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Arisaka F. Isolation and grouping of RNA phages by Itaru Watanabe et al. (1967). Proc Jpn Acad Ser B Phys Biol Sci 2024; 100:253-263. [PMID: 38599846 DOI: 10.2183/pjab.100.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
I. Watanabe et al. isolated approximately 30 strains of RNA phages from various parts of Japan. To isolate RNA phages, they assessed the infection specificity of male Escherichia coli and RNase sensitivity. They found that the isolated strains of RNA phages could be serologically separated into three groups. Furthermore, most of them were serologically related, and the antiphage rabbit serum prepared by one of these phages neutralized most of the other phages. The only serologically unrelated phage was the RNA phage Qβ, which was isolated at the Institute for Virus Research, Kyoto University, in 1961.
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Nguyen HM, Watanabe S, Sharmin S, Kawaguchi T, Tan XE, Wannigama DL, Cui L. RNA and Single-Stranded DNA Phages: Unveiling the Promise from the Underexplored World of Viruses. Int J Mol Sci 2023; 24:17029. [PMID: 38069353 PMCID: PMC10707117 DOI: 10.3390/ijms242317029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 11/26/2023] [Accepted: 11/28/2023] [Indexed: 12/18/2023] Open
Abstract
RNA and single-stranded DNA (ssDNA) phages make up an understudied subset of bacteriophages that have been rapidly expanding in the last decade thanks to advancements in metaviromics. Since their discovery, applications of genetic engineering to ssDNA and RNA phages have revealed their immense potential for diverse applications in healthcare and biotechnology. In this review, we explore the past and present applications of this underexplored group of phages, particularly their current usage as therapeutic agents against multidrug-resistant bacteria. We also discuss engineering techniques such as recombinant expression, CRISPR/Cas-based genome editing, and synthetic rebooting of phage-like particles for their role in tailoring phages for disease treatment, imaging, biomaterial development, and delivery systems. Recent breakthroughs in RNA phage engineering techniques are especially highlighted. We conclude with a perspective on challenges and future prospects, emphasizing the untapped diversity of ssDNA and RNA phages and their potential to revolutionize biotechnology and medicine.
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Affiliation(s)
- Huong Minh Nguyen
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan; (H.M.N.); (S.W.); (S.S.); (T.K.); (X.-E.T.)
| | - Shinya Watanabe
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan; (H.M.N.); (S.W.); (S.S.); (T.K.); (X.-E.T.)
| | - Sultana Sharmin
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan; (H.M.N.); (S.W.); (S.S.); (T.K.); (X.-E.T.)
| | - Tomofumi Kawaguchi
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan; (H.M.N.); (S.W.); (S.S.); (T.K.); (X.-E.T.)
| | - Xin-Ee Tan
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan; (H.M.N.); (S.W.); (S.S.); (T.K.); (X.-E.T.)
| | - Dhammika Leshan Wannigama
- Department of Infectious Diseases and Infection Control, Yamagata Prefectural Central Hospital, Yamagata 990-2292, Yamagata, Japan;
| | - Longzhu Cui
- Division of Bacteriology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke 329-0498, Tochigi, Japan; (H.M.N.); (S.W.); (S.S.); (T.K.); (X.-E.T.)
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3
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He Z, Parra B, Nesme J, Smets BF, Dechesne A. Quantification and fate of plasmid-specific bacteriophages in wastewater: Beyond the F-coliphages. Water Res 2022; 227:119320. [PMID: 36395568 DOI: 10.1016/j.watres.2022.119320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/26/2022] [Accepted: 11/02/2022] [Indexed: 06/16/2023]
Abstract
Plasmid-specific bacteriophages specifically infect bacteria carrying conjugal plasmids. While wastewater has been used as isolation source for such phages, to date, only the distribution and ecology of RNA phages specific to the F plasmid have been described, because they serve as a water quality indicator. Yet, several other plasmid classes have higher clinical and ecological relevance, and the distribution, fate, and ecology of the phages that target them remain uncharacterized. We aimed to (i) provide an experimental platform to quantify the abundance of plasmid-specific phages applicable to several different conjugal plasmid classes, (ii) describe the distribution of such phages in wastewater systems, and (iii) relate their abundance to plasmid abundance and to municipal wastewater treatment processes. We introduced four model conjugal plasmids, belonging to incompatibility groups IncP-1, IncN, IncHI1, or IncF into an avirulent Salmonella enterica strain, for which somatic phages are at low abundance in wastewater. These strains were used in double layer agar assays with waters from contrasting sources. Plasmid-specific phages were common in wastewater but rare in river water. Hospital wastewater contained significantly more IncP-1-, but fewer IncF- and IncN- specific phages than domestic wastewater. This pattern did not match that of plasmid abundance estimated by Inc group targeting high-throughput quantitative PCR. The comparison between influent and effluent of wastewater treatment plants revealed a reduction in phage concentration by ca. 2 log, without significant contribution of primary settling. Overall, the ubiquity of these phages hints at their importance for plasmid ecology, and can provide opportunities in water quality monitoring and in ecological management of mobile resistance genes.
