Inhibition of Zoonotic Pathogens Naturally Found in Pig Manure by Black Soldier Fly Larvae and Their Intestine Bacteria

Black soldier fly (BSF) larvae are often exposed to organic waste which harbors abundant zoonotic pathogens. We investigated the ability of BSF larvae to inhibit the zoonotic pathogens naturally found in pig manure. The zoonotic pathogens populations were detected by using selective medium during the conversion. Results showed that the viability of the zoonotic pathogens in pig manure was significantly affected. After eight days of conversion, the Coliform populations were undetected, and Staphylococcus aureus and Salmonella spp. decreased significantly on the eighth day. Antimicrobial assays of the purified recombinant defensin-like peptide 4 (DLP4) showed that this peptide exhibits inhibitory activity against S. aureus, Salmonella enterica serovar typhimurium, and Escherichia coli in vitro. Bacteria BSF-CL and BSF-F were isolated from the larvae gut, and both inhibited the growth of S. aureus and E. coli, but Salmonella spp. was sensitive to the BSF-CL strain (but not to the BSF-F strain). The results from our experiments indicate that BSF larvae are capable of functionally inhibiting potential zoonotic pathogens in pig manure through a variety of mechanisms including antimicrobial peptides expression and the gut associate microorganisms. This study provides a theoretical basis for further study on the combined mechanism of BSF larvae immunity and its gut microbes against the zoonotic pathogens in pig manure.

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Effect of Inactivation of degS on Salmonella enterica Serovar Typhimurium In Vitro and In Vivo

Infection and Immunity ◽

10.1128/iai.73.1.459-463.2005 ◽

2005 ◽

Vol 73 (1) ◽

pp. 459-463 ◽

Cited By ~ 23

Author(s):

Gary Rowley ◽

Andrew Stevenson ◽

Jan Kormanec ◽

Mark Roberts

Keyword(s):

Sigma Factor ◽

Salmonella Enterica ◽

Salmonella Enterica Serovar Typhimurium ◽

Wild Type ◽

Alternative Pathways ◽

E Coli ◽

Mammalian Tissues ◽

Serovar Typhimurium

ABSTRACT The alternative sigma factor (RpoE σE) enables Salmonella enterica serovar Typhimurium to adapt to stressful conditions, such as oxidative stress, nutrient deprivation, and growth in mammalian tissues. Infection of mice by Salmonella serovar Typhimurium also requires σE. In Escherichia coli, activation of the σE pathway is dependent on proteolysis of the anti-sigma factor RseA and is initiated by DegS. DegS is also important in order for E. coli to cause extraintestinal infection in mice. We constructed a degS mutant of the serovar Typhimurium strain SL1344 and compared its behavior in vitro and in vivo with those of its wild-type (WT) parent and an isogenic rpoE mutant. Unlike E. coli degS strains, the Salmonella serovar Typhimurium degS strain grew as well as the WT strain at 42°C. The degS mutant survived very poorly in murine macrophages in vitro and was highly attenuated compared with the WT strain for both the oral and parenteral routes of infection in mice. However, the degS mutant was not as attenuated as the serovar Typhimurium rpoE mutant: 100- to 1,000-fold more degS bacteria than rpoE bacteria were present in the livers and spleens of mice 24 h after intraperitoneal challenge. In most assays, the rpoE mutant was more severely affected than the degS mutant and a σE-dependent reporter gene was more active in the degS mutant than the rpoE strain. These findings indicate that degS is important for activation of the σE pathway in serovar Typhimurium but that alternative pathways for σE activation probably exist.

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Differential Contribution of Toll-Like Receptors 4 and 2 to the Cytokine Response to Salmonella enterica Serovar Typhimurium and Staphylococcus aureus in Mice

Infection and Immunity ◽

10.1128/iai.71.10.6058-6062.2003 ◽

2003 ◽

Vol 71 (10) ◽

pp. 6058-6062 ◽

Cited By ~ 51

Author(s):

Annalisa Lembo ◽

Christoph Kalis ◽

Carsten J. Kirschning ◽

Vincenzo Mitolo ◽

Emilio Jirillo ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Salmonella Enterica Serovar Typhimurium ◽

Gram Negative Bacteria ◽

Toll Like Receptors ◽

Cytokine Induction ◽

Serovar Typhimurium ◽

And Staphylococcus Aureus ◽

Differential Contribution

ABSTRACT The contribution of murine Toll-like receptors 2 and 4 (TLR2 and -4, respectively) to cytokine induction by heat-killed bacteria was analyzed in vitro and in vivo. Gram-negative bacteria induced cytokines primarily via TLR4; the contribution of TLR2 was only minor. Neither TLR4 nor, surprisingly, TLR2 was required in the MyD88-dependent response to Staphylococcus aureus.

