Isolation and properties of a bacteriophage lytic for a wide range of pseudomonads

1971 ◽  
Vol 17 (5) ◽  
pp. 677-682 ◽  
Author(s):  
R. A. Kelln ◽  
R. A. J. Warren
Keyword(s):  
Latent Period ◽  
Pseudomonas Fluorescens ◽  
Host Range ◽  
Burst Size ◽  
Broad Host Range ◽  
Lytic Bacteriophage ◽  
Bacterial Strains ◽  
Short Tail ◽  
Wide Range ◽  
Different Strains

The lytic bacteriophage ø-S1 was isolated from sewage using a strain of Pseudomonas fluorescens as host. It had a hexagonal head 60 nm in diameter and a short tail 30 nm long. ø-S1 had a broad host range, lysing strains from 10 biotypes of Pseudomonads. Although the latent period was fairly constant for the bacterial strains tested, the burst size varied considerably. The rate of adsorption of the phage to different strains also varied considerably.

scholarly journals TSP, a virulent Podovirus can control the growth of Staphylococcus aureus till 12 hours

2021 ◽  
Author(s):  
Rabia Tabassum ◽  
Iqbal Ahmed Alvi ◽  
Muhammad Asif ◽  
Abdul Basit ◽  
Shafiq ur Rehman
Keyword(s):  
Staphylococcus Aureus ◽  
Latent Period ◽  
Genome Sequence ◽  
Burst Size ◽  
Gc Content ◽  
Comparative Genomic ◽  
Broad Host Range ◽  
Lytic Bacteriophage ◽  
Short Latent Period ◽  
Promising Therapeutic Approach

Abstract Methicillin-resistant Staphylococcus aureus (MRSA) is a prevailing nosocomial pathogen that causes a large number of diseases in healthcare and community settings. The MRSA causes infections in different tissues of immunocompromised individuals leading to increased morbidity and mortality. It possess various virulence mechanisms to show resistance against to a lot of beta-lactam antibiotics. To tackle this emerging issue of MRSA, there is an urgent need of antibiotic alternatives and utilizing lytic bacteriophages is one of the best promising therapeutic approach. In the present study, a lytic bacteriophage TSP was isolated from hospital wastewater against MRSA. Its morphology, physiology, host specificity, burst size and lytic spectrum were determined and complete genome sequence was analyzed. TSP phage efficiently inhibit bacterial growth for up to 12 hours. TSP phage showed broad lytic spectrum against clinical isolates of MRSA (78%) and MSSA (37%). It showed stability at varying temperatures (25ºC, 37ºC) and pH (5–9), while its maximum storage stability was observed at 4ºC. It had short latent period (20min) and high burst size (103 PFU/ infected cell). TSP genome sequence and restriction analysis revealed that its genome is linear having 17,987 bp in length with an average GC content of 29.7%. The TSP genome showed 98% similarity to S aureus phages SCH1, SCH11 and vB SauP-436A1. According to comparative genomic analysis and phylogenetic tree analysis, TSP phage can be considered as a member of genus “P68viruses”. The strong lytic activity, broad host range and short latent period along with absence of any lysogenic and toxic genes make TSP a very good candidate for phage therapy against MRSA infections if prove safe during in vivo studies.

scholarly journals Revealing biophysical properties of KfrA-type proteins as a novel class of cytoskeletal, coiled-coil plasmid-encoded proteins

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
M. Adamczyk ◽  
E. Lewicka ◽  
R. Szatkowska ◽  
H. Nieznanska ◽  
J. Ludwiczak ◽  
...  
Keyword(s):  
Dna Binding ◽  
Host Range ◽  
Coiled Coil ◽  
Amino Acid Sequences ◽  
Broad Host Range ◽  
Biophysical Properties ◽  
Dna Binding Sites ◽  
In Silico Studies ◽  
Wide Range