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Affiliation(s)
- Zhiming He
- Technical University of Denmark, Department of Environmental and Resource Engineering, Bygningstorvet Bygning 115, 2800 Kgs. Lyngby, Denmark
| | - Boris Parra
- Technical University of Denmark, Department of Environmental and Resource Engineering, Bygningstorvet Bygning 115, 2800 Kgs. Lyngby, Denmark
| | - Joseph Nesme
- University of Copenhagen, Department of Biology, Section of Microbiology, Universitetsparken 15, DK-2100 Copenhagen Ø, Denmark
| | - Barth F Smets
- Technical University of Denmark, Department of Environmental and Resource Engineering, Bygningstorvet Bygning 115, 2800 Kgs. Lyngby, Denmark
| | - Arnaud Dechesne
- Technical University of Denmark, Department of Environmental and Resource Engineering, Bygningstorvet Bygning 115, 2800 Kgs. Lyngby, Denmark.
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4
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Gyawali P, Devane M, Scholes P, Hewitt J. Application of crAssphage, F-RNA phage and pepper mild mottle virus as indicators of human faecal and norovirus contamination in shellfish. Sci Total Environ 2021; 783:146848. [PMID: 33865125 DOI: 10.1016/j.scitotenv.2021.146848] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 06/12/2023]
Abstract
Shellfish growing waters contaminated with inadequately treated human wastewater is a major source of norovirus in shellfish and poses a significant human health risk to consumers. Microbial source tracking (MST) markers have been widely used to identify the source (s) of faecal contamination in water but data are limited on their use for shellfish safety. This study evaluated the source specificity, sensitivity, occurrence and concentration of three viral MST markers i.e. cross-assembly phage (crAssphage), F-specific RNA bacteriophage genogroup II (F-RNA phage GII) and pepper mild mottle virus (PMMoV) using animal faeces (n = 119; 16 animal groups), influent wastewater (n = 12), effluent wastewater (n = 16) and shellfish (n = 33). CrAssphage, F-RNA phage GII and PMMoV had source specific values of 0.97, 0.99 and 0.91, respectively. The sensitivity of MST markers was confirmed by their 100% detection frequency in influent wastewaters. The frequency of detection in effluent wastewater ranged from 81.3% (F-RNA phage GII) to 100% (PMMoV). Concentration of F-RNA phage GII was one log10 (influent wastewater) and 2-3 log10 (effluent wastewater) lower than crAssphage and PMMoV, respectively. Despite lower prevalence of F-RNA phage GII in oysters and mussels compared to crAssphage and PMMoV, concentrations of the three MST markers were similar in mussels. As an indicator of norovirus contamination in shellfish, crAssphage and PMMoV had greater predictive sensitivity (100%; [95% CI; 81.5%-100%)]) and F-RNA phage GII had greater predictive specificity (93.3%; [95% CI; 68.1%-99.8%]). In contrast, crAssphage and F-RNA phage GII have similar accuracy for predicting norovirus in shellfish, however, PMMoV significantly overestimated its presence. Therefore, a combination of crAssphage and F-RNA phage GII analysis of shellfish could provide a robust estimation of the presence of human faecal and norovirus contamination.
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Affiliation(s)
- Pradip Gyawali
- Institute of Environmental Science and Research Ltd (ESR), Porirua 5240, New Zealand.
| | - Megan Devane
- Institute of Environmental Science and Research Ltd (ESR), Christchurch 8041, New Zealand
| | - Paula Scholes
- Institute of Environmental Science and Research Ltd (ESR), Christchurch 8041, New Zealand
| | - Joanne Hewitt
- Institute of Environmental Science and Research Ltd (ESR), Porirua 5240, New Zealand.
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5
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Lee S, Tasaki S, Hata A, Yamashita N, Tanaka H. Evaluation of virus reduction at a large-scale wastewater reclamation plant by detection of indigenous F-specific RNA bacteriophage genotypes. Environ Technol 2019; 40:2527-2537. [PMID: 29471753 DOI: 10.1080/09593330.2018.1444675] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 02/21/2018] [Indexed: 06/08/2023]
Abstract
Evaluating the reduction of virus load in water reclamation plants is important to ensuring the hygienic safety of the reclaimed water. A virus-spiking test is usually used to estimate virus reduction but is not practicable at large-scale plants. Thus, we evaluated virus reduction by ultrafiltration (UF) plus ultraviolet (UV) irradiation at a large-scale reclamation plant (1000 m3/d) by quantifying indigenous F-specific RNA bacteriophages (FRNAPHs). To detect the infectious FRNAPH, we used both plaque assay and integrated culture-reverse-transcription polymerase chain reaction combined with the most probable number assay, which can detect infectious FRNAPH genotypes. For comparison, we determined reductions of indigenous FRNAPHs and spiked MS2 at a small-scale pilot plant (10 m3/d) at the same time. Reductions by UF were not significantly different among the bacteriophages at pilot plants. This result suggests that indigenous bacteriophages could be used for evaluating virus reduction by UF at large-scale plants. Indigenous Genotype I (GI) FRNAPH showed the highest UV resistance, followed by GII, GIII, and GIV. The resistance of GI-FRNAPH was equivalent to that of spiked MS2. The reduction of the total infectious FRNAPHs determined by plaque assay was affected by the predominant FRNAPH genotype, presumably because of their different UV resistances. Our results reveal that indigenous GI-FRNAPH can be a good alternative indicator to spiked MS2 in view of virus reduction during water reclamation. The reclaimed water from our large-scale reclamation plant could be used for irrigation because the expected reduction (6.3 log10) of indigenous GI-FRNAPH achieved the Title 22 (>5 log10).
