scholarly journals Isolation of bacteriophages with lytic activity against a newly identified Pantoea agglomerans

2019 ◽  
Vol 77 (1) ◽  
pp. 50-55
Author(s):  
N. Korniienko ◽  
E. Dukhno ◽  
A. Kharina ◽  
I. Budzanivska
Keyword(s):  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Pantoea Agglomerans ◽  
Waste Waters ◽  
Electronic Microscopy ◽  
Isolation And Identification ◽  
Phage Isolate ◽  
Biochemical Identification ◽  
Identification Of Bacteria

In a consequence of agricultural human activity, a set of phytopathogenic bacteria gain new properties and ability to cause diseases in animal and human organisms. Moreover, bacterial loss of sensitivity to antibiotics becomes more increasing threat. The most effective alternative method of processing of plants are bacteriophages. The aim of this work is isolation and identification of a vegetable enterobacteria and search of its specific bacteriophages. Methods: biochemical identification of bacteria, analysis on sensitivity to antibiotics by means of disks, titration and accumulation of virus, electronic microscopy. Results: from onions samples with symptoms of a bacteriosis several bacteria were isolated. One of them was identified as Pantoea agglomerans. The sensitivity of this isolate to antibiotics was investigated, the resistance to cefalexin and norfloxacin is revealed. The bacteriophage specific to this bacteria is isolated from waste waters. The morphology of a bacteriophage is investigated by means of electronic microscopy, the virus belongs to the Myoviridae family. Phytopathogenic properties of bacteria and the antibacterial activity of phage isolate were investigated on potatoes in vitro. P. agglomerans led to development of a bacteriosis on potatoes cubes, and the isolated bacteriophage successfully inhibited its growth. Conclusions: This study demonstrated that common vegetables such as onions could be a source of human pathogenic bacteria. In this work, we isolated P.agglomerans, member of family Enterobacteriaceae. Taking into account that this bacteria was unsensitive to some antibiotics, it can be regarded as an alarming sign. The use of bacteriophages could solve problems of antimicriobial resistance and protecting of crops from bacterial infections. Isolated bacteriophage from waste waters inhibited growth of P.agglomerans in vitro showing that it could be considered as a part of phage drugs.

scholarly journals TSPphg Lysin from the Extremophilic Thermus Bacteriophage TSP4 as a Potential Antimicrobial Agent against Both Gram-Negative and Gram-Positive Pathogenic Bacteria

Viruses ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 192 ◽  
Author(s):  
Feng Wang ◽  
Xinyu Ji ◽  
Qiupeng Li ◽  
Guanling Zhang ◽  
Jiani Peng ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Infection Model ◽  
Bacterial Cells ◽  
Skin Damage ◽  
Gram Positive ◽  
Antibiotic Resistant ◽  
Gram Negative

New strategies against antibiotic-resistant bacterial pathogens are urgently needed but are not within reach. Here, we present in vitro and in vivo antimicrobial activity of TSPphg, a novel phage lysin identified from extremophilic Thermus phage TSP4 by sequencing its whole genome. By breaking down the bacterial cells, TSPphg is able to cause bacteria destruction and has shown bactericidal activity against both Gram-negative and Gram-positive pathogenic bacteria, especially antibiotic-resistant strains of Klebsiella pneumoniae, in which the complete elimination and highest reduction in bacterial counts by greater than 6 logs were observed upon 50 μg/mL TSPphg treatment at 37 °C for 1 h. A murine skin infection model further confirmed the in vivo efficacy of TSPphg in removing a highly dangerous and multidrug-resistant Staphylococcus aureus from skin damage and in accelerating wound closure. Together, our findings may offer a therapeutic alternative to help fight bacterial infections in the current age of mounting antibiotic resistance, and to shed light on bacteriophage-based strategies to develop novel anti-infectives.

scholarly journals UVC Light Prophylaxis for Cutaneous Wound Infections in Mice

2012 ◽  
Vol 56 (7) ◽  
pp. 3841-3848 ◽  
Author(s):  
Tianhong Dai ◽  
Barbara Garcia ◽  
Clinton K. Murray ◽  
Mark S. Vrahas ◽  
Michael R. Hamblin
Keyword(s):  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Light Exposure ◽  
Dna Lesions ◽  
Bacterial Cells ◽  
Wound Infections ◽  
Content Type ◽  
Cutaneous Wound ◽  
Thickness Skin

