scholarly journals Biological and Genomic Characterization of a Novel Jumbo Bacteriophage, vB_VhaM_pir03 with Broad Host Lytic Activity against Vibrio harveyi

Pathogens ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1051
Author(s):  
Gerald N. Misol ◽  
Constantina Kokkari ◽  
Pantelis Katharios
Keyword(s):  
Phage Therapy ◽  
Vibrio Harveyi ◽  
Burst Size ◽  
Disease Outbreaks ◽  
Artemia Salina ◽  
Open Reading Frames ◽  
Lytic Activity ◽  
Economic Losses ◽  
Phylogenomic Analysis ◽  
Antibiotic Resistant

Vibrio harveyi is a Gram-negative marine bacterium that causes major disease outbreaks and economic losses in aquaculture. Phage therapy has been considered as a potential alternative to antibiotics however, candidate bacteriophages require comprehensive characterization for a safe and practical phage therapy. In this work, a lytic novel jumbo bacteriophage, vB_VhaM_pir03 belonging to the Myoviridae family was isolated and characterized against V. harveyi type strain DSM19623. It had broad host lytic activity against 31 antibiotic-resistant strains of V. harveyi, V. alginolyticus, V. campbellii and V. owensii. Adsorption time of vB_VhaM_pir03 was determined at 6 min while the latent-phase was at 40 min and burst-size at 75 pfu/mL. vB_VhaM_pir03 was able to lyse several host strains at multiplicity-of-infections (MOI) 0.1 to 10. The genome of vB_VhaM_pir03 consists of 286,284 base pairs with 334 predicted open reading frames (ORFs). No virulence, antibiotic resistance, integrase encoding genes and transducing potential were detected. Phylogenetic and phylogenomic analysis showed that vB_VhaM_pir03 is a novel bacteriophage displaying the highest similarity to another jumbo phage, vB_BONAISHI infecting Vibrio coralliilyticus. Experimental phage therapy trial using brine shrimp, Artemia salina infected with V. harveyi demonstrated that vB_VhaM_pir03 was able to significantly reduce mortality 24 h post infection when administered at MOI 0.1 which suggests that it can be an excellent candidate for phage therapy.

scholarly journals ISOLATION, CHARACTERIZATION AND GENOME ANALYSIS OF A NOVEL VIRULENT ESCHERICHIA COLI BACTERIOPHAGE VB_ECOM_011D4

2021 ◽  
Vol 6 ◽  
pp. 27-35
Keyword(s):  
High Throughput ◽  
High Throughput Sequencing ◽  
Phage Therapy ◽  
Burst Size ◽  
Large Subunit ◽  
Alternative Therapy ◽  
Gc Content ◽  
Open Reading Frames ◽  
Promising Alternative ◽  
E Coli

Phage therapy is a promising alternative therapy for the treatment of E. coli infection. Although the total number of phages on the earth is as high as 10 31 , the reported phages and thoroughly studied are very limited. Therefore, the continuous discovery of new phages and in-depth research will provide materials for the wide application of phage therapy in the future. In this study, a novel E. coli phage vB_EcoM_011D4 was isolated from sewage samples, and the biological characteristics were studied. Electron microscopy and homology analysis results showed that vB_EcoM_011D4 belongs to the family Myoviridae. One-step growth curve showing the latent period of vB_EcoM_011D4 was 10 min, with the burst size of 115 PFU/cell. Additionally, Phage vB_EcoM_011D4 was highly stabled under different temperatures (range 4 – 70 ℃) and pH conditions (range 6 – 10). At the same time, its genome was subjected to high-throughput sequencing and compared with the reported phages. The results of high-throughput sequencing assembly showed that vB_EcoM_011D4 is a linear, double-stranded DNA virus containing 163764 bp, with an average GC content of 40.50%, and a total of 273 open reading frames (ORFs). Genomic comparison analysis revealed that most of the ORFs were similar to Enterobacteria phage Phi1 and RB49. However, ORF147 and ORF148 putative DNA methylase family protein is less than 67% homology with already published phages. In addition, the phylogenetic analysis of terminates large subunit showed that it belongs to a new branch and shows less than 50 similarities to reported phages. There is no lysogenic, toxin or antibiotic-resistant related gene was found in the genome of vB_EcoM_011D4. In summary, vB_EcoM_011D4 is a newly discovered phage, which can be further studied for elucidating the phage diversity and it is benefits for the wide application of phage therapy.

