scholarly journals A Novel Group of Promiscuous Podophages Infecting Diverse Gammaproteobacteria from River Communities Exhibits Dynamic Intergenus Host Adaptation

mSystems ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Daniel Cazares ◽  
Adrian Cazares ◽  
Wendy Figueroa ◽  
Gabriel Guarneros ◽  
Robert A. Edwards ◽  
...  
Keyword(s):  
Host Range ◽  
Host Adaptation ◽  
Natural Environments ◽  
Narrow Host Range ◽  
Diverse Communities ◽  
Broad Variety ◽  
River Communities

In natural environments, phages coexist and interact with a broad variety of bacteria, posing a conundrum for narrow-host-range phage maintenance in diverse communities. This context is rarely considered in the study of host-phage interactions, typically focused on narrow-host-range viruses and their infectivity in target bacteria isolated from sources distinct to where the phages were retrieved from.

scholarly journals Dynamics of infection in a novel group of promiscuous phages and hosts of multiple bacterial genera retrieved from river communities

2020 ◽  
Author(s):  
Daniel Cazares ◽  
Adrian Cazares ◽  
Wendy Figueroa ◽  
Gabriel Guarneros ◽  
Robert A. Edwards ◽  
...  
Keyword(s):  
Microbial Communities ◽  
Host Range ◽  
Production Efficiency ◽  
Sequence Similarity ◽  
Geographic Origin ◽  
Detailed Comparison ◽  
Natural Environments ◽  
Bacterial Strains ◽  
Narrow Host Range ◽  
Natural Systems

AbstractPhages are generally described as species- or even strain-specific viruses, implying an inherent limitation for some to be maintained and spread in diverse bacterial communities. Moreover, phage isolation and host range determination rarely consider the phage ecological context, likely biasing our notion on phage specificity. Here we identified and characterized a novel group of promiscuous phages existing in rivers by using diverse bacteria isolated from the same samples, and then used this biological system to investigate infection dynamics in distantly related hosts. We assembled a diverse collection of over 600 native bacterial strains and used them to isolate six podophages, named Atoyac, from different geographic origin and capable of infecting six genera in the Gammaproteobacteria. Atoyac phage genomes are highly similar to each other but not to those currently available in the genome and metagenome public databases. Detailed comparison of the phage’s infectivity in diverse hosts and trough hundreds of interactions revealed variation in plating efficiency amongst bacterial genera, implying a cost associated with infection of distant hosts, and between phages, despite their sequence similarity. We show, through experimental evolution in single or alternate hosts of different genera, that plaque production efficiency is highly dynamic and tends towards optimization in hosts rendering low plaque formation. Complex adaptation outcomes observed in the evolution experiments differed between highly similar phages and suggest that propagation in multiple hosts may be key to maintain promiscuity in some viruses. Our study expands our knowledge of the virosphere and uncovers bacteria-phage interactions overlooked in natural systems.ImportanceIn natural environments, phages co-exist and interact with a broad variety of bacteria, posing a conundrum for narrow-host-range phages maintenance in diverse communities. This context is rarely considered in the study of host-phage interactions, typically focused on narrow-host-range viruses and their infectivity in target bacteria isolated from sources distinct to where the phages were retrieved from. By studying phage-host interactions in bacteria and viruses isolated from river microbial communities, we show that novel phages with promiscuous host range encompassing multiple bacterial genera can be found in the environment. Assessment of hundreds of interactions in diverse hosts revealed that similar phages exhibit different infection efficiency and adaptation patterns. Understanding host range is fundamental in our knowledge of bacteria-phage interactions and their impact in microbial communities. The dynamic nature of phage promiscuity revealed in our study has implications in different aspects of phage research such as horizontal gene transfer or phage therapy.

scholarly journals Characterization of the basic replicon of pCM1, a narrow-host-range plasmid from the moderate halophile Chromohalobacter marismortui.

