Faculty Opinions recommendation of Isolation of Phage Lysins That Effectively Kill Pseudomonas aeruginosa in Mouse Models of Lung and Skin Infection.

The study was performed to isolate and characterize some selected bacteria from skin lesion of sheep, goat and cattle of different rearing condition. Intensive and semi-intensive housing systems were considered for this study. A total of (n=60) skin wound swab and pus samples were collected for this study during the study period. Among them (n=30) samples were collected from intensive farms and (n=30) samples were collected from semi-intensive farms. Staphylococcus aureus infections were found 70% skin lesion for sheep, 30% for goat and 60% for cattle and Pseudomonas aeruginosa infections were found 5% skin lesion for sheep, 15% for goat and 15% for cattle. Semi-intensive farm animals were more infected by bacteria than intensive farm animals. Staphylococcus aureus affected 53.33% in intensive farm animal and 66.67% in semi-intensive farm animal. Pseudomonas aeruginosa affected 10% animal in intensive housing system and 13.33% in semi-intensive housing system. The organisms were isolated and characterized by morphological, cultural and biochemical characteristics and identified by polymerase chain reaction. Staphylococcus aureus produced yellowish colony in nutrient agar and golden yellow colony in mannitol salt agar. Positive isolates were produced β–hemolysis in blood agar. Pseudomonas aeruginosa produced characteristic colony in nutrient agar but not produce pigment. Pseudomonas aeruginosa produced colorless colony in MaCconkey agar, violet colony in EMB agar and produced hemolysis in blood agar. Staphylococcus aureus showed Gram positive, cocci shaped and grapes like arrangement and Pseudomonas aeruginosa showed Gram negative, short rod shaped. Staphylococcus aureus fermented five basic sugars and produced gas and Pseudomonas aeruginosa fermented dextrose and mannitol. Both organisms were catalase positive, only Pseudomonas aeruginosa was oxidase positive. Pseudomonas aeruginosa isolates were further characterized by PCR amplification of toxA gene primer. Staphylococcus aureus skin infection treatment was noticed more effective by erythromycin and gentamicin and Pseudomonas aeruginosa skin infection treatment more effective by ciprofloxacin and gentamicin. Both the organisms were found to be amoxicillin resistant. This is the first and preliminary report of molecular characterization of Pseudomonas aeruginosa from skin lesion of sheep, goat and cattle associated with a different rearing condition of the animals in Bangladesh. Asian J. Med. Biol. Res. June 2019, 5(2): 117-125

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Lung arginase expression and activity is increased in cystic fibrosis mouse models

Journal of Applied Physiology ◽

10.1152/japplphysiol.00167.2014 ◽

2014 ◽

Vol 117 (3) ◽

pp. 284-288 ◽

Cited By ~ 9

Author(s):

Thomas Jaecklin ◽

Julia Duerr ◽

Hailu Huang ◽

Mahroukh Rafii ◽

Christine E. Bear ◽

...

Keyword(s):

Cystic Fibrosis ◽

Pseudomonas Aeruginosa ◽

Mouse Models ◽

Arginase Activity ◽

Mouse Lung ◽

Wild Type ◽

Arginase 1 ◽

Isolated Lung ◽

Deficient Mice ◽

Expression And Activity

The activity of arginase is increased in airway secretions of patients with cystic fibrosis (CF). Downstream products of arginase activity may contribute to CF lung disease. We hypothesized that pulmonary arginase expression and activity would be increased in mouse models of CF and disproportionally increased in CF mice with Pseudomonas aeruginosa pneumonia. Expression of arginase isoforms in lung tissue was quantified with reverse transcriptase-PCR in naive cystic fibrosis transmembrane conductance regulator ( Cftr)-deficient mice and β-epithelial sodium channel-overexpressing [β-ENaC-transgenic (Tg)] mice. An isolated lung stable isotope perfusion model was used to measure arginase activity in Cftr-deficient mice before and after intratracheal instillation of Pseudomonas aeruginosa. The expression of arginase-2 in lung was increased in adult Cftr-deficient animals and in newborn β-ENaC-Tg. Arginase-1 lung expression was normal in Cftr-deficient and in newborn β-ENaC-Tg mice, but was increased in β-ENaC-Tg mice at age 1, 3, and 6 wk. Arginase activity was significantly higher in lung (5.0 ± 0.7 vs. 3.2 ± 0.3 nmol·−1·h−1, P = 0.016) and airways (204.6 ± 49.8 vs. 79.3 ± 17.2 nmol·−1·h−1, P = 0.045) of naive Cftr-deficient mice compared with sex-matched wild-type littermate controls. Infection with Pseudomonas aeruginosa resulted in a far greater increase in lung arginase activity in Cftr-deficient mice (10-fold) than in wild-type controls (6-fold) ( P = 0.01). This is the first ex vivo characterization of arginase expression and activity in CF mouse lung and airways. Our data show that pulmonary arginase expression and activity is increased in CF mice, especially with Pseudomonas aeruginosa infections.

