Fight evolution with evolution: plasmid‐dependent phages with a wide host range prevent the spread of antibiotic resistance

Due to the rapid spread of antibiotic resistance, and the difficulties of treating biofilm-associated infections, alternative treatments for S. aureus infections are urgently needed. We tested the lytic activity of several wild type phages against a panel of 110 S. aureus strains (MRSA/MSSA) composed to reflect the prevalence of S. aureus clonal complexes in human infections. The plaquing host ranges (PHR) of the wild type phages were in the range of 51% to 60%. We also measured what we called the kinetic host range (KHR), i.e., the percentage of strains for which growth in suspension was suppressed for 24 h. The KHR of the wild type phages ranged from 2% to 49%, substantially lower than the PHRs. To improve the KHR and other key pharmaceutical properties, we bred the phages by mixing and propagating cocktails on a subset of S. aureus strains. These bred phages, which we termed evolution-squared (ε2) phages, have broader KHRs up to 64% and increased virulence compared to the ancestors. The ε2-phages with the broadest KHR have genomes intercrossed from up to three different ancestors. We composed a cocktail of three ε2-phages with an overall KHR of 92% and PHR of 96% on 110 S. aureus strains and called it PM-399. PM-399 has a lower propensity to resistance formation than the standard of care antibiotics vancomycin, rifampicin, or their combination, and no resistance was observed in laboratory settings (detection limit: 1 cell in 1011). In summary, ε2-phages and, in particular PM-399, are promising candidates for an alternative treatment of S. aureus infections.

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Wide host range of murine sarcoma virus

International Journal of Cancer ◽

10.1002/ijc.2910120321 ◽

1973 ◽

Vol 12 (3) ◽

pp. 734-741 ◽

Cited By ~ 8

Author(s):

Johng S. Rhim ◽

Mina L. Vernon ◽

Fuw G. Duh ◽

Robert J. Huebner

Keyword(s):

Host Range ◽

Wide Host Range ◽

Murine Sarcoma Virus ◽

Sarcoma Virus ◽

Murine Sarcoma

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In Vitro-Transcribed Chrysanthemum stunt viroid RNA Is Infectious to Chrysanthemum and Other Plants

Phytopathology ◽

10.1094/phyto-99-1-0058 ◽

2009 ◽

Vol 99 (1) ◽

pp. 58-66 ◽

Cited By ~ 23

Author(s):

Yosuke Matsushita ◽

Kumar K. R. Penmetcha

Keyword(s):

Host Range ◽

Noncoding Rna ◽

Chrysanthemum Stunt Viroid ◽

Stunt Viroid ◽

Wide Host Range

Chrysanthemum stunt viroid (CSVd), a noncoding RNA, is known to cause chrysanthemum stunt disease, which affects the yield of flowers. To gain insights into CSVd replication, infection, and the reasons for the spreading of CSVd disease in chrysanthemum plants, we prepared linear CSVd RNA and analyzed its ability to cause disease in chrysanthemum plants. We found that linear CSVd replicated as efficiently as CSVd RNA isolated from the infected chrysanthemum plants. Additionally, the linear CSVd RNA was evaluated for its ability to infect other plants as well, which revealed that CSVd has a wide host range for its replication. Importantly, the CSVd isolated from these hosts is infectious to chrysanthemum plants, and thus potentially contributes to the spreading of the disease to chrysanthemum plants.

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Isolation and Characterization of a Wide Host Range Phage from a Mesophilic Starter Culture

MILK the vital force ◽

10.1007/978-94-009-3733-8_90 ◽

1986 ◽

pp. 105-105

Author(s):

A. von Wright ◽

T. Saarinen ◽

S. Sivelä

Keyword(s):

Host Range ◽

Starter Culture ◽

Isolation And Characterization ◽

Wide Host Range

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First interception of the greenhouse pest Echinothrips americanus Morgan, 1913 (Thysanoptera: Thripidae) in Slovakia

Plant Protection Science ◽

10.17221/29/2008-pps ◽

2009 ◽

Vol 44 (No. 4) ◽

pp. 155-159 ◽

Cited By ~ 9

Author(s):