ABSTRACTUVC light has long been known to be highly germicidal but has not been much developed as a therapy for infections. This study investigated the potential of UVC light for the prophylaxis of infections developing in highly contaminated superficial cutaneous wounds.In vitrostudies demonstrated that the pathogenic bacteriaPseudomonas aeruginosaandStaphylococcus aureuswere inactivated at UVC light exposures much lower than those needed for a similar effect on mammalian keratinocytes. Mouse models of partial-thickness skin abrasions infected with bioluminescentP. aeruginosaandS. aureuswere developed. Approximately 107bacterial cells were inoculated onto wounds measuring 1.2 by1.2 cm on the dorsal surfaces of mice. UVC light was delivered at 30 min after bacterial inoculation. It was found that for both bacterial infections, UVC light at a single radiant exposure of 2.59 J/cm2reduced the bacterial burden in the infected mouse wounds by approximately 10-fold in comparison to those in untreated mouse wounds (P< 0.00001). Furthermore, UVC light increased the survival rate of mice infected withP. aeruginosaby 58.3% (P= 0.0023) and increased the wound healing rate in mice infected withS. aureusby 31.2% (P< 0.00001). DNA lesions were observed in the UVC light-treated mouse wounds; however, the lesions were extensively repaired by 48 h after UVC light exposure. These results suggested that UVC light may be used for the prophylaxis of cutaneous wound infections.

scholarly journals In-vitro pathogen inhibition: Comparing the inhibitory effects of a complex multistrain synbiotic with simple probiotics containing the yeast Saccharomyces boulardii or Lactobacillus rhamnosus bacteria

2019 ◽  
Author(s):  
Jacek Piatek ◽  
Henning Sommermeyer ◽  
Arleta Ciechelska-Rybarczyk ◽  
Malgorzata Bernatek
Keyword(s):  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Lactobacillus Rhamnosus ◽  
Saccharomyces Boulardii ◽  
Human Pathogens ◽  
Inhibitory Effects ◽  
Probiotic Strains ◽  
Pathogen Inhibition ◽  
Different Strains

AbstractSupplementation with probiotics is considered as alternative treatment or adjuvant therapy for a number of bacterial infections for which the use of antibiotics is either not recommended or emerging antibiotic resistance is a major concern. Inhibition of the growth of pathogenic bacteria has been related to a number of different activities of probiotic bacteria or yeasts, some of which are very specific for particular strains of probiotics. As the different inhibition activities might act additively or even synergistically, probiotic multistrain products are discussed as potentially being more effective in pathogen inhibition than products containing one or a small number of probiotic strains. The present study investigated the in vitro inhibition of Escherichia (E.) coli, Shigella spp., Salmonella (S.) typhimurium and Clostridum (Cl.) difficile, all being human pathogens of significant worldwide healthcare concerns. The probiotic containing the yeast Sacharomyces (S.) boulardii inhibited all four pathogens. Similar inhibitions were observed with a bacterial probiotic containing three different strains (Pen, E/N and Oxy) of Lactobacillus (Lc.) rhamnosus. Compared to the inhibition found for these probiotics, the inhibitory effects of a complex multistrain synbiotic, containing nine different probiotic strains (6 Lactobacilli and 3 Bifidobacteria) and the prebiotic fructooligosaccharide (FOS), were significantly stronger. The stronger inhibition by the complex multistrain synbiotic was observed for all four tested pathogens. Our findings support a hypothesis that complex synbiotic products containing a larger number of different strains combined with a prebiotic component might be more attractive candidates for further clinical characterization than simpler probiotics containing one or only few probiotic strains.

In-vitro evaluation of cisplatin nanoparticles encompass natural polymer

2020 ◽  
Vol 3 (1) ◽  
pp. 1-6
Author(s):  
Bhavani J ◽  
Sunil Kumar Prajapati ◽  
Ravichandran S
Keyword(s):  
Antibacterial Activity ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Research Work ◽  
Dilution Method ◽  
Bacterial Strains ◽  
Active Components ◽  
Synthetic Drugs

Opportunistic bacterial infections are common in the various parts of human body. In recent years bacterial species have shown resistance against a number of synthetic drugs. This study measured the antibacterial activity of bacterial strains against five common pathogenic bacteria related strains. Cup plate method and two fold serial dilution method were used to evaluated by antibacterial activity by the help of different bacterial related strains. The results revealed that Cisplatin (CIP) using natural as a polymer showed a minimum inhibitory concentration (MIC) at 250 mg/ml to 500 mg/ml of the broth against all bacterial strains. CIP using natural as a polymer was prepared different doses1000 μg/ml and 2000 μg/ ml and measured zone of inhibition dose dementedly reduced when compared to standard. The CIP using natural as a polymer exhibited strong anti-bacterial activity against five different species of bacteria and this may be attributed to various active components. Our research work has been indicated Nanoparticles containing CIP using natural as a polymer formulated for the enhanced anti-cancer activity through antimicrobial mechanism. 