1995 ◽  
Vol 177 (12) ◽  
pp. 3443-3450 ◽  
Author(s):  
E Mellado ◽  
J A Asturias ◽  
J J Nieto ◽  
K N Timmis ◽  
A Ventosa
Keyword(s):  
Host Range ◽  
Moderate Halophile ◽  
Narrow Host Range

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 Evolutionary Selection of the Nuclear Localization Signal in the Viral Nucleoprotein Leads to Host Adaptation of the Genus Orthobornavirus

Viruses ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 1291
Author(s):  
Ryo Komorizono ◽  
Yukiko Sassa ◽  
Masayuki Horie ◽  
Akiko Makino ◽  
Keizo Tomonaga
Keyword(s):  
Host Range ◽  
Nuclear Localization ◽  
Nuclear Localization Signal ◽  
Mammalian Cells ◽  
Matrix Protein ◽  
Host Adaptation ◽  
Host Cells ◽  
Viral Glycoprotein ◽  
Mammalian Cell Lines ◽  
Localization Signal

Adaptation of the viral life cycle to host cells is necessary for efficient viral infection and replication. This evolutionary process has contributed to the mechanism for determining the host range of viruses. Orthobornaviruses, members of the family Bornaviridae, are non-segmented, negative-strand RNA viruses, and several genotypes have been isolated from different vertebrate species. Previous studies revealed that some genotypes isolated from avian species can replicate in mammalian cell lines, suggesting the zoonotic potential of avian orthobornaviruses. However, the mechanism by which the host specificity of orthobornaviruses is determined has not yet been identified. In this study, we found that the infectivity of orthobornaviruses is not determined at the viral entry step, mediated by the viral glycoprotein and matrix protein. Furthermore, we demonstrated that the nuclear localization signal (NLS) sequence in the viral nucleoprotein (N) has evolved under natural selection and determines the host-specific viral polymerase activity. A chimeric mammalian orthobornavirus, which has the NLS sequence of avian orthobornavirus N, exhibited a reduced propagation efficiency in mammalian cells. Our findings indicated that nuclear transport of the viral N is a determinant of the host range of orthobornaviruses, providing insights into the evolution and host adaptation of orthobornaviruses.

Novel narrow-host-range vectors for direct cloning of foreign DNA inPseudomonas

1994 ◽  
Vol 28 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Rodolphe Boivin ◽  
Guy Bellemare ◽  
Patrice Dion
Keyword(s):  
Host Range ◽  
Direct Cloning ◽  
Narrow Host Range ◽  
Foreign Dna

scholarly journals Emergence and Dissemination of Enterobacteriaceae Isolates Producing CTX-M-1-Like Enzymes in Spain Are Associated with IncFII (CTX-M-15) and Broad-Host-Range (CTX-M-1, -3, and -32) Plasmids

2006 ◽  
Vol 51 (2) ◽  
pp. 796-799 ◽  
Author(s):  
Ângela Novais ◽  
Rafael Cantón ◽  
Raquel Moreira ◽  
Luísa Peixe ◽  
Fernando Baquero ◽  
...  
Keyword(s):  
Host Range ◽  
Broad Host Range ◽  
Narrow Host Range

ABSTRACT The spread of CTX-M-1-like enzymes in Spain is associated with particular plasmids of broad-host-range IncN (bla CTX-M-32, bla CTX-M-1), IncL/M (bla CTX-M-1), and IncA/C2 (bla CTX-M-3) or narrow-host-range IncFII (bla CTX-M-15). The identical genetic surroundings of bla CTX-M-32 and bla CTX-M-1 and their locations on related 40-kb IncN plasmids indicate the in vivo evolution of this element.