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Monomodular Pseudomonas aeruginosa phage JG004 lysozyme (Pae87) contains a bacterial surface-active antimicrobial peptide-like region and a possible substrate-binding subdomain

10.1101/2022.01.10.475687 ◽

2022 ◽

Author(s):

Roberto Vázquez ◽

Mateo Seoane-Blanco ◽

Virginia Rivero-Buceta ◽

Susana Ruiz ◽

Mark J. van Raaij ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Antimicrobial Activity ◽

Cell Wall ◽

Antimicrobial Peptide ◽

Outer Membrane ◽

Catalytic Domain ◽

Biochemical Study ◽

Substrate Binding ◽

Binding Region ◽

Phage Lysins

Phage lysins are a source of novel antimicrobials to tackle the bacterial antibiotic resistance crisis. The engineering of phage lysins is being explored as a game-changing technological strategy for introducing a more precise approach in the way we apply antimicrobial therapy. Such engineering efforts will benefit from a better understanding of lysin structure and function. In this work, the antimicrobial activity of the endolysin from Pseudomonas aeruginosa phage JG004, termed Pae87, has been characterized. This lysin had been previously identified as an antimicrobial agent candidate, able to interact with the Gram-negative surface and disrupt it. Further evidence is hereby provided on this matter, based on a structural and biochemical study. A high-resolution crystal structure of Pae87 complexed with a peptidoglycan fragment showed a separate substrate-binding region within the catalytic domain, 18 Å away from the catalytic site and located at the opposite side of the lysin molecule. This substrate binding region was conserved among phylogenetically related lysins lacking an additional cell wall binding domain, but not among those containing such a module. Two glutamic acids were identified as relevant for the peptidoglycan degradation activity, although Pae87 antimicrobial activity was seemingly unrelated to it. In contrast, an antimicrobial peptide-like region within Pae87 C-terminus, named P87, was found to be able to actively disturb the outer membrane and have antibacterial activity by itself. Therefore, we propose an antimicrobial mechanism for Pae87 in which the P87 peptide plays the role of binding to the outer membrane and disrupting the cell wall function, either with or without the participation of Pae87 catalytic activity.

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Novel Lytic Phages Protect Cells and Mice against Pseudomonas aeruginosa Infection

Journal of Virology ◽

10.1128/jvi.01832-20 ◽

2021 ◽

Author(s):

Feng Chen ◽

Xingjun Cheng ◽

Jianbo Li ◽

Xiefang Yuan ◽

Xiuhua Huang ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Mouse Models ◽

Bacterial Infections ◽

Phage Therapy ◽

Inflammatory Responses ◽

Multi Drug Resistance ◽

Bacterial Strains ◽

Genetic Traits

With the fast emergence of serious antibiotic resistance and the lagged discovery of novel antibacterial drugs, phage therapy for pathogenic bacterial infections has acquired great attention in the clinics. However, development of therapeutic phages also faces tough challenges, such as laborious screening and time to generate effective phage drugs since each phage may only lyse a narrow scope of bacterial strains. Identifying highly effective phages with broad host ranges is crucial for improving phage therapy. Here, we isolated and characterized several lytic phages from various environments specific for Pseudomonas aeruginosa by testing their growth, invasion, host ranges, and potential for killing targeted bacteria. Importantly, we identified several therapeutic phages (HX1, PPY9, and TH15) with broad host ranges to lyse laboratory strains and clinical isolates of P. aeruginosa with multi-drug resistance (MDR) both in vitro and in mouse models. In addition, we analyzed critical genetic traits related to the high-level broad host coverages by genome sequencing and subsequent computational analysis against known phages. Collectively, our findings establish that these novel phages may have potential for further development as therapeutic options for patients who fail to respond to conventional treatments. IMPORTANCE Novel lytic phages isolated from various environmental settings were systematically characterized for their critical genetic traits, morphology structures, host ranges against laboratory strains and clinical multi-drug resistant (MDR) Pseudomonas aeruginosa, and antibacterial capacity both in vitro and in mouse models. First, we characterized the genetic traits and compared with other existing phages. Furthermore, we utilized acute pneumonia induced by laboratorial strain PAO1, and W19, an MDR clinical isolate and chronic pneumonia by agar beads laden with FDR1, a mucoid phenotype strain isolated from the sputum of a cystic fibrosis (CF) patient. Consequently, we found that these phages not only suppress bacteria in vitro but also significantly reduce the infection symptom and disease progression in vivo, including lowered bug burdens, inflammatory responses and lung injury in mice, suggesting that they may be further developed as therapeutic agents against MDR P. aeruginosa.

