1
|
Born Y, Bosshard L, Duffy B, Loessner MJ, Fieseler L. Protection of Erwinia amylovora bacteriophage Y2 from UV-induced damage by natural compounds. BACTERIOPHAGE 2015; 5:e1074330. [PMID: 26904378 PMCID: PMC4743488 DOI: 10.1080/21597081.2015.1074330] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 06/23/2015] [Accepted: 07/14/2015] [Indexed: 10/23/2022]
Abstract
Bacteriophages have regained much attention as biocontrol agents against bacterial pathogens. However, with respect to stability, phages are biomolecules and are therefore sensitive to a number of environmental influences. UV-irradiation can readily inactivate phage infectivity, which impedes their potential application in the plant phyllosphere. Therefore, phages for control of Erwinia amylovora, the causative agent of fire blight, need to be protected from UV-damage by adequate measures. We investigated the protective effect of different light-absorbing substances on phage particles exposed to UV-light. For this, natural extracts from carrot, red pepper, and beetroot, casein and soy peptone in solution, and purified substances such as astaxanthin, aromatic amino acids, and Tween 80 were prepared and tested as natural sunscreens for phage. All compounds were found to significantly increase half-life of UV-irradiated phage particles and they did not negatively affect phage viability or infectivity. Altogether, a range of readily available, natural substances are suitable as UV-protectants to prevent phage particles from UV-light damage.
Collapse
Affiliation(s)
- Yannick Born
- Institute of Food and Beverage Innovation; Zurich University of Applied Sciences; Wädenswil, Switzerland
- Agroscope Wädenswil; Swiss National Competence Center for Fire Blight; Wädenswil, Switzerland
- Institute of Food; Nutrition and Health; ETH Zurich; Zürich, Switzerland
| | - Lars Bosshard
- Institute of Food; Nutrition and Health; ETH Zurich; Zürich, Switzerland
| | - Brion Duffy
- Agroscope Wädenswil; Swiss National Competence Center for Fire Blight; Wädenswil, Switzerland
- Institute of Natural Resource Sciences; Zurich University of Applied Sciences; Wädenswil, Switzerland
| | - Martin J. Loessner
- Institute of Food; Nutrition and Health; ETH Zurich; Zürich, Switzerland
| | - Lars Fieseler
- Institute of Food and Beverage Innovation; Zurich University of Applied Sciences; Wädenswil, Switzerland
- Institute of Food; Nutrition and Health; ETH Zurich; Zürich, Switzerland
| |
Collapse
|
2
|
Bloch S, Nejman-Faleńczyk B, Topka G, Dydecka A, Licznerska K, Narajczyk M, Necel A, Węgrzyn A, Węgrzyn G. UV-Sensitivity of Shiga Toxin-Converting Bacteriophage Virions Φ24B, 933W, P22, P27 and P32. Toxins (Basel) 2015; 7:3727-39. [PMID: 26402701 PMCID: PMC4591643 DOI: 10.3390/toxins7093727] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Revised: 09/14/2015] [Accepted: 09/16/2015] [Indexed: 01/19/2023] Open
Abstract
Shiga toxin-converting bacteriophages (Stx phages) are present as prophages in Shiga toxin-producing Escherichia coli (STEC) strains. Theses phages can be transmitted to previously non-pathogenic E. coli cells making them potential producers of Shiga toxins, as they bear genes for these toxins in their genomes. Therefore, sensitivity of Stx phage virions to various conditions is important in both natural processes of spreading of these viruses and potential prophylactic control of appearance of novel pathogenic E. coli strains. In this report we provide evidence that virions of Stx phages are significantly more sensitive to UV irradiation than bacteriophage λ. Following UV irradiation of Stx virions at the dose of 50 J/m2, their infectivity dropped by 1–3 log10, depending on the kind of phage. Under these conditions, a considerable release of phage DNA from virions was observed, and electron microscopy analyses indicated a large proportion of partially damaged virions. Infection of E. coli cells with UV-irradiated Stx phages resulted in significantly decreased levels of expression of N and cro genes, crucial for lytic development. We conclude that inactivation of Stx virions caused by relatively low dose of UV light is due to damage of capsids that prevents effective infection of the host cells.
Collapse
Affiliation(s)
- Sylwia Bloch
- Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland.
| | - Bożena Nejman-Faleńczyk
- Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland.
| | - Gracja Topka
- Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland.
| | - Aleksandra Dydecka
- Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland.
| | - Katarzyna Licznerska
- Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland.
| | - Magdalena Narajczyk
- Laboratory of Electron Microscopy, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland.
| | - Agnieszka Necel
- Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland.
| | - Alicja Węgrzyn
- Laboratory of Molecular Biology (affiliated with the University of Gdańsk), Polish Academy of Sciences, Wita Stwosza 59, Gdańsk 80-308, Poland.
| | - Grzegorz Węgrzyn
- Department of Molecular Biology, University of Gdańsk, Wita Stwosza 59, Gdańsk 80-308, Poland.