Antimicrobial Activity of Myrtus communis L., Cinnamomum verum and Eugenia caryophyllata Alcoholic Mixtures

2020 ◽  
Vol 16 (2) ◽  
pp. 207-212
Author(s):  
Wissam Zam ◽  
Ali Ali ◽  
Walaa Ibrahim
Keyword(s):  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Antimicrobial Activities ◽  
Diffusion Method ◽  
Myrtus Communis ◽  
Myrtus Communis L ◽  
Inhibition Zones ◽  
Alcoholic Mixtures

Background and Objective: With the significant increase in the prevalence of infectious diseases and the development of drug resistance by human pathogenic bacteria, there is a continuous need to discover new antimicrobial compounds from plants. Methods: Four extracts of wild Myrtus communis L. berries (myrtle berries) were prepared with the addition of Cinnamomum verum and Eugenia caryophyllata. The extracts were screened in vitro for their antimicrobial activities using agar-well diffusion method against Escherichia coli, Staphylococcus aureus, Enterobacter cloacae, Listeria monocytogenes, Pseudomonas aeruginosa and Proteus mirabilis cultures. Results: The inhibition zones ranged from 12 to 22 mm. The MICs values of extracts lies between the ranges of 30 to 100 mg/ml. Of the extracts studied, the most active ones were those obtained from the myrtle berries:cloves, myrtle berries:cinnamon:cloves with the highest inhibition zones 22 mm and 17mm against S. aureus and L. monocytogenes at 50 mg/ml and 80 mg/ml, respectively. None of the extracts was active against E. coli and P. mirabilis. Conclusion: The present investigations have exposed that the myrtle berries:cloves, myrtle berries: cinnamon:cloves extracts could be used in traditional medicine as natural antimicrobial agents in treatment the bacterial infections.

scholarly journals Identification of Quorum-Sensing Inhibitors Disrupting Signaling between Rgg and Short Hydrophobic Peptides in Streptococci

mBio ◽  
2015 ◽  
Vol 6 (3) ◽  
Author(s):  
Chaitanya Aggarwal ◽  
Juan Cristobal Jimenez ◽  
Hyun Lee ◽  
George E. Chlipala ◽  
Kiira Ratia ◽  
...  
Keyword(s):  
Quorum Sensing ◽  
Communication Networks ◽  
Drug Targets ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Chemical Compounds ◽  
Content Type ◽  
Hydrophobic Peptides ◽  
Biofilm Development

ABSTRACTBacteria coordinate a variety of social behaviors, important for both environmental and pathogenic bacteria, through a process of intercellular chemical signaling known as quorum sensing (QS). As microbial resistance to antibiotics grows more common, a critical need has emerged to develop novel anti-infective therapies, such as an ability to attenuate bacterial pathogens by means of QS interference. Rgg quorum-sensing pathways, widespread in the phylumFirmicutes, employ cytoplasmic pheromone receptors (Rgg transcription factors) that directly bind and elicit gene expression responses to imported peptide signals. In the human-restricted pathogenStreptococcus pyogenes, the Rgg2/Rgg3 regulatory circuit controls biofilm development in response to the short hydrophobic peptides SHP2 and SHP3. Using Rgg-SHP as a model receptor-ligand target, we sought to identify chemical compounds that could specifically inhibit Rgg quorum-sensing circuits. Individual compounds from a diverse library of known drugs and drug-like molecules were screened for their ability to disrupt complexes of Rgg and FITC (fluorescein isothiocyanate)-conjugated SHP using a fluorescence polarization (FP) assay. The best hits were found to bind Rgg3in vitrowith submicromolar affinities, to specifically abolish transcription of Rgg2/3-controlled genes, and to prevent biofilm development inS. pyogeneswithout affecting bacterial growth. Furthermore, the top hit, cyclosporine A, as well as its nonimmunosuppressive analog, valspodar, inhibited Rgg-SHP pathways in multiple species ofStreptococcus. The Rgg-FITC-peptide-based screen provides a platform to identify inhibitors specific for each Rgg type. Discovery of Rgg inhibitors constitutes a step toward the goal of manipulating bacterial behavior for purposes of improving health.IMPORTANCEThe global emergence of antibiotic-resistant bacterial infections necessitates discovery not only of new antimicrobials but also of novel drug targets. Since antibiotics restrict microbial growth, strong selective pressures to develop resistance emerge quickly in bacteria. A new strategy to fight microbial infections has been proposed, namely, development of therapies that decrease pathogenicity of invading organisms while not directly inhibiting their growth, thus decreasing selective pressure to establish resistance. One possible means to this goal is to interfere with chemical communication networks used by bacteria to coordinate group behaviors, which can include the synchronized expression of genes that lead to disease. In this study, we identified chemical compounds that disrupt communication pathways regulated by Rgg proteins in species ofStreptococcus. Treatment of cultures ofS. pyogeneswith the inhibitors diminished the development of biofilms, demonstrating an ability to control bacterial behavior with chemicals that do not inhibit growth.