scholarly journals Isolation and Characterization of a Novel Myophage Abp9 Against Pandrug Resistant Acinetobacater baumannii

2020 ◽  
Vol 11 ◽  
Author(s):  
Lingli Jiang ◽  
Jingjie Tan ◽  
Yi Hao ◽  
Qi Wang ◽  
Xiaorui Yan ◽  
...  
Keyword(s):  
Phage Therapy ◽  
Open Reading Frames ◽  
Lytic Phage ◽  
Therapeutic Effects ◽  
Antibiotic Resistant ◽  
Isolation And Characterization ◽  
Double Stranded Dna ◽  
Wide Range ◽  
Hospital Sewage

Acinetobacter baumannii (A. baumannii) has emerged as one of the most troublesome pathogens in health care institutions. A. baumannii can cause a wide range of diseases in humans, including pneumonia and septicemia. Phage therapy has drawn great interest from medical researchers as a potential way to control infections by antibiotic-resistant A. baumannii. Using a pandrug-resistant clinical A. baumannii isolate ABZY9 as an indicator, we isolated a lytic phage Abp9 from hospital sewage. Abp9 belongs to myoviridae family and shows a wider host range of 12%. Abp9 contains a linear double-stranded DNA genome of 44,820 bp with a G + C content of 37.69%. The Abp9 genome contains 80 open reading frames, but lacks any known virulence genes or lysogen-formation genes. In a systemic A. baumannii infection mouse models, Abp9 treatment showed good therapeutic effects. We have also observed an excellent lytic activity against A. baumannii in biofilm form of growth in vitro. All of these suggest that Abp9 is a good candidate for the phage therapy against drug-resistant A. baumannii infections.

scholarly journals Complete Genome Sequence of a Jumbo Bacteriophage, vB_pir03, against Vibrio harveyi

2020 ◽  
Vol 9 (44) ◽  
Author(s):  
Gerald N. Misol ◽  
Constantinta Kokkari ◽  
Pantelis Katharios
Keyword(s):  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Vibrio Harveyi ◽  
Disease Outbreaks ◽  
Open Reading Frames ◽  
Content Type ◽  
Reading Frames

ABSTRACT Vibrio harveyi is a persistent pathogen responsible for disease outbreaks in aquaculture. We have sequenced the genome of a jumbo Vibrio phage, vB_pir03, isolated in Greece. Here, we present the complete genome of vB_pir03, which consists of 286,284 bp and 336 open reading frames.

scholarly journals Isolation and characterization of Pseudomonas aeruginosa bacteriophages — potential agents for phage therapy

2021 ◽  
Author(s):  
MA Kornienko ◽  
NS Kuptsov ◽  
DI Danilov ◽  
RB Gorodnichev ◽  
MV Malakhova ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Phage Therapy ◽  
Illumina Miseq ◽  
Multidrug Resistant ◽  
Open Reading Frames ◽  
Lytic Activity ◽  
Isolation And Characterization ◽  
Double Stranded Dna ◽  
Activity Spectrum