| |
Collapse
|
3
|
Diston D, Sinreich M, Zimmermann S, Baumgartner A, Felleisen R. Evaluation of molecular- and culture-dependent MST markers to detect fecal contamination and indicate viral presence in good quality groundwater. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:7142-51. [PMID: 25871525 DOI: 10.1021/acs.est.5b00515] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Microbial contamination of groundwater represents a significant health risk to resource users. Culture-dependent Bacteroides phage and molecular-dependent Bacteroidales 16S rRNA assays are employed in microbial source tracking (MST) studies globally, however little is known regarding how these important groups relate to each other in the environment and which is more suitable to indicate the presence of waterborne fecal pollution and human enteric viruses. This study addresses this knowledge gap by examining 64 groundwater samples from sites with varying hydrogeological properties using a MST toolbox containing two bacteriophage groups (phage infecting GB-124 and ARABA-84), and two Bacteroidales 16S rRNA markers (Hf183 and BacR); those were compared to fecal indicator bacteria, somatic coliphage, Bacteroidales 16S rRNA marker AllBac, four human enteric viruses (norovirus GI and II, enterovirus and group A rotavirus) and supplementary hydrogeological/chemical data. Bacteroidales 16S rRNA indicators offered a more sensitive assessment of both human-specific and general fecal contamination than phage indicators, but may overestimate the risk from enteric viral pathogens. Comparison with hydrogeological and land use site characteristics as well as auxiliary microbiological and chemical data proved the plausibility of the MST findings. Sites representing karst aquifers were of significantly worse microbial quality than those with unconsolidated or fissured aquifers, highlighting the vulnerability of these hydrogeological settings.
Collapse
Affiliation(s)
- D Diston
- †Federal Food Safety and Veterinary Office FSVO, Bern 3003, Switzerland
| | - M Sinreich
- ‡Federal Office for the Environment FOEN, Bern 3003, Switzerland
| | - S Zimmermann
- ‡Federal Office for the Environment FOEN, Bern 3003, Switzerland
| | - A Baumgartner
- †Federal Food Safety and Veterinary Office FSVO, Bern 3003, Switzerland
| | - R Felleisen
- †Federal Food Safety and Veterinary Office FSVO, Bern 3003, Switzerland
| |
Collapse
|
4
|
Purnell S, Ebdon J, Buck A, Tupper M, Taylor H. Bacteriophage removal in a full-scale membrane bioreactor (MBR) - Implications for wastewater reuse. WATER RESEARCH 2015; 73:109-17. [PMID: 25655318 DOI: 10.1016/j.watres.2015.01.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 01/06/2015] [Accepted: 01/10/2015] [Indexed: 05/27/2023]
Abstract
The aim of this study was to assess the potential removal efficacy of viruses in a full-scale membrane bioreactor (MBR) wastewater reuse system, using a range of indigenous and 'spiked' bacteriophages (phages) of known size and morphology. Samples were taken each week for three months from nine locations at each treatment stage of the water recycling plant (WRP) and tested for a range of microbiological parameters (n = 135). Mean levels of faecal coliforms were reduced to 0.3 CFU/100 ml in the MBR product and were undetected in samples taken after the chlorination stage. A relatively large reduction (5.3 log) in somatic coliphages was also observed following MBR treatment. However, F-specific and human-specific (GB124) phages were less abundant at all stages, and demonstrated log reductions post-MBR of 3.5 and 3.8, respectively. In 'spiking' experiments, suspended 'spiked' phages (MS2 and B-14) displayed post-MBR log reductions of 2.25 and 2.30, respectively. The removal of these suspended phages, which are smaller than the membrane pore size (0.04 μm), also highlights the possible role of the membrane biofilm as an effective additional barrier to virus transmission. The findings from this study of a full-scale MBR system demonstrate that the enumeration of several phage groups may offer a practical and conservative way of assessing the ability of MBR to remove enteric viruses of human health significance. They also suggest that phage removal in MBR systems may be highly variable and may be closely related on the one hand to both the size and morphology of the viruses and, on the other, to whether or not they are attached to solids.
Collapse
Affiliation(s)
- Sarah Purnell
- Environment and Public Health Research Group, School of Environment and Technology, University of Brighton, Cockcroft Building, Lewes Road, Brighton, BN2 4GJ, United Kingdom.
| | - James Ebdon
- Environment and Public Health Research Group, School of Environment and Technology, University of Brighton, Cockcroft Building, Lewes Road, Brighton, BN2 4GJ, United Kingdom
| | - Austen Buck
- Environment and Public Health Research Group, School of Environment and Technology, University of Brighton, Cockcroft Building, Lewes Road, Brighton, BN2 4GJ, United Kingdom
| | - Martyn Tupper
- Thames Water Utilities Limited, Clearwater Court, Vastern Road, Reading, Berkshire RG1 8DB, United Kingdom
| | - Huw Taylor
- Environment and Public Health Research Group, School of Environment and Technology, University of Brighton, Cockcroft Building, Lewes Road, Brighton, BN2 4GJ, United Kingdom
| |
Collapse
|
5
|
Karentz D. Beyond xeroderma pigmentosum: DNA damage and repair in an ecological context. A tribute to James E. Cleaver. Photochem Photobiol 2014; 91:460-74. [PMID: 25395165 DOI: 10.1111/php.12388] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 10/29/2014] [Indexed: 12/12/2022]
Abstract
The ability to repair DNA is a ubiquitous characteristic of life on Earth and all organisms possess similar mechanisms for dealing with DNA damage, an indication of a very early evolutionary origin for repair processes. James E. Cleaver's career (initiated in the early 1960s) has been devoted to the study of mammalian ultraviolet radiation (UVR) photobiology, specifically the molecular genetics of xeroderma pigmentosum and other human diseases caused by defects in DNA damage recognition and repair. This work by Jim and others has influenced the study of DNA damage and repair in a variety of taxa. Today, the field of DNA repair is enhancing our understanding of not only how to treat and prevent human disease, but is providing insights on the evolutionary history of life on Earth and how natural populations are coping with UVR-induced DNA damage from anthropogenic changes in the environment such as ozone depletion.
Collapse
Affiliation(s)
- Deneb Karentz
- Department of Biology, University of San Francisco, San Francisco, CA
| |
Collapse
|