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Pseudomonas aeruginosa infection reveals a Caspase-1-dependent neutrophil pyroptosis pathway that restrains damaging Histone release

10.1101/2021.06.28.450116 ◽

2021 ◽

Author(s):

Remi Planes ◽

Karin Santoni ◽

Salimata Bagayoko ◽

David Pericat ◽

Pierre-Jean Bordignon ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Mouse Models ◽

Regulatory Function ◽

Cytokine Release ◽

Caspase 1 ◽

Pseudomonas Aeruginosa Infection

Neutrophils mediate essential immune and microbicidal processes. Consequently, to counteract neutrophil attack, pathogens have developed various virulence strategies. Here, we showed that Pseudomonas aeruginosa (P. aeruginosa) phospholipase ExoU drives pathological NETosis in neutrophils. Surprisingly, inhibition of ExoU activity uncovered a fully functional Caspase-1-driven pyroptosis pathway in neutrophils. Mechanistically, activated NLRC4 inflammasome promoted Caspase-1-dependent Gasdermin-D activation, IL-1β cytokine release and neutrophil pyroptosis. Whereas both pyroptotic and netotic neutrophils released alarmins, only NETosis liberated the destructive DAMPs Histones, which exacerbated Pseudomonas-induced mouse lethality. To the contrary, subcortical actin allowed pyroptotic neutrophils to physically limit poisonous inflammation by keeping Histones intracellularly. Finally, mouse models of infection highlighted that both NETosis and neutrophil Caspase-1 contributed to P. aeruginosa spreading. Overall, we established the host deleterious consequences of Pseudomonas-induced-NETosis but also uncovered an unsuspected ability of neutrophils to undergo Caspase-1-dependent pyroptosis, a process where neutrophils exhibit a self-regulatory function that limit Histone release.

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LL37 peptide@silver nanoparticles: combining the best of the two worlds for skin infection control

Nanoscale ◽

10.1039/c4nr01284d ◽

2014 ◽

Vol 6 (11) ◽

pp. 5725-5728 ◽

Cited By ~ 34

Author(s):

Mariana Vignoni ◽

Hasitha de Alwis Weerasekera ◽

Madeline J. Simpson ◽

Jaywant Phopase ◽

Thien-Fah Mah ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Silver Nanoparticles ◽

Infection Control ◽

Human Skin ◽

Biofilm Formation ◽

Skin Fibroblast ◽

Skin Infection ◽

Antibacterial Properties ◽

Human Skin Fibroblast ◽

Fibroblast Proliferation

LL37-capped silver nanoparticles have antibacterial properties including inhibition of Pseudomonas aeruginosa biofilm formation, but do not affect human skin fibroblast proliferation.

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Isolation of Phage Lysins That Effectively KillPseudomonas aeruginosain Mouse Models of Lung and Skin Infection

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00024-19 ◽

2019 ◽

Vol 63 (7) ◽

Cited By ~ 13

Author(s):

Assaf Raz ◽

Anna Serrano ◽

Anaise Hernandez ◽

Chad W. Euler ◽

Vincent A. Fischetti

Keyword(s):

