The Broad Host Range and Genetic Diversity of Mammalian and Avian Astroviruses

Abstract Background With the rise of the antimicrobial resistance between different genera and species of bacteria, Phage Therapy is becoming a more realistic and accessible option for patients with limited or no antimicrobial options. Being able to have rapid access to a collection of clinical active phages is key for rapid implementation of phage therapy. The Microbiology Department at AdventHealth Orlando is performing routine screening of environmental and patient samples for isolation of phages against non-fermenting Gram negative bacteria to develop a Phage Bank. Methods Protocols for phage isolation from environmental sources such as lakes, rivers and sewers and clinical samples were developed. A series of respiratory, throat, stool and urine samples were processed following an internal protocol that includes centrifugation, filtration and enrichment. Clinical samples were centrifugated for 10 minutes, filtered using 0.45µm centrifugation filters, seeded with targeted host bacteria (clinical isolates) and incubated at 35°C for 24 hours. The enriched samples were centrifugated and filtered for a final phage enriched solution. Screening and isolation were performed using the Gracia method over trypticase soybean agar (TSA) for plaque morphology and quantification. Host range screening of other clinical isolates of P. aeruginosa was performed using the new isolated and purified phages. Results 4 lytic phages against clinical strains of P. aeruginosa from patient with diagnosis of cystic fibrosis (CF), were isolated and purified from 4 different respiratory samples, including sputum and bronchial alveolar lavage. All phages showed phenotypical characteristics of lytic activity. 1 phage was active against 4 strains of P. aeruginosa, 1 phage was active against 2 strains of P. aeruginosa and the remaining 2 phages were active only against the initial host target strain. Conclusion With this study we demonstrated the potential use of clinical samples as source for isolating active bacteriophages against clinically significant bacteria strains. Clinical samples from vulnerable population of patients with chronic infections are part of our routine “phage-hunting” process to stock and grow our Phage Bank project for future clinical use. Disclosures All Authors: No reported disclosures

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Locally isolated broad host-range bacteriophage kills methicillin-resistant Staphylococcus aureus in an in vivo skin excisional wound model in mice

Microbial Pathogenesis ◽

10.1016/j.micpath.2021.104744 ◽

2021 ◽

Vol 152 ◽

pp. 104744

Author(s):

Manjunath Nandihalli Shetru ◽

Maribasappa Karched ◽

Dayanand Agsar

Keyword(s):

Staphylococcus Aureus ◽

Host Range ◽

Methicillin Resistant Staphylococcus Aureus ◽

Broad Host Range ◽

Methicillin Resistant ◽

Wound Model ◽

Excisional Wound

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

BMC Microbiology ◽

10.1186/s12866-020-02079-w ◽

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.

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Further Support of Conspecificity of Oak and Mango Powdery Mildew and First Report of Erysiphe quercicola and Erysiphe alphitoides on Mango in Mainland Europe

Plant Disease ◽

10.1094/pdis-01-17-0116-re ◽

2017 ◽

Vol 101 (7) ◽

pp. 1086-1093 ◽

Cited By ~ 8

Author(s):

Marie-Laure Desprez-Loustau ◽

Marie Massot ◽

Nicolas Feau ◽

Tania Fort ◽

Antonio de Vicente ◽

...

Keyword(s):

Powdery Mildew ◽

Host Range ◽

Molecular Mechanisms ◽

Single Copy ◽

Broad Host Range ◽

First Report ◽

Erysiphe Quercicola ◽

Powdery Mildews ◽

Mango Leaves ◽

Practical Implications

Mango leaves and inflorescences infected by powdery mildew in southern Spain were analyzed using multigene sequencing (ITS + 4 single-copy coding genes) to identify the causal agent. Erysiphe quercicola was detected in 97% out of 140 samples, collected in six different orchards in the Malaga region. Among these, a small proportion also yielded E. alphitoides (8% of all samples) and E. alphitoides was found alone in 3% of samples. A phylogenetic approach was completed by cross inoculations between oak and mango, which led to typical symptoms, supporting the conspecificity of oak and mango powdery mildews. To our knowledge, this is the first report of E. quercicola and E. alphitoides causing powdery mildew on mango trees in mainland Spain, and thus mainland Europe, based on unequivocal phylogenetic and biological evidence. Our study thus confirmed the broad host range of both E. quercicola and E. alphitoides. These results have practical implications in terms of the demonstrated ability for host range expansion in powdery mildews. They also open interesting prospects to the elucidation of molecular mechanisms underlying the ability to infect single versus multiple and unrelated host plants since these two closely related powdery mildew species belong to a small clade with both generalist and specialist powdery mildews.