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ANTIMICROBIAL ACTIVITY AND CHEMICAL CHARACTERIZATION OF LAUREL ESSENTIAL OIL

Arquivos de Ciências Veterinárias e Zoologia da UNIPAR ◽

10.25110/arqvet.v24i2cont.2021.8512 ◽

2021 ◽

Vol 24 (2cont) ◽

Author(s):

Juliana Olívia Nicolao ◽

Franciana Aparecida Volpato Bellaver ◽

Volmir Kist ◽

Daniel Radin ◽

Marcelo Mendes De Haro ◽

...

Keyword(s):

Antimicrobial Activity ◽

Essential Oil ◽

Pathogenic Bacteria ◽

Salmonella Enterica Serovar Typhimurium ◽

Chemical Characterization ◽

Serovar Typhimurium ◽

Total Composition ◽

And Staphylococcus Aureus

The factors that arouse interest in the study of essential oils as biocidal agents are numerous, such as the fact that they have antibacterial, antifungal, insecticidal, antioxidant, anti-inflammatory and larvicidal properties. The objective of this work was to evaluate the antimicrobial activity, in vitro, of the laurel (Laurus nobilis L) essential oil on the growth of pathogenic bacteria Salmonella enterica serovar Typhimurium ATCC 14028 and Staphylococcus aureus ATCC 25923, at different exposure times, as well as to perform the chemical characterization. Twenty compounds were identified and quantified, representing 96.57% of the total composition. The class of oxygenated monoterpenes represented the majority class of the essential oil, with 1,8-cineol (33.8%) as the substance found in greater quantity, followed by linalool (17.79%). The third constituent in greater quantity was sabinene (12.23%), belonging to the group of monoterpene hydrocarbons. Terpinyl acetate (9.41%) was also considered to be quantitatively representative. Laurel essential oil showed bacteriostatic activity against S. Typhimurium ATCC 14028 and S. aureus ATCC 25923.

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Fungal xenosiderophores from mycobiota and diet promote Salmonella colonization of the inflamed gut

10.21203/rs.3.rs-1175303/v1 ◽

2022 ◽

Author(s):

William Santus ◽

Amisha Rana ◽

Jason Devlin ◽

Kaitlyn Kiernan ◽

Carol Jacob ◽

...

Keyword(s):

Salmonella Enterica Serovar Typhimurium ◽

Competitive Growth ◽

Infectious Colitis ◽

Functional Relationships ◽

Siderophore Receptors ◽

Serovar Typhimurium ◽

Intestinal Pathogen ◽

Bacteria And Fungi

Abstract The fungal gut microbiota (mycobiota) has been implicated in diseases that disturb gut homeostasis. However, little is known about functional relationships between bacteria and fungi in the gut during infectious colitis. We investigated the role of fungal metabolites during infection with the intestinal pathogen Salmonella enterica serovar Typhimurium. We found that in the gut lumen, both the mycobiota and fungi present in the diet can be a source of siderophores, small molecules that scavenge iron from the host. The ability to use fungal siderophores, such as ferrichrome and coprogen, conferred a competitive growth advantage to Salmonella strains expressing the fungal siderophore receptors FhuA or FhuE in vitro and in a mouse model. Our study highlights the role of inter-kingdom cross-feeding between fungi and Salmonella, and elucidates a new function for the gut mycobiota, revealing the importance of these under-studied members of the gut ecosystem during bacterial infection.

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Detection of Escherichia coli O157, Salmonella enterica Serovar Typhimurium, and Staphylococcal Enterotoxin B in a Single Sample Using Enzymatic Bio-Nanotransduction

Journal of Food Protection ◽

10.4315/0362-028x-70.4.841 ◽

2007 ◽

Vol 70 (4) ◽

pp. 841-850 ◽

Cited By ~ 8

Author(s):

JOSH R. BRANEN ◽

MARTHA J. HASS ◽

ERIN R. DOUTHIT ◽

WUSI C. MAKI ◽

A. LARRY BRANEN

Keyword(s):