Abstract Background DNA binding KfrA-type proteins of broad-host-range bacterial plasmids belonging to IncP-1 and IncU incompatibility groups are characterized by globular N-terminal head domains and long alpha-helical coiled-coil tails. They have been shown to act as transcriptional auto-regulators. Results This study was focused on two members of the growing family of KfrA-type proteins encoded by the broad-host-range plasmids, R751 of IncP-1β and RA3 of IncU groups. Comparative in vitro and in silico studies on KfrAR751 and KfrARA3 confirmed their similar biophysical properties despite low conservation of the amino acid sequences. They form a wide range of oligomeric forms in vitro and, in the presence of their cognate DNA binding sites, they polymerize into the higher order filaments visualized as “threads” by negative staining electron microscopy. The studies revealed also temperature-dependent changes in the coiled-coil segment of KfrA proteins that is involved in the stabilization of dimers required for DNA interactions. Conclusion KfrAR751 and KfrARA3 are structural homologues. We postulate that KfrA type proteins have moonlighting activity. They not only act as transcriptional auto-regulators but form cytoskeletal structures, which might facilitate plasmid DNA delivery and positioning in the cells before cell division, involving thermal energy.

scholarly journals Isolation of the Novel Phage PHB09 and Its Potential Use against the Plant Pathogen Pseudomonas syringae pv. actinidiae

Viruses ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2275
Author(s):  
Yanxi Liu ◽  
Mengjiao Liu ◽  
Ran Hu ◽  
Jun Bai ◽  
Xiaoqing He ◽  
...  
Keyword(s):  
Host Range ◽  
Pseudomonas Syringae ◽  
Management Strategies ◽  
Lytic Bacteriophage ◽  
Bacterial Canker ◽  
Isolation And Identification ◽  
Narrow Host Range ◽  
Development Of Resistance ◽  
Wide Range ◽  
Complete Genome Sequence Analysis

Bacteriophages are viruses that specifically infect target bacteria. Recently, bacteriophages have been considered potential biological control agents for bacterial pathogens due to their host specificity. Pseudomonas syringae pv. actinidiae (Psa) is a reemerging pathogen that causes bacterial canker of kiwifruit (Actinidia sp.). The economic impact of this pest and the development of resistance to antibiotics and copper sprays in Psa and other pathovars have led to investigation of alternative management strategies. Phage therapy may be a useful alternative to conventional treatments for controlling Psa infections. Although the efficacy of bacteriophage φ6 was evaluated for the control of Psa, the characteristics of other DNA bacteriophages infecting Psa remain unclear. In this study, the PHB09 lytic bacteriophage specific to Psa was isolated from kiwifruit orchard soil. Extensive host range testing using Psa isolated from kiwifruit orchards and other Pseudomonas strains showed PHB09 has a narrow host range. It remained stable over a wide range of temperatures (4–50 °C) and pH values (pH 3–11) and maintained stability for 50 min under ultraviolet irradiation. Complete genome sequence analysis indicated PHB09 might belong to a new myovirus genus in Caudoviricetes. Its genome contains a total of 94,844 bp and 186 predicted genes associated with phage structure, packaging, host lysis, DNA manipulation, transcription, and additional functions. The isolation and identification of PHB09 enrich the research on Pseudomonas phages and provide a promising biocontrol agent against kiwifruit bacterial canker.

scholarly journals A65 Characterization of endolysin gene of bacteriophages infecting Listeria spp. isolated from dairy industry wastewater

2019 ◽  
Vol 5 (Supplement_1) ◽  
Author(s):  
Blanco Fernández ◽  
M E Barrios ◽  
R V Cammarata ◽  
C Torres ◽  
V A Mbayed
Keyword(s):  
Host Range ◽  
High Titer ◽  
Dairy Industry ◽  
Foodborne Pathogen ◽  
Dairy Farm ◽  
Restriction Enzymes ◽  
Invasive Disease ◽  
Broad Host Range ◽  
Wide Range ◽  
Industry Wastewater