scholarly journals In Vitro Selective Antibacterial and Antiproliferative Effects of Ethanolic Extracts from Cambodian and Philippine Plants Used in Folk Medicine for Diarrhea Treatment

2021 ◽  
Vol 12 ◽  
Author(s):  
Tomas Kudera ◽  
Barbora Fiserova ◽  
Marie Korytakova ◽  
Ivo Doskocil ◽  
Hana Salmonova ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Pathogenic Bacteria ◽  
Folk Medicine ◽  
Intestinal Bacteria ◽  
Intestinal Cancer ◽  
Inhibitory Effects ◽  
Isolation And Identification ◽  
Broth Microdilution Method ◽  
Ethanolic Extracts

Bacterial diarrhea remains a global health problem, especially in developing tropical countries. Moreover, dysbiosis caused by diarrheagenic bacteria and inappropriate antimicrobial treatment has been associated with intestinal carcinogenesis. Despite the rich tradition of the use of herbs for the treatment of gastrointestinal disorders in Cambodian and Philippine folk medicine, many of them have not yet been systematically studied for their in vitro selective inhibitory effects on intestinal bacteria and cells. In the present study, in vitro inhibitory activities of 35 ethanolic extracts derived from 32 Cambodian and Philippine medicinal plants were determined by broth microdilution method against 12 pathogenic bacteria. Furthermore, cytotoxicity against intestinal cancer cells (Caco-2 and HT-29) using thiazolyl blue tetrazolium bromide cytotoxicity assay and safety to six beneficial intestinal bacteria (bifidobacteria and lactobacilli) and intestinal normal cells (FHs 74 Int) were determined for the antimicrobially active extracts. Selectivity indices (SIs) were calculated among the averages of minimum inhibitory concentrations (MICs), half-maximal inhibitory concentrations (IC50), and 80% inhibitory concentrations of proliferation (IC80) for each type of the tested agents. The extracts of Artocarpus blancoi (Elmer) Merr. (Moraceae), Ancistrocladus tectorius (Lour.) Merr. (Ancistrocladaceae), and Pentacme siamensis (Miq.) Kurz (Dipterocarpaceae) produced significant growth-inhibitory effects (MICs = 32–512 μg/ml) against intestinal pathogenic bacteria at the concentrations nontoxic to normal intestinal cells (IC80 values &gt;512 μg/ml; SIs = 0.11–0.2). Moreover, the extract of P. siamensis (Miq.) Kurz was relatively safe to beneficial bacteria (MICs ≥512 μg/ml; SI = 0.1), and together with A. blancoi (Elmer) Merr., they selectively inhibited intestinal cancer cells (IC50 values ≥51.98 ± 19.79 μg/ml; SIs = 0.3 and 0.6). Finally, a strong selective antiproliferative effect on cancer cells (IC50 values 37.89 ± 2.68 to 130.89 ± 13.99 μg/ml; SIs = 0.5) was exerted by Ehretia microphylla Lam. (Boraginaceae), Lagerstroemia cochinchinensis Pierre ex Gagnep. (Lythraceae), and Melastoma saigonense (Kuntze) Merr. (Melastomataceae) (leaves with flower buds). The results suggest that the above-mentioned species are promising materials for the development of new selective antibacterial and antiproliferative agents for the treatment of infectious diarrhea and associated intestinal cancer diseases. However, further research is needed regarding the isolation and identification of their active constituents.

scholarly journals Meningoencephalitis in farmed monosex Nile tilapia (Oreochromis niloticus L.) caused by Streptococcus agalactiae

2017 ◽  
Vol 25 (3) ◽  
pp. 187-200 ◽  
Author(s):  
Harresh Adikesavalu ◽  
Sayani Banerjee ◽  
Avijit Patra ◽  
Thangapalam Jawahar Abraham
Keyword(s):  
Streptococcus Agalactiae ◽  
Oreochromis Niloticus ◽  
Nile Tilapia ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Sequencing Analysis ◽  
Isolation And Identification ◽  
Aeromonas Sobria ◽  
Rdna Sequencing ◽  
New Research