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Affiliation(s)
- Suntae Lee
- a Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University , Otsu , Japan
| | - Shota Tasaki
- a Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University , Otsu , Japan
| | - Akihiko Hata
- a Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University , Otsu , Japan
| | - Naoyuki Yamashita
- a Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University , Otsu , Japan
| | - Hiroaki Tanaka
- a Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University , Otsu , Japan
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6
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Lee S, Suwa M, Shigemura H. Occurrence and reduction of F-specific RNA bacteriophage genotypes as indicators of human norovirus at a wastewater treatment plant. J Water Health 2019; 17:50-62. [PMID: 30758303 DOI: 10.2166/wh.2018.367] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
F-specific RNA bacteriophages (FRNAPHs) have been suggested as good indicators of the presence of human enteric viruses in water treatment facilities. The occurrence and reduction of norovirus (NoV) and FRNAPH genotypes in wastewater treatment plants (WWTPs) have been well studied; however, the relationship between these genotypes in WWTPs has not been fully elucidated. Thus, we aimed to investigate the occurrence and reduction of FRNAPH genotypes in an attempt to identify NoV indicators in a WWTP via a 1-year survey. All FRNAPH and NoV genotypes were detected in WWTP influents at high rates (71-100%), including the infectious FRNAPH genotype IV (GIV), which has been rarely detected in previous studies. The reductions of FRNAPH GII and NoV GII during wastewater treatment indicated a relationship between the two (r = 0.69, P < 0.01), and the mean values were not significantly different. These results suggested that FRNAPH GII could be used as an appropriate indicator of NoV GII during wastewater treatment. FRNAPH GI was also found to be an appropriate indicator of viral reduction because of its high resistance to wastewater treatment compared with the other FRNAPH and NoV genotypes; therefore, it can be considered as a worst-case scenario organism.
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Affiliation(s)
- Suntae Lee
- Innovative Materials and Resources Research Center, Public Works Research Institute, 1-6 Minamihara, Tsukuba, Ibaraki 305-8516, Japan E-mail:
| | - Mamoru Suwa
- Innovative Materials and Resources Research Center, Public Works Research Institute, 1-6 Minamihara, Tsukuba, Ibaraki 305-8516, Japan E-mail:
| | - Hiroyuki Shigemura
- Innovative Materials and Resources Research Center, Public Works Research Institute, 1-6 Minamihara, Tsukuba, Ibaraki 305-8516, Japan E-mail:
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7
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Abstract
Der Phage fd ist ein flexibles Stäbchen mit einer Sedimentationskonstante von 40 s. Aus elektronenmikroskopischen Aufnahmen ergibt sich für die Länge des Stäbchens 7600 A, für den Durchmesser 50 Å-Einheiten. Der aus der Massenbelegung (1430 Mol.-Gew./A) berechnete Durchmesser beträgt 46 Å-Einheiten. Das Mol.-Gew. des Phagen dürfte 11,3 · 106 ± 10% betragen.
Die einzelsträngige fd-DNS scheint die physikalische Form eines geschlossenen Rings zu haben, ähnlich wie die einzelsträngige DNS des Phagen ΦΧ 174. Dem Sedimentationsverhalten nach hat fd-DNS die gleiche Größe wie ΦΧ-DNS (Mol.-Gew. 1,6·106).
Der sphärische RNS-Phage fr ist ähnlich groß wie die andern bekannten RNS-Phagen. S20
0 ist 79 s. Der elektronenmikroskopische Durchmesser hat einen Wert von 210 Å-Einheiten. Das Mol.-Gew. beträgt etwa 4,1 · 106. 1 g Phage bindet 1,2 g Hydratationswasser.
Sw
0· von fr-RNS in 0,02-m. Citrat bei 20 °C ist 21 s. Bestimmungen in 0.1-m. NaCl geben wesentlich höhere Sedimentationsgeschwindigkeiten, wahrscheinlich weil die Knäuelung der RNS-Moleküle unter den veränderten Bedingungen zunimmt. Die Größe der Änderung ist bemerkenswert, weil die UV-Absorption der fr-RNS in dem Bereich 0,01 — 0,1-m. NaCl praktisch konstant ist (vgl. Teil 1). Das Mol.-Gew. der fr-RNS aus der Sedimentation und der Viskosität beträgt 1,3·106.
Das Sedimentationsverhalten