A revision of species of the genus Haematoloechus Looss, 1899 (Trematoda: Haematoloechidae) from Canada and the United States

1981 ◽  
Vol 59 (9) ◽  
pp. 1836-1846 ◽  
Author(s):  
Murray J. Kennedy
Keyword(s):  
United States ◽  
Host Range ◽  
Geographical Variation ◽  
Rana Catesbeiana ◽  
Field Studies ◽  
The United States ◽  
Valid Species ◽  
Narrow Host Range ◽  
Species Groups ◽  
Degree Of Maturity

Previous experimental and field studies have shown that variations within the genus Haematoloechus may result from differences in age and degree of maturity, extent of crowding, species of host, and other factors.Based on these observations, only 6 of the 15 previously known species from Canada and the United States are considered valid. The valid species and their synonyms are as follows: Haematoloechus longiplexus Stafford, 1902; H. breviplexus Stafford, 1902; H. varioplexus Stafford, 1902 (= H. parviplexus, = H. buttensis, = H. similiplexus, = H. floedae, and H. uniplexus); H. kernensis Ingles, 1932 (= H. tumidus); H. medioplexus Stafford, 1902; and H. complexus (Seely, 1906) (= H. coloradensis, = H. confusus, = H. oxyorchis).The existence of three species groups is hypothesized. Haematoloechus longiplexus and H. breviplexus constitute one group, characterized by little geographical variation and a narrow host range. They are typically parasites of Rana catesbeiana and R. clamitans. Haematoloechus varioplexus and H. kernensis constitute the second group. These species have a wider host range and greater variation in characters purported to be specific differences. The third group includes those lung flukes which do not contain extracaecal loops (H. medioplexus and H. complexus). Of these, only H. medioplexus had little geographical variation and was found to occur in a single frog host.

scholarly journals Mice Expressing Minimally Humanized CD81 and Occludin Genes Support Hepatitis C Virus Uptake In Vivo

2016 ◽  
Vol 91 (4) ◽  
Author(s):  
Qiang Ding ◽  
Markus von Schaewen ◽  
Gabriela Hrebikova ◽  
Brigitte Heller ◽  
Lisa Sandmann ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Host Range ◽  
Amino Acid Sequences ◽  
Host Factors ◽  
Narrow Host Range ◽  
Junction Protein ◽  
Mouse Hepatocytes

ABSTRACT Hepatitis C virus (HCV) causes chronic infections in at least 150 million individuals worldwide. HCV has a narrow host range and robustly infects only humans and chimpanzees. The underlying mechanisms for this narrow host range are incompletely understood. At the level of entry, differences in the amino acid sequences between the human and mouse orthologues of two essential host factors, the tetraspanin CD81 and the tight junction protein occludin (OCLN), explain, at least in part, HCV's limited ability to enter mouse hepatocytes. We have previously shown that adenoviral or transgenic overexpression of human CD81 and OCLN facilitates HCV uptake into mouse hepatocytes in vitro and in vivo. In efforts to refine these models, we constructed knock-in mice in which the second extracellular loops of CD81 and OCLN were replaced with the respective human sequences, which contain the determinants that are critical for HCV uptake. We demonstrate that the humanized CD81 and OCLN were expressed at physiological levels in a tissue-appropriate fashion. Mice bearing the humanized alleles formed normal tight junctions and did not exhibit any immunologic abnormalities, indicating that interactions with their physiological ligands were intact. HCV entry factor knock-in mice take up HCV with an efficiency similar to that in mice expressing HCV entry factors transgenically or adenovirally, demonstrating the utility of this model for studying HCV infection in vivo. IMPORTANCE At least 150 million individuals are chronically infected with hepatitis C virus (HCV). Chronic hepatitis C can result in progressive liver disease and liver cancer. New antiviral treatments can cure HCV in the majority of patients, but a vaccine remains elusive. To gain a better understanding of the processes culminating in liver failure and cancer and to prioritize vaccine candidates more efficiently, small-animal models are needed. Here, we describe the characterization of a new mouse model in which the parts of two host factors that are essential for HCV uptake, CD81 and occludin (OCLN), which differ between mice and humans, were humanized. We demonstrate that such minimally humanized mice develop normally, express the modified genes at physiological levels, and support HCV uptake. This model is of considerable utility for studying viral entry in the three-dimensional context of the liver and to test approaches aimed at preventing HCV entry.