Escherichia Coli ◽

Salmonella Enterica ◽

Salmonella Enterica Serovar Typhimurium ◽

Staphylococcal Enterotoxin B ◽

Escherichia Coli O157 ◽

Dna Templates ◽

E Coli ◽

Serovar Typhimurium ◽

Biological Recognition ◽

Enterotoxin B

Enzymatic bio-nanotransduction is a biological detection scheme based on the production of nucleic acid nano-signals (RNA) in response to specific biological recognition events. In this study, we applied an enzymatic bio-nanotransduction system to the detection of important food-related pathogens and a toxin. Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and staphylococcal enterotoxin B (SEB) were chosen because of the implications of these targets to food safety. Primary antibodies to each of the targets were used to functionalize magnetic beads and produce biological recognition elements (antibodies) conjugated to nano-signal–producing DNA templates. Immunomagnetic capture that was followed by in vitro transcription of DNA templates bound to target molecules produced RNA nano-signals specific for every target in the sample. Discrimination of RNA nano-signals with a standard enzyme-linked oligonucleotide fluorescence assay provided a correlation between nano-signal profiles and target concentrations. The estimated limit of detection was 2.4 × 103 CFU/ml for E. coli O157:H7, 1.9 × 104 CFU/ml for S. enterica serovar Typhimurium, and 0.11 ng/ml for SEB with multianalyte detection in buffer. Low levels of one target were also detected in the presence of interference from high levels of the other targets. Finally, targets were detected in milk, and detection was improved for E. coli O157 by heat treatment of the milk.

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Attenuation of Salmonella enterica Serovar Typhimurium by Altering Biological Functions of Murein Lipoprotein and Lipopolysaccharide

Infection and Immunity ◽

10.1128/iai.73.12.8433-8436.2005 ◽

2005 ◽

Vol 73 (12) ◽

pp. 8433-8436 ◽

Cited By ~ 8

Author(s):

A. A. Fadl ◽

J. Sha ◽

G. R. Klimpel ◽

J. P. Olano ◽

C. L. Galindo ◽

...

Keyword(s):

Salmonella Enterica ◽

Salmonella Enterica Serovar Typhimurium ◽

Biological Functions ◽

Double Knockout ◽

In Vivo Models ◽

Background Strain ◽

Knockout Mutants ◽

Serovar Typhimurium

ABSTRACT We constructed Salmonella enterica serovar Typhimurium double-knockout mutants in which either the lipoprotein A (lppA) or the lipoprotein B (lppB) gene was deleted from an msbB-negative background strain by marker exchange mutagenesis. These mutants were highly attenuated when tested with in vitro and in vivo models of Salmonella pathogenesis.

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Persistent Salmonella enterica Serovar Typhimurium Infection Induces Protease Expression During Intestinal Fibrosis

Inflammatory Bowel Diseases ◽

10.1093/ibd/izz070 ◽

2019 ◽

Vol 25 (10) ◽

pp. 1629-1643 ◽

Cited By ~ 3

Author(s):

Katrin Ehrhardt ◽

Natalie Steck ◽

Reinhild Kappelhoff ◽

Stephanie Stein ◽

Florian Rieder ◽

...

Keyword(s):

Protease Inhibitors ◽

Salmonella Enterica ◽

Salmonella Enterica Serovar Typhimurium ◽

Salmonella Infection ◽

Intestinal Fibrosis ◽

Fibrotic Tissue ◽

Serovar Typhimurium ◽

Inflammatory Bowel ◽

Protease Expression

AbstractBackgroundIntestinal fibrosis is a common and serious complication of Crohn’s disease characterized by the accumulation of fibroblasts, deposition of extracellular matrix, and formation of scar tissue. Although many factors including cytokines and proteases contribute to the development of intestinal fibrosis, the initiating mechanisms and the complex interplay between these factors remain unclear.MethodsChronic infection of mice with Salmonella enterica serovar Typhimurium was used to induce intestinal fibrosis. A murine protease-specific CLIP-CHIP microarray analysis was employed to assess regulation of proteases and protease inhibitors. To confirm up- or downregulation during fibrosis, we performed quantitative real-time polymerase chain reaction (PCR) and immunohistochemical stainings in mouse tissue and tissue from patients with inflammatory bowel disease. In vitro infections were used to demonstrate a direct effect of bacterial infection in the regulation of proteases.ResultsMice develop severe and persistent intestinal fibrosis upon chronic infection with Salmonella enterica serovar Typhimurium, mimicking the pathology of human disease. Microarray analyses revealed 56 up- and 40 downregulated proteases and protease inhibitors in fibrotic cecal tissue. Various matrix metalloproteases, serine proteases, cysteine proteases, and protease inhibitors were regulated in the fibrotic tissue, 22 of which were confirmed by quantitative real-time PCR. Proteases demonstrated site-specific staining patterns in intestinal fibrotic tissue from mice and in tissue from human inflammatory bowel disease patients. Finally, we show in vitro that Salmonella infection directly induces protease expression in macrophages and epithelial cells but not in fibroblasts.ConclusionsIn summary, we show that chronic Salmonella infection regulates proteases and protease inhibitors during tissue fibrosis in vivo and in vitro, and therefore this model is well suited to investigating the role of proteases in intestinal fibrosis.