L. Varga ◽

P.J. Fedor

Keyword(s):

North America ◽

Host Range ◽

Botanical Garden ◽

European Countries ◽

Pest Species ◽

Wide Host Range ◽

Short Time ◽

And Control

<i>Echinothrips americanus</i> Morgan, 1913, is one of the pest species that expanded their area of distribution in a relatively short time. Being native to the eastern parts of North America, its first European interception was recorded in 1989. Since then it has invaded greenhouses in most European countries, including Slovakia, where it was first recorded in inspected material at the Botanical garden in Košice. As a polyphagous thrips with a wide host range it may induce damage mainly on ornamentals, although if low in numbers it can be easily overlooked. The species is a suitable example where preventive steps against its spread have not been sufficient enough which, therefore, demands further monitoring. Remarks on morphology, identification, economical importance and control are also given.

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Thanatephorus Cucumeris (Rhizoctonia Solani), a Species Complex of Wide Host Range

Genetics of Plant Pathogenic Fungi - Advances in Plant Pathology ◽

10.1016/b978-0-12-033706-4.50040-2 ◽

1988 ◽

pp. 535-552 ◽

Cited By ~ 48

Author(s):

G.C. Adams

Keyword(s):

Rhizoctonia Solani ◽

Host Range ◽

Species Complex ◽

Thanatephorus Cucumeris ◽

Wide Host Range

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Backyard Farms Represent a Source of Wide Host Range Salmonella Phages That Lysed the Most Common Salmonella Serovars

Journal of Food Protection ◽

10.4315/0362-028x.jfp-17-075 ◽

2018 ◽

Vol 81 (2) ◽

pp. 272-278 ◽

Cited By ~ 4

Author(s):

DÁCIL RIVERA ◽

VIVIANA TOLEDO ◽

FRANCISCA DI PILLO ◽

FERNANDO DUEÑAS ◽

RODOLFO TARDONE ◽

...

Keyword(s):

Host Range ◽

Salmonella Enteritidis ◽

Genetic Relatedness ◽

Production Systems ◽

Lytic Cycle ◽

Salmonella Infections ◽

Wide Host Range ◽

Wide Range ◽

Salmonella Serovars ◽

Phage Isolation

ABSTRACT The genus Salmonella has more than 2,600 serovars, and this trait is important when considering interventions for Salmonella control. Bacteriophages that are used for biocontrol must have an exclusively lytic cycle and the ability to lyse several Salmonella serovars under a wide range of environmental conditions. Salmonella phages were isolated and characterized from 34 backyard production systems (BPSs) with a history of Salmonella infections. BPSs were visited once, and cloacal or fecal samples were processed for phage isolation. Four hosts, Salmonella serovars Enteritidis, Heidelberg, Infantis, and Typhimurium, were used for phage isolation. The host range of the phages was later characterized with a panel of 23 Salmonella serovars (serovar diversity set) and 31 isolates obtained from the same farms (native set). Genetic relatedness for 10 phages with a wide host range was characterized by restriction fragment length polymorphism, and phages clustered based on the host range. We purified 63 phages, and 36 phage isolates were obtained on Salmonella Enteritidis, 16 on Salmonella Heidelberg, and 11 on Salmonella Infantis. Phages were classified in three clusters: (i) phages with a wide host range (cluster I), (ii) phages that lysed the most susceptible Salmonella serovars (serogroup D) and other isolates (cluster II), and (iii) phages that lysed only isolates of serogroup D (cluster III). The most susceptible Salmonella serovars were Enteritidis, Javiana, and Dublin. Seven of 34 farms yielded phages with a wide host range, and these phages had low levels of genetic relatedness. Our study showed an adaptation of the phages in the sampled BPSs to serogroup D Salmonella isolates and indicated that isolation of Salmonella phages with wide host range differs by farm. A better understanding of the factors driving the Salmonella phage host range could be useful when designing risk-based sampling strategies to obtain phages with a wide lytic host range for biocontrol purposes.

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

Bangladesh Journal of Agricultural Research ◽

10.3329/bjar.v35i3.6443 ◽

1970 ◽

Vol 35 (3) ◽

pp. 375-380 ◽

Cited By ~ 1

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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