Abstract Aquaculture of tilapia is a new research venture in India. With intensification in farming practices, tilapia are increasingly susceptible to bacterial infections. This article describes the isolation and identification of pathogenic bacteria from cultured monosex Nile tilapia, Oreochromis niloticus (L.), that experienced moderate to severe mortalities in West Bengal, India between September and August 2014 and histopathological alterations in various organs. Gram-positive diplococci, identified as Streptococcus agalactiae with Streptococcus identification kits and 16S rDNA sequencing analysis, were isolated from the brain, operculum, and kidney. Other bacteria from the kidney were identified as Aeromonas sobria, A. caviae, Klebsiella pneumoniae ssp. pneumoniae, Escherichia coli, and Enterobacter cloacae. Staphylococcus epidermis was isolated from opercular hemorrhages. Histological sections of the infected tilapia brain revealed meningoencephalitis and granulomatous lesions. Sections from other organs indicated congestion, hemorrhagic and hyperplastic cells, necrosis, vacuolation, hemosiderin deposition, hypertrophic nuclei, melanomacrophage aggregation, and ruptured veins. This report is the first description of S. agalactiae as a primary pathogen causing meningoencephalitis in cultured tilapia in India.

scholarly journals Unique Mode of Cell Division by the Mycobacterial Genetic Resister Clones Emerging De Novo from the Antibiotic-Surviving Population

mSphere ◽  
2020 ◽  
Vol 5 (6) ◽  
Author(s):  
Kishor Jakkala ◽  
Avraneel Paul ◽  
Atul Pradhan ◽  
Rashmi Ravindran Nair ◽  
Deepti Sharan ◽  
...  
Keyword(s):  
Cell Division ◽  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
De Novo ◽  
Bacterial Strains ◽  
Antibiotic Resistant ◽  
Content Type ◽  
Cellular Processes ◽  
Unique Mode

ABSTRACT The emergence of antibiotic genetic resisters of pathogenic bacteria poses a major public health challenge. The mechanism by which bacterial antibiotic genetic resister clones formed de novo multiply and establish a resister population remained unknown. Here, we delineated the unique mode of cell division of the antibiotic genetic resisters of Mycobacterium smegmatis and Mycobacterium tuberculosis formed de novo from the population surviving in the presence of bactericidal concentrations of rifampicin or moxifloxacin. The cells in the rifampicin/moxifloxacin-surviving population generated elevated levels of hydroxyl radical-inflicting mutations. The genetic mutants selected against rifampicin/moxifloxacin became multinucleated and multiseptated and developed multiple constrictions. These cells stochastically divided multiple times, producing sister-daughter cells phenomenally higher in number than what could be expected from their generation time. This caused an abrupt, unexpectedly high increase in the rifampicin/moxifloxacin resister colonies. This unique cell division behavior was not shown by the rifampicin resisters formed naturally in the actively growing cultures. We could detect such abrupt increases in the antibiotic resisters in others’ and our earlier data on the antibiotic-exposed laboratory/clinical M. tuberculosis strains, M. smegmatis and other bacteria in in vitro cultures, infected macrophages/animals, and tuberculosis patients. However, it went unnoticed/unreported in all those studies. This phenomenon occurring in diverse bacteria surviving against different antibiotics revealed the broad significance of the present study. We speculate that the antibiotic-resistant bacillary clones, which emerge in patients with diverse bacterial infections, might be using the same mechanism to establish an antibiotic resister population quickly in the continued presence of antibiotics. IMPORTANCE The bacterial pathogens that are tolerant to antibiotics and survive in the continued presence of antibiotics have the chance to acquire genetically resistant mutations against the antibiotics and emerge de novo as antibiotic resisters. Once the antibiotic resister clone has emerged, often with compromise on growth characteristics, for the protection of the species, it is important to establish an antibiotic-resistant population quickly in the continued presence of the antibiotic. In this regard, the present study has unraveled multinucleation and multiseptation followed by multiple constrictions as the cellular processes used by the bacteria for quick multiplication to establish antibiotic-resistant populations. The study also points out the same phenomenon occurring in other bacterial systems investigated in our laboratory and others’ laboratories. Identification of these specific cellular events involved in quick multiplication offers additional cellular processes that can be targeted in combination with the existing antibiotics’ targets to preempt the emergence of antibiotic-resistant bacterial strains.

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