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Salmonella enterica Serovar Typhimurium and Escherichia coli Survival in Estuarine Bank Sediments

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15112597 ◽

2018 ◽

Vol 15 (11) ◽

pp. 2597 ◽

Cited By ~ 2

Author(s):

Mahbubul Siddiqee ◽

Rebekah Henry ◽

Rebecca Coulthard ◽

Christelle Schang ◽

Richard Williamson ◽

...

Keyword(s):

Escherichia Coli ◽

Salmonella Enterica ◽

Salmonella Enterica Serovar Typhimurium ◽

Growth Patterns ◽

Estuarine Sediments ◽

Human Pathogens ◽

Indicator Organisms ◽

Fecal Indicator ◽

E Coli ◽

Serovar Typhimurium

Estuarine bank sediments have the potential to support the survival and growth of fecal indicator organisms, including Escherichia coli. However, survival of fecal pathogens in estuarine sediments is not well researched and therefore remains a significant knowledge gap regarding public health risks in estuaries. In this study, simultaneous survival of Escherichia coli and a fecal pathogen, Salmonella enterica serovar Typhimurium, was studied for 21 days in estuarine bank sediment microcosms. Observed growth patterns for both organisms were comparable under four simulated scenarios; for continuous-desiccation, extended-desiccation, periodic-inundation, and continuous-inundation systems, logarithmic decay coefficients were 1.54/day, 1.51/day, 0.14/day, and 0.20/day, respectively, for E. coli, and 1.72/day, 1.64/day, 0.21/day, and 0.24/day for S. Typhimurium. Re-wetting of continuous-desiccated systems resulted in potential re-growth, suggesting survival under moisture-limited conditions. Key findings from this study include: (i) Bank sediments can potentially support human pathogens (S. Typhimurium), (ii) inundation levels influence the survival of fecal bacteria in estuarine bank sediments, and (iii) comparable survival rates of S. Typhimurium and E. coli implies the latter could be a reliable fecal indicator in urban estuaries. The results from this study will help select suitable monitoring and management strategies for safer recreational activities in urban estuaries.

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Antibacterial activity and in vitro cytotoxicity evaluation of alginate-AgNP fibers

Textile Research Journal ◽

10.1177/0040517516652350 ◽

2016 ◽

Vol 87 (11) ◽

pp. 1377-1386 ◽

Cited By ~ 3

Author(s):

Xihui Zhao ◽

Qun Li ◽

Xiaowen Li ◽

Yanzhi Xia ◽

Bing Wang ◽

...

Keyword(s):

Antibacterial Activity ◽

Treatment Time ◽

Biological Activities ◽

In Vitro Cytotoxicity ◽

Cell Counting ◽

Logarithmic Phase ◽

E Coli ◽

Alginate Fibers ◽

And Staphylococcus Aureus

Biopolymer nanocomposites containing metal nanoparticles have attracted much attention due to their excellent properties and broad applications. In this work, alginate fibers embedded with silver nanoparticles (AgNPs) were prepared. The as-obtained alginate-AgNP fibers exhibited antibacterial activity against both Gram microorganisms of model microbes Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive). A growth kinetic study with S. aureus and E. coli displayed the inhibition of bacterial growth at the logarithmic phase. The cytotoxic effect of the fibers in human cervical cancer (HeLa) cells was assessed by cell counting kit-8 (CCK-8) assay and flow cytometry. The as-prepared alginate-AgNP fibers, particularly with high amount and long treatment time, showed high cell-killing efficiency. These findings emphasize that such alginate-AgNP fibers with multifaceted biological activities are a promising material for applications in the textile or biomedical fields.

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