Pseudomonas aeruginosa — is one of the pathogens characterized by the critical number of multidrug-resistant (MDR) strains. Phage therapy is considered an alternative to antibiotics, especially in treatment of infections caused by MDR strains. The aim of this study was to isolate and characterize P. aeruginosa phages that could potentially be suitable for treating infectious diseases. To isolate the P. aeruginosa phages, enrichment cultures were used. The lytic activity spectrum was confirmed by spot testing on 40 P. aeruginosa strains. Whole-genome sequencing was performed using Illumina MiSeq instrument. Phylogenetic analysis was done using VICTOR tool. Isolated phages vB_PaeA-55-1w and vB_PaeM-198 from Autographiviridae and Myoviridae families, respectively, had a broad spectrum of lytic activity (about 50% each), including lysis of MDR strains. The genomes vB_PaeA-55-1w and vB_PaeM-198 comprise double-stranded DNA of 42.5 and 66.3 kbp in length, respectively. Open reading frames were annotated for both phages (52 for vB_PaeA-55-1w, and 95 for vB_PaeM-198), no integrases and toxins were detected. On a phylogenetic tree, vB_PaeA-55-1w phage was clustered with phages from the Phikmvvirus genus (Autographiviridae family), which are also used in phage therapy. vB_PaeM-198 phage was clustered with phages from the Pbunavirus genus (Myoviridae family). vB_PaeA-55-1w and vB_PaeM-198 phages could be considered as candidates for phage therapy and may be used to treat infections caused by MDR P. aeruginosa.

Vibrio harveyi virulence gene expression in vitro and in vivo during infection in black tiger shrimp Penaeus monodon

2020 ◽  
Vol 139 ◽  
pp. 153-160
Author(s):  
S Peeralil ◽  
TC Joseph ◽  
V Murugadas ◽  
PG Akhilnath ◽  
VN Sreejith ◽  
...  
Keyword(s):  
Gene Expression ◽  
Virulence Genes ◽  
Vibrio Harveyi ◽  
Penaeus Monodon ◽  
Challenge Test ◽  
Virulence Gene ◽  
Economic Losses ◽  
Virulence Gene Expression

Luminescent Vibrio harveyi is common in sea and estuarine waters. It produces several virulence factors and negatively affects larval penaeid shrimp in hatcheries, resulting in severe economic losses to shrimp aquaculture. Although V. harveyi is an important pathogen of shrimp, its pathogenicity mechanisms have yet to be completely elucidated. In the present study, isolates of V. harveyi were isolated and characterized from diseased Penaeus monodon postlarvae from hatcheries in Kerala, India, from September to December 2016. All 23 tested isolates were positive for lipase, phospholipase, caseinase, gelatinase and chitinase activity, and 3 of the isolates (MFB32, MFB71 and MFB68) showed potential for significant biofilm formation. Based on the presence of virulence genes, the isolates of V. harveyi were grouped into 6 genotypes, predominated by vhpA+ flaB+ ser+ vhh1- luxR+ vopD- vcrD+ vscN-. One isolate from each genotype was randomly selected for in vivo virulence experiments, and the LD50 ranged from 1.7 ± 0.5 × 103 to 4.1 ± 0.1 × 105 CFU ml-1. The expression of genes during the infection in postlarvae was high in 2 of the isolates (MFB12 and MFB32), consistent with the result of the challenge test. However, in MFB19, even though all genes tested were present, their expression level was very low and likely contributed to its lack of virulence. Because of the significant variation in gene expression, the presence of virulence genes alone cannot be used as a marker for pathogenicity of V. harveyi.

scholarly journals Bacteriophages to Control Multi-Drug Resistant Enterococcus faecalis Infection of Dental Root Canals

2021 ◽  
Vol 9 (3) ◽  
pp. 517
Author(s):  
Mohamed El-Telbany ◽  
Gamal El-Didamony ◽  
Ahmed Askora ◽  
Eman Ariny ◽  
Dalia Abdallah ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Root Canal ◽  
Phage Therapy ◽  
Ex Vivo ◽  
Burst Size ◽  
Resistant Bacteria ◽  
Drug Resistant ◽  
Range Analysis ◽  
Root Canals

Phage therapy is an alternative treatment to antibiotics that can overcome multi-drug resistant bacteria. In this study, we aimed to isolate and characterize lytic bacteriophages targeted against Enterococcus faecalis isolated from root canal infections obtained from clinics at the Faculty of Dentistry, Ismalia, Egypt. Bacteriophage, vB_ZEFP, was isolated from concentrated wastewater collected from hospital sewage. Morphological and genomic analysis revealed that the phage belongs to the Podoviridae family with a linear double-stranded DNA genome, consisting of 18,454, with a G + C content of 32.8%. Host range analysis revealed the phage could infect 10 of 13 E. faecalis isolates exhibiting a range of antibiotic resistances recovered from infected root canals with efficiency of plating values above 0.5. One-step growth curves of this phage showed that it has a burst size of 110 PFU per infected cell, with a latent period of 10 min. The lytic activity of this phage against E. faecalis biofilms showed that the phage was able to control the growth of E. faecalis in vitro. Phage vB_ZEFP could also prevent ex-vivo E. faecalis root canal infection. These results suggest that phage vB_ZEFP has potential for application in phage therapy and specifically in the prevention of infection after root canal treatment.

scholarly journals Bacteriophages: the possible solution to treat infections caused by pathogenic bacteria

2017 ◽  
Vol 63 (11) ◽  
pp. 865-879 ◽  
Author(s):  
Ayman El-Shibiny ◽  
Salma El-Sahhar
Keyword(s):  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Phage Therapy ◽  
Multidrug Resistant ◽  
Clinical Applications ◽  
Western World ◽  
Resistant Bacteria ◽  
Vaccine Production ◽  
Bacterial Populations ◽  
Antibiotic Resistant

Since their discovery in 1915, bacteriophages have been used to treat bacterial infections in animals and humans because of their unique ability to infect their specific bacterial hosts without affecting other bacterial populations. The research carried out in this field throughout the 20th century, largely in Georgia, part of USSR and Poland, led to the establishment of phage therapy protocols. However, the discovery of penicillin and sulfonamide antibiotics in the Western World during the 1930s was a setback in the advancement of phage therapy. The misuse of antibiotics has reduced their efficacy in controlling pathogens and has led to an increase in the number of antibiotic-resistant bacteria. As an alternative to antibiotics, bacteriophages have become a topic of interest with the emergence of multidrug-resistant bacteria, which are a threat to public health. Recent studies have indicated that bacteriophages can be used indirectly to detect pathogenic bacteria or directly as biocontrol agents. Moreover, they can be used to develop new molecules for clinical applications, vaccine production, drug design, and in the nanomedicine field via phage display.

Prevalence and Multidrug-Resistance Salmonella in Swine Production Chain in a Central Province, Thailand

2021 ◽  
Author(s):  
Kaknokrat Chonsin ◽  
Ruchirada Changkwanyeun ◽  
Achiraya Siriphap ◽  
Apiradee Intarapuk ◽  
Watsawan Prapasawat ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Disease Outbreaks ◽  
Cross Sectional Study ◽  
Single Type ◽  
Economic Losses ◽  
Cross Sectional ◽  
Production Chain ◽  
Extended Spectrum Beta Lactamase ◽  
Present Cross Sectional Study ◽  
Cutting Boards

Salmonella causes foodborne disease outbreaks worldwide and raises considerable concerns about public health and economic losses. To determine prevalence, serovar, antimicrobial resistance (AMR) patterns, and extended-spectrum beta-lactamase (ESBL) genes, the present cross-sectional study collected a total of 418 fecal, carcass (three slaughterhouses), pork and cutting board (four markets) samples from a province in central Thailand in 2017 and 2018. Results showed that 65.1% (272/418) of samples were positive for Salmonella. The percentage of Salmonella positive samples from markets (88.8%; 158/178) was significantly higher than those from slaughterhouses (47.5%; 114/240) ( P<0.05 ). In total, 1,030 isolates were identified; of these, 409 were assigned to 45 serovars with S. Rissen (20%; 82/409) being the most common. New serovars of Thai isolates, S. Cannstatt and S. Braubach, were identified in market and slaughterhouse samples, respectively. AMR of Salmonella isolates showed that 73.9% (133/180) of 19 different serovars exhibited multidrug resistance (MDR). Screening for ESBL production showed that 10.3% (41/399) of isolates were ESBL positive. ESBL-producing Salmonella isolates in market samples (75.6%; 31/41) were significantly higher than those in slaughterhouse samples (24.4%; 10/41) ( P<0.05 ). In market samples, 77.4% (24/31) were isolated from pork and 22.6% (7/31) from cutting boards. Nine ESBL-producing isolates carried single type ESBL genes bla TEM (9.8%; 4/41) or bla CTX-M (12.2%; 5/41), while 11 (26.8%) carried both bla TEM and bla CTX-M . No ESBL-producing Salmonella isolate carried the gene bla SHV . Results suggest that pigs, their flesh, and cutting boards could be reservoirs for widespread MDR, ESBL-producing Salmonella outbreak across the food chain.

The Isolation of specifically lytic phages along with their extracted endolysins as antibacterial agents to MDR Enterococcus faecalis

2021 ◽  
pp. 4547-4554
Author(s):  
Shaymaa Husham Ahmed ◽  
Rand R. Hafidh
Keyword(s):  
Enterococcus Faecalis ◽  
Bacterial Growth ◽  
Phage Therapy ◽  
Burst Size ◽  
Alternative Therapy ◽  
Multidrug Resistant ◽  
Multiple Drug ◽  
Specific Phage ◽  
Multiple Drug Resistant ◽  
Phage Cocktail

Background: Multidrug-resistant (MDR) enterococci have become a major problem in recent times and have been reported increasingly around the world. Lytic phages infect bacteria leading to rapid host death with limited risk of phage transduction, underlining the increasing interest in potential phage therapy in the future. Objective (s): The aim of this study is to use phage therapy as alternative approach for treatment of Enterococcus faecalis infections that recorded as MDR in Iraq to tackle this problem. Materials and Methods: Thirty E. faecalis isolates were collected from patients with different infectious diseases such as urinary tract infection (UTI), diabetic foot, septicemia, and wound infections. The isolation of specific lytic phages was from different environmental sources such as (sewage, and wastewater). The biokinetic assays were carried out to measure the characteristics of the isolated phage. The study of the bacteriophage and the formed phage cocktail infectivity against isolates E.faecalis was tested by the top layer assay. The phage endolysin was extracted from the best bacteriophage that gave best results. Results: All the isolated E.faecalis was reported as MDR in this study. About 75 E.faecalis specific phages were isolated and purified. All the isolated bacteria were 100% sensitive to the lytic phages. The formed phage cocktail was capable to create inhibition zones on the most bacterial isolates' lawns. The molecular weight and the concentration of the extracted endolysin was evaluated in this study and found to be as (48 kDa) and (0.5mg/ml), respectively. The antibacterial activity of the extracted endolysin was evaluated by the turbidity reduction assay. A clear decline in the bacterial growth was manifested (5x107 CFU/ml) to (1x104 CFU/ml), in which the bacterial growth was reduced by (3.63 log). The endolysin found to be effective against 90% of E.faeclais isolates. Conclusion: The activity of the isolated specific phage together with the activity of the formed phage cocktail, were efficient as successful and inexpensive method of therapy against MDR E.faecalis. The potential of the extracted endolysin over the phage therapy was verified in this study. The coverage rate and the absence of resistant E.faecalis to the phage and its endolysin had emphasized on the importance of this alternative therapy to commonly used antibiotics. List of abbreviation: MDR = multiple drug-resistant, E. faecalis = Enterococcus faecalis, BT = burst time, BS = burst size, IP = infective percentage, Phage =bacteriophage, CFU = Colony forming unit, kDa = Kilodalton, OD = Optical Densities.

Reduction of ROS-HIF1α-driven glycolysis by taurine alleviates Streptococcus uberis infection

2022 ◽  
Author(s):  
Riguo Lan ◽  
Yuanyuan Zhou ◽  
Zhenglei Wang ◽  
Shaodong Fu ◽  
Yabing Gao ◽  
...  
Keyword(s):  
Bacterial Infection ◽  
Clinical Mastitis ◽  
Economic Losses ◽  
Antibiotic Resistant ◽  
Streptococcus Uberis ◽  
Promising Strategy ◽  
Resistant Strains

Antibiotic-resistant strains of Streptococcus uberis (S. uberis) frequently cause clinical mastitis resulting in enormous economic losses. The regulation of immunometabolism is a promising strategy for controlling this bacterial infection. To...

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