Outer Membrane ◽

Bacterial Infections ◽

Skin Infection ◽

Therapeutic Potential ◽

Treatment Options ◽

Opportunistic Pathogen ◽

Infection Model ◽

Gram Negative ◽

Content Type ◽

Phage Lysins

ABSTRACTMultidrug resistance (MDR) is rapidly increasing in prevalence among isolates of the opportunistic pathogenPseudomonas aeruginosa, leaving few treatment options. Phage lysins are cell wall hydrolases that have a demonstrated therapeutic potential against Gram-positive pathogens; however, the outer membrane of Gram-negative bacteria prevents most lysins from reaching the peptidoglycan, making them less effective as therapeutics. Nevertheless, a few lysins from Gram-negative bacterial phage can penetrate the bacterial outer membrane with the aid of an amphipathic tail found in the molecule’s termini. In this work, we took a phylogenetic approach to systematically identify those lysins fromP. aeruginosaphage that would be most effective therapeutically. We isolated and performed preliminary characterization of 16 lysins and chose 2 lysins, PlyPa03 and PlyPa91, which exhibited >5-log killing activity againstP. aeruginosaand other Gram-negative pathogens (particularlyKlebsiellaandEnterobacter). These lysins showed rapid killing kinetics and were active in the presence of high concentrations of salt and urea and under pH conditions ranging from 5.0 to 10.0. Activity was not inhibited in the presence of the pulmonary surfactant beractant (Survanta). While neither enzyme was active in 100% human serum, PlyPa91 retained activity in low serum concentrations. The lysins were effective in the treatment of aP. aeruginosaskin infection in a mouse model, and PlyPa91 protected mice in a lung infection model, making these lysins potential drug candidates for Gram-negative bacterial infections of the skin or respiratory mucosa.

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58 Route of application plays a distinct role for the outcome of a Pseudomonas aeruginosa airway infection in cystic fibrosis mouse models

Journal of Cystic Fibrosis ◽

10.1016/s1569-1993(11)60077-5 ◽

2011 ◽

Vol 10 ◽

pp. S15 ◽

Cited By ~ 1

Author(s):

A. Munder ◽

F. Wölbeling ◽

U. Baumann ◽

E. Gulbins ◽

B. Tümmler

Keyword(s):

Cystic Fibrosis ◽

Pseudomonas Aeruginosa ◽

Mouse Models ◽

Airway Infection ◽

Cystic Fibrosis Mouse ◽

Distinct Role

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Acute-phase response and the effect of phytopreparation Feverfew (Tanacetum parthenium) in dogs with experimental Pseudomonas aeruginosa skin infection

10.15547/bjvm.873 ◽

2016 ◽

Vol 19 (1) ◽

pp. 72-77

Author(s):

M. Andonova ◽

V. Urumova ◽

D. Dimitrova ◽

E. Slavov ◽

P. Dzhelebov ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Acute Phase ◽

Acute Phase Response ◽

Skin Infection ◽

Phase Response ◽

Tanacetum Parthenium

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Small proline-rich proteins (SPRRs) are epidermally produced antimicrobial proteins that defend the cutaneous barrier by direct bacterial membrane disruption

10.1101/2021.09.01.458578 ◽

2021 ◽

Author(s):

Chenlu Zhang ◽

Zehan Hu ◽

Abdul G Lone ◽

Methinee Artami ◽

Marshall Edwards ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Bactericidal Activity ◽

Skin Infection ◽

Mouse Skin ◽

Systemic Infection ◽

Bacterial Membrane ◽

Antimicrobial Proteins ◽

Antimicrobial Function ◽

Skin Commensals ◽

Insight Into

Human skin functions as a physical barrier, preventing the entry of foreign pathogens while also accommodating a myriad of commensal microorganisms. A key contributor to the skin landscape is the sebaceous gland. Mice devoid of sebocytes are prone to skin infection, yet our understanding of how sebocytes function in host defense is incomplete. Here we show that the small proline-rich proteins, SPRR1 and SPRR2 are bactericidal in skin. SPRR1B and SPPR2A were induced in human sebocytes by exposure to the bacterial cell wall component lipopolysaccharide (LPS). Further, LPS injected into mouse skin triggered the expression of the mouse SPRR orthologous genes, Sprr1a and Sprr2a, through stimulation of MYD88. Both mouse and human SPRR proteins displayed potent bactericidal activity against MRSA (methicillin-resistant Staphylococcus aureus), Pseudomonas aeruginosa and skin commensals. Thus, Sprr1a-/-;Sprr2a-/- mice are more susceptible to MRSA and Pseudomonas aeruginosa skin infection. Lastly, mechanistic studies demonstrate that SPRR proteins exert their bactericidal activity through binding and disruption of the bacterial membrane. Taken together, these findings provide insight into the regulation and antimicrobial function of SPRR proteins in skin and how the skin defends the host against systemic infection.

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