele Sass; Shajia R. Ansari; Anna-Maria Dietl; Eric Déziel; Hubertus Haas; David A. Stevens. Intermicrobial interaction: Aspergillus fumigatus siderophores protect against competition by Pseudomonas aeruginosa. PLoS ONE 2019, 14, e0216085 .

AMA Style

Gabriele Sass, Shajia R. Ansari, Anna-Maria Dietl, Eric Déziel, Hubertus Haas, David A. Stevens. Intermicrobial interaction: Aspergillus fumigatus siderophores protect against competition by Pseudomonas aeruginosa. PLoS ONE. 2019; 14 (5):e0216085.

Chicago/Turabian Style

Gabriele Sass; Shajia R. Ansari; Anna-Maria Dietl; Eric Déziel; Hubertus Haas; David A. Stevens. 2019. "Intermicrobial interaction: Aspergillus fumigatus siderophores protect against competition by Pseudomonas aeruginosa." PLoS ONE 14, no. 5: e0216085.

Journal article
Published: 01 November 2017 in Microbiology
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Pseudomonas aeruginosa (Pa) and Candida albicans (Ca) are major bacterial and fungal pathogens in immunocompromised hosts, and notably in the airways of cystic fibrosis patients. The bacteriophages of Pa physically alter biofilms, and were recently shown to inhibit the biofilms of Aspergillus fumigatus. To understand the range of this viral–fungal interaction, we studied Pa phages Pf4 and Pf1, and their interactions with Ca biofilm formation and preformed Ca biofilm. Both forms of Ca biofilm development, as well as planktonic Ca growth, were inhibited by either phage. The inhibition of biofilm was reversed by the addition of iron, suggesting that the mechanism of phage action on Ca involves denial of iron. Birefringence studies on added phage showed an ordered structure of binding to Ca. Electron microscopic observations indicated phage aggregation in the biofilm extracellular matrix. Bacteriophage–fungal interactions may be a general feature with several pathogens in the fungal kingdom.

ACS Style

Hasan Nazik; Lydia-Marie Joubert; Patrick R. Secor; Johanna Sweere; Paul L. Bollyky; Gabriele Sass; Lynette Cegelski; David A. Stevens. Pseudomonas phage inhibition of Candida albicans. Microbiology 2017, 163, 1568 -1577.

AMA Style

Hasan Nazik, Lydia-Marie Joubert, Patrick R. Secor, Johanna Sweere, Paul L. Bollyky, Gabriele Sass, Lynette Cegelski, David A. Stevens. Pseudomonas phage inhibition of Candida albicans. Microbiology. 2017; 163 (11):1568-1577.

Chicago/Turabian Style

Hasan Nazik; Lydia-Marie Joubert; Patrick R. Secor; Johanna Sweere; Paul L. Bollyky; Gabriele Sass; Lynette Cegelski; David A. Stevens. 2017. "Pseudomonas phage inhibition of Candida albicans." Microbiology 163, no. 11: 1568-1577.

Journal article
Published: 04 October 2017 in Open Forum Infectious Diseases
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ACS Style

Gabriele Sass; Hasan Nazik; John Penner; Hemi Shah; Karl V Clemons; Marie-Christine Groleau; Eric Déziel; David A Stevens. Studies of Pseudomonas aeruginosa Mutants Indicate Pyoverdine as the Central Factor in Inhibition of Aspergillus fumigatus Biofilm. Open Forum Infectious Diseases 2017, 4, 1 .

AMA Style

Gabriele Sass, Hasan Nazik, John Penner, Hemi Shah, Karl V Clemons, Marie-Christine Groleau, Eric Déziel, David A Stevens. Studies of Pseudomonas aeruginosa Mutants Indicate Pyoverdine as the Central Factor in Inhibition of Aspergillus fumigatus Biofilm. Open Forum Infectious Diseases. 2017; 4 (suppl_1):1.

Chicago/Turabian Style

Gabriele Sass; Hasan Nazik; John Penner; Hemi Shah; Karl V Clemons; Marie-Christine Groleau; Eric Déziel; David A Stevens. 2017. "Studies of Pseudomonas aeruginosa Mutants Indicate Pyoverdine as the Central Factor in Inhibition of Aspergillus fumigatus Biofilm." Open Forum Infectious Diseases 4, no. suppl_1: 1.

Research article
Published: 16 June 2017 in PLOS ONE
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In persons with structural lung disease, particularly those with cystic fibrosis (CF), chronic airway infections cause progressive loss of lung function. CF airways can be colonized by a variety of microorganisms; the most frequently encountered bacterial and fungal pathogens are Pseudomonas aeruginosa and Aspergillus fumigatus, respectively. Co-infection with P. aeruginosa and A. fumigatus often results in a more rapid loss of lung function, indicating that interactions between these pathogens affect infection pathogenesis. There has been renewed interest in the use of viruses (bacteriophage, mycoviruses) as alternatives to antibiotics to treat these infections. In previous work, we found that filamentous Pf bacteriophage produced by P. aeruginosa directly inhibited the metabolic activity of A. fumigatus by binding to and sequestering iron. In the current study, we further examined how filamentous Pf bacteriophage affected interactions between P. aeruginosa and A. fumigatus. Here, we report that the antifungal properties of supernatants collected from P. aeruginosa cultures infected with Pf bacteriophage were substantially less inhibitory towards A. fumigatus biofilms. In particular, we found that acute infection of P. aeruginosa by Pf bacteriophage inhibited the production of the virulence factor pyoverdine. Our results raise the possibility that the reduced production of antimicrobials by P. aeruginosa infected by Pf bacteriophage may promote conditions in CF airways that allow co-infection with A. fumigatus to occur, exacerbating disease severity. Our results also highlight the importance of considering how the use of bacteriophage as therapeutic agents could affect the behavior and composition of polymicrobial communities colonizing sites of chronic infection.

ACS Style

Patrick R. Secor; Gabriele Sass; Hasan Nazik; David A. Stevens. Effect of acute predation with bacteriophage on intermicrobial aggression by Pseudomonas aeruginosa. PLOS ONE 2017, 12, e0179659 -e0179659.

AMA Style

Patrick R. Secor, Gabriele Sass, Hasan Nazik, David A. Stevens. Effect of acute predation with bacteriophage on intermicrobial aggression by Pseudomonas aeruginosa. PLOS ONE. 2017; 12 (6):e0179659-e0179659.

Chicago/Turabian Style

Patrick R. Secor; Gabriele Sass; Hasan Nazik; David A. Stevens. 2017. "Effect of acute predation with bacteriophage on intermicrobial aggression by Pseudomonas aeruginosa." PLOS ONE 12, no. 6: e0179659-e0179659.