Abstract Bacteriophages and their endolysins, enzymes that degrade the cell walls of bacteria, are emerging as alternative tools to detect and inhibit growth of pathogen bacteria. Listeria monocytogenes is a foodborne pathogen that causes listeriosis, a serious invasive disease that affects both humans and a wide range of animals. Listeria spp. are ubiquitous in the dairy farm environment and could be present in dairy-processing plants and wastewater. All Listeria-specific bacteriophages found to date are members of the Caudovirales, of the Siphoviridae or Myoviridae families. Myophages infecting Listeria have been recently classified by the ICTV in the Spounavirinae subfamily, as well as in the P100 virus genus. The aim of this work was to isolate Listeria spp. bacteriophages and their endolysin codifying genes from wastewater of a dairy industry. Wastewater with and without treatment was sampled during the course of a year, and isolation of bacteriophages was performed after an enrichment step using as hosts L. innocua, L. ivanovii, and L. monocytogenes serotypes 1/2a, 1/2b, and 4b. Bacteriophages infecting L. innocua and L. ivanovii were isolated (n = 24) from 3 out of 12 samples. Bacteriophages were purified, and the host range was determined using spot test and EOP against five collection strains and several field isolates of Listeria spp. Two bacteriophages of narrow and broad host range, vB_Lino_VEfB7, and vB_Liva_VAfA18, were selected for further characterization. High titer stocks of bacteriophages were purified by centrifugation with ammonium acetate, and morphological information on the purified bacteriophages was obtained by negative staining and transmission electronic microscopy. Their morphology, size, and contractile tails indicated that these bacteriophages belonged to the Myoviridae family. Bacteriophage genomes were extracted using phenol-chloroform, followed by ethanol precipitation, and tested by digestion with RNAsa A and DNAse I. RFLP was performed, digesting genomes with restriction enzymes HindIII and NcoI. Consistent with the morphological findings, bacteriophages contained dsDNA genomes but showed different RFLP patterns. A PCR designed to amplify conserved domains of endolysins—PGRP and CwlA—was applied to characterize this gene. Another PCR was designed to amplify the complete endolysin gene, and the complete sequence of this gene was obtained and analyzed. Substitution model selection and a maximum likelihood phylogenetic tree of the endolysin gene was carried out using IQ-Tree software. The sequences of the endolysin gene indicated that the codified enzyme is an N-acetyl-muramoyl-L-alanine amidase, related to A511 and P100 species of the recently described P100virus genus. Further evolutionary analyses are needed to evaluate their belonging to this species or their taxonomy within this genus.

Limits to the host range of the highly polyphagous tephritid fruit fly Anastrepha ludens in its natural habitat

2015 ◽  
Vol 105 (6) ◽  
pp. 743-753 ◽  
Author(s):  
A. Birke ◽  
E. Acosta ◽  
M. Aluja
Keyword(s):  
Host Range ◽  
Natural Habitat ◽  
Fruit Fly ◽  
Natural Host ◽  
Pupal Weight ◽  
Anastrepha Ludens ◽  
Broad Host Range ◽  
Ripe Fruit ◽  
Natural Conditions ◽  
Wide Range

AbstractAnastepha ludens (Diptera: Tephritidae) is a highly polyphagous fruit fly that is able to develop in a wide range of hosts. Understanding the limits of this pest's host range could provide valuable information for pest management and plant breeding for pest resistance. Previous studies have shown that guavas (Psidium guajava (Myrtaceae) L.), are not attacked under natural conditions by A. ludens. To understand this phenomenon, guavas were exposed to natural infestation by A. ludens and to other fruit fly species that infest guavas in nature (Anastrepha striata Schiner, Anastepha fraterculus (Wiedemann), Anastepha obliqua (Macquart)). Once the susceptible phenological stage of guavas was determined, fruit infestation levels were compared between A. ludens and A. striata. Choice and non-choice tests were performed under field-cage conditions. Under field conditions, guavas were susceptible to A. striata and A. fraterculus attack all the way from when fruit was undeveloped to when fruit began to ripen. No infestation by A. ludens was recorded under natural conditions. Similar results were obtained when forced exposures were performed, indicating that unripe guavas were preferred by A. striata over ripe fruit, and that infestation rates were higher at early fruit maturity stages. Under forced oviposition conditions, A. ludens larvae were unable to develop in unripe guavas but did so in fully ripe fruit. However, A. ludens fitness parameters were dramatically affected, exhibiting reduced survival and reduced pupal weight compared to conspecifics that developed in a natural host, grapefruit. We confirm that P. guajava should not be treated as a natural host of this pestiferous species, and suggest that both behavioral aspects and the fact that larvae are unable to adequately develop in this fruit, indeed represent clear limits to A. ludens's broad host range.