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New Hepatitis B Virus of Cranes That Has an Unexpected Broad Host Range

Journal of Virology ◽

10.1128/jvi.77.3.1964-1976.2003 ◽

2003 ◽

Vol 77 (3) ◽

pp. 1964-1976 ◽

Cited By ~ 41

Author(s):

Alexej Prassolov ◽

Heinz Hohenberg ◽

Tatyana Kalinina ◽

Carola Schneider ◽

Lucyna Cova ◽

...

Keyword(s):

Hepatitis B Virus ◽

Hepatitis B ◽

Host Range ◽

Sequence Divergence ◽

Divergent Evolution ◽

Broad Host Range ◽

Virus Propagation ◽

Direct Dna Sequencing ◽

Duck Hepatitis ◽

B Virus

ABSTRACT All hepadnaviruses known so far have a very limited host range, restricted to their natural hosts and a few closely related species. This is thought to be due mainly to sequence divergence in the large envelope protein and species-specific differences in host components essential for virus propagation. Here we report an infection of cranes with a novel hepadnavirus, designated CHBV, that has an unexpectedly broad host range and is only distantly evolutionarily related to avihepadnaviruses of related hosts. Direct DNA sequencing of amplified CHBV DNA as well a sequencing of cloned viral genomes revealed that CHBV is most closely related to, although distinct from, Ross' goose hepatitis B virus (RGHBV) and slightly less closely related to duck hepatitis B virus (DHBV). Phylogenetically, cranes are very distant from geese and ducks and are most closely related to herons and storks. Naturally occurring hepadnaviruses in the last two species are highly divergent in sequence from RGHBV and DHBV and do not infect ducks or do so only marginally. In contrast, CHBV from crane sera and recombinant CHBV produced from LMH cells infected primary duck hepatocytes almost as efficiently as DHBV did. This is the first report of a rather broad host range of an avihepadnavirus. Our data imply either usage of similar or identical entry pathways and receptors by DHBV and CHBV, unusual host and virus adaptation mechanisms, or divergent evolution of the host genomes and cellular components required for virus propagation.

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Host range and physiologic specialization in Rhynchosporium secalis

Australian Journal of Agricultural Research ◽

10.1071/ar9740021 ◽

1974 ◽

Vol 25 (1) ◽

pp. 21 ◽

Cited By ~ 20

Author(s):

SM Ali ◽

WJR Boyd

Keyword(s):

Genetic Diversity ◽

Host Range ◽

Environmental Conditions ◽

Host Specialization ◽

Rhynchosporium Secalis ◽

Host Reaction ◽

Genetic Studies ◽

Barley Cultivars ◽

Adequate Sampling ◽

Pathogenic Variability

The pathogenic variability of isolates of R. secalis collected in Western Australia has been examined on different host genera of the Gramineae and on selected barley cultivars. Depending on the host-isolate combination and the conditions of the test, evidence has been obtained of inter- and intra-isolate variability in both host reaction and isolate pathogenicity. This complicates definitive interpretation of the results, militates against identification of conventional 'races' of the pathogen and shows that R. secalis does not exhibit strict host specialization. Hosts which consistently express resistance or susceptibility under different environmental conditions, and isolates which express their pathogenic characteristics consistently, have been identified. The need for more precise genetic studies and adequate sampling of genetic diversity is emphasized.

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Construction of a broad-host-range pneumococcal promoter-probe plasmid

Gene ◽

10.1016/0378-1119(90)90455-z ◽

1990 ◽

Vol 90 (1) ◽

pp. 163-167 ◽

Cited By ~ 11

Author(s):

Eduardo Diaz ◽

JoséL. Garcia

Keyword(s):

Host Range ◽

Broad Host Range ◽

Promoter Probe

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