scholarly journals Diversity and Host Specificity Revealed by Biological Characterization and Whole Genome Sequencing of Bacteriophages Infecting Salmonella enterica

Viruses ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 854 ◽  
Author(s):  
Fong ◽  
Tremblay ◽  
Delaquis ◽  
Goodridge ◽  
Levesque ◽  
...  
Keyword(s):  
Host Range ◽  
Salmonella Enterica ◽  
Nucleotide Identity ◽  
Comparative Genomic ◽  
Broad Host Range ◽  
Natural Environments ◽  
Host Interactions ◽  
Knowledge Framework ◽  
Isolation And Characterization ◽  
Opportunistic Human Pathogen

Phages infecting members of the opportunistic human pathogen, Salmonella enterica, are widespread in natural environments and offer a potential source of agents that could be used for controlling populations of this bacterium; yet, relatively little is known about these phages. Here we describe the isolation and characterization of 45 phages of Salmonella enterica from disparate geographic locations within British Columbia, Canada. Host-range profiling revealed host-specific patterns of susceptibility and resistance, with several phages identified that have a broad-host range (i.e., able to lyse >40% of bacterial hosts tested). One phage in particular, SE13, is able to lyse 51 out of the 61 Salmonella strains tested. Comparative genomic analyses also revealed an abundance of sequence diversity in the sequenced phages. Alignment of the genomes grouped the phages into 12 clusters with three singletons. Phages within certain clusters exhibited extraordinarily high genome homology (>98% nucleotide identity), yet between clusters, genomes exhibited a span of diversity (<50% nucleotide identity). Alignment of the major capsid protein also supported the clustering pattern observed with alignment of the whole genomes. We further observed associations between genomic relatedness and the site of isolation, as well as genetic elements related to DNA metabolism and host virulence. Our data support the knowledge framework for phage diversity and phage–host interactions that are required for developing phage-based applications for various sectors, including biocontrol, detection and typing.

scholarly journals Morphological and pathogenic variations in the isolates of Rhizoctonia solani in Bangladesh

1970 ◽  
Vol 35 (3) ◽  
pp. 375-380 ◽  
Author(s):  
BK Goswami ◽  
KA Bhuiyan ◽  
IH Mian
Keyword(s):  
Rhizoctonia Solani ◽  
Host Range ◽  
Infected Plant ◽  
Agar Plate ◽  
Narrow Host Range ◽  
Ecological Zones ◽  
Plant Parts ◽  
Virulent Isolate ◽  
Wide Host Range ◽  
Avirulent Isolate

Rhizoctonia solani isolates were collected from soil of different agro-ecological zones of Bangladesh and also from infected plant parts of different crops and grasses. Collected isolates were classified into five different cluster groups on the basis of morphological and cultural characters. Five isolates taking one from each of the five different cluster groups were selected to study their pathogenicity and host range on 35 different crops. Pathogenicity and host range of the isolates were determined by planting the seeds in water agar plate infested with R. solani isolates and incubated at 25°C temperatures. After analyzing the morphological and cultural characters of the isolates, it was found that there was no relations between the isolates with respect to their origin from where they were collected. It indicated that the diversity among the isolates was not correlated with their origin. In case of host range and pathogenicity among the five selected isolates of different cluster groups, the isolate JES-16 was an avirulent isolate. The isolate SYL-30 had narrow host range and a low virulent isolate. The isolates DIN-8 and GAZ-18 possessed wide host range and might be considered as virulent isolates. The isolate GAZ-9 was a highly virulent isolate with a wide host range. Keywords: Rhizoctonia solani; morphological and pathogenic variations; isolates. DOI: 10.3329/bjar.v35i3.6443Bangladesh J. Agril. Res. 35(3) : 375-380

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