scholarly journals Characterization of E coli phage isolated from sewage

2010 ◽  
Vol 9 (2) ◽  
pp. 45 ◽  
Author(s):  
G.A. Al-Mola, and I. H. Al-Yassari
Keyword(s):  
Statistical Analysis ◽  
Latent Period ◽  
Burst Size ◽  
Host Cells ◽  
Effect Of Temperature ◽  
Lytic Bacteriophage ◽  
Bacterial Cells ◽  
Dilution Factor ◽  
Countable Number ◽  
Phage Titre

Bacteriophage are viruses that infect bacterial cells. as with all viruses, phage are nonliving agents and thus require the use of the host‟s metabolic processes to replicate itself. in this study, the phage of interest are those that infect and lyses E. colt host cells. when phage are released from the ruptured host, distinct zones of clearing (plaques) form. the original E. colt host cells for this experiment came from a sample of raw sewage. in order to obtain the bacteriophage, a procedure of enrichment, isolation, dilution and seeding was followed, the presence of distinct plaques indicated that lytic bacteriophage had been successfully amplified, separated and grown.This study included determination of phage titre, latent period , rise period and the burst size of the phage and effect some of factor on phage titre such as (temperature, ether and chloroform) .for determination ofhage titre used series of dilutions(10-1, 10-2, 10-3, 10-4, 10-4, 10-6, 10-7, 10-8, 10-9) the dilution factor gave the best countable number of plaques is(103). this dilution factor was then used for all other experiments, the latent period , rise period and the burst size of the phage are determined by countable number of plaques and phage titre(titer: plaque-forming unit(p.f.u) during 10,20,30,40,50, and 60 minutes . it was (4.7x105 „ 5.3x105 and 6.0x105)during 1O,20and30minutes respectively in the latent period ,but it was (8.5x105 8.9x10‟ 9.3x105)during 40,50,and 60 minutes respectively in the rise period .then the burst size of the phage is counted by the ratio of the phage titer after rise period to that during the latent period it was(1.67).This study also included effect of temperature on phage titre the statistical analysis was significantly increase P<0.05 in phage titre at the temperature37 C° comparing with phage titre at the temperature 50 C° and phage titre at the temperature 65 C°. effects of ether and chloroform on number of plaques and phage titre during 5,10,15 ,20,25 ,30,35 and 40 minutes it was(0.7x105 , 0.3x105 , 0 , 0 , 0 , 0, 0 and 0) respectively in ether sensitivity, but the phage titre in chloroform sensitivity was completely inactivated by chloroform treatment, the statistical analysis (freedom degree ( 2,21 ) and F value=52.60 was high] significant increase (P<0.05) in phage titre in normal saline comparing with phage titre in ether and chloroform sensitivity

scholarly journals Isolation of Polyvalent Bacteriophages by Sequential Multiple-Host Approaches

2015 ◽  
Vol 82 (3) ◽  
pp. 808-815 ◽  
Author(s):  
Pingfeng Yu ◽  
Jacques Mathieu ◽  
Mengyan Li ◽  
Zhaoyi Dai ◽  
Pedro J. J. Alvarez
Keyword(s):  
Host Range ◽  
Pseudomonas Syringae ◽  
Burst Size ◽  
Broad Host Range ◽  
Ecological Significance ◽  
Content Type ◽  
Narrow Host Range ◽  
Isolation Methods ◽  
Culture Independent ◽  
K 12

ABSTRACTMany studies on phage biology are based on isolation methods that may inadvertently select for narrow-host-range phages. Consequently, broad-host-range phages, whose ecological significance is largely unexplored, are consistently overlooked. To enhance research on such polyvalent phages, we developed two sequential multihost isolation methods and tested both culture-dependent and culture-independent phage libraries for broad infectivity. Lytic phages isolated from activated sludge were capable of interspecies or even interorder infectivity without a significant reduction in the efficiency of plating (0.45 to 1.15). Two polyvalent phages (PX1 of thePodoviridaefamily and PEf1 of theSiphoviridaefamily) were characterized in terms of adsorption rate (3.54 × 10−10to 8.53 × 10−10ml/min), latent time (40 to 55 min), and burst size (45 to 99 PFU/cell), using different hosts. These phages were enriched with a nonpathogenic host (Pseudomonas putidaF1 orEscherichia coliK-12) and subsequently used to infect model problematic bacteria. By using a multiplicity of infection of 10 in bacterial challenge tests, >60% lethality was observed forPseudomonas aeruginosarelative to uninfected controls. The corresponding lethality forPseudomonas syringaewas ∼50%. Overall, this work suggests that polyvalent phages may be readily isolated from the environment by using different sequential hosts, and this approach should facilitate the study of their ecological significance as well as enable novel applications.

scholarly journals Characterization of vB_StuS_MMDA13, a Newly Discovered Bacteriophage Infecting the Agar-Degrading Species Sphingomonas turrisvirgatae

Viruses ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 894
Author(s):  
Pasquale Marmo ◽  
Maria Cristina Thaller ◽  
Gustavo Di Lallo ◽  
Lucia Henrici De Angelis ◽  
Noemi Poerio ◽  
...  
Keyword(s):  
Burst Size ◽  
Latency Period ◽  
Biosynthetic Gene Cluster ◽  
Open Reading Frames ◽  
Lytic Bacteriophage ◽  
Coding Region ◽  
Narrow Host Range ◽  
Physiological Characterization ◽  
Wide Range ◽  
Valuable Compounds

Members of Sphingomonas genus have gained a notable interest for their use in a wide range of biotechnological applications, ranging from bioremediation to the production of valuable compounds of industrial interest. To date, knowledge on phages targeting Sphingomonas spp. are still scarce. Here, we describe and characterize a lytic bacteriophage, named vB_StuS_MMDA13, able to infect the Sphingomonas turrisvirgatae MCT13 type strain. Physiological characterization demonstrated that vB_StuS_MMDA13 has a narrow host range, a long latency period, a low burst size, and it is overall stable to both temperature and pH variations. The phage has a double-stranded DNA genome of 63,743 bp, with 89 open reading frames arranged in two opposite arms separated by a 1186 bp non-coding region and shows a very low global similarity to any other known phages. Interestingly, vB_StuS_MMDA13 is endowed with an original nucleotide modification biosynthetic gene cluster, which greatly differs from those of its most closely related phages of the Nipunavirus genus. vB_StuS_MMDA13 is the first characterized lytic bacteriophage of the Siphoviridae family infecting members of the Sphingomonas genus.

scholarly journals Broad-Host-Range Yersinia Phage PY100: Genome Sequence, Proteome Analysis of Virions, and DNA Packaging Strategy

2007 ◽  
Vol 190 (1) ◽  
pp. 332-342 ◽  
Author(s):  
Dominik Schwudke ◽  
Asgar Ergin ◽  
Kathrin Michael ◽  
Sven Volkmar ◽  
Bernd Appel ◽  
...  
Keyword(s):  
Host Range ◽  
Proteome Analysis ◽  
Open Reading Frames ◽  
Broad Host Range ◽  
Lytic Bacteriophage ◽  
Coding Region ◽  
Putative Gene ◽  
Packaging Strategy ◽  
Virion Particles ◽  
Tail Proteins

ABSTRACT PY100 is a lytic bacteriophage with a broad host range within the genus Yersinia. The phage forms plaques on strains of the three human pathogenic species Yersinia enterocolitica, Y. pseudotuberculosis, and Y. pestis at 37°C. PY100 was isolated from farm manure and intended to be used in phage therapy trials. PY100 has an icosahedral capsid containing double-stranded DNA and a contractile tail. The genome consists of 50,291 bp and is predicted to contain 93 open reading frames (ORFs). PY100 gene products were found to be homologous to the capsid proteins and proteins involved in DNA metabolism of the enterobacterial phage T1; PY100 tail proteins possess homologies to putative tail proteins of phage AaΦ23 of Actinobacillus actinomycetemcomitans. In a proteome analysis of virion particles, 15 proteins of the head and tail structures were identified by mass spectrometry. The putative gene product of ORF2 of PY100 shows significant homology to the gene 3 product (small terminase subunit) of Salmonella phage P22 that is involved in packaging of the concatemeric phage DNA. The packaging mechanism of PY100 was analyzed by hybridization and sequence analysis of DNA isolated from virion particles. Newly replicated PY100 DNA is cut initially at a pac recognition site, which is located in the coding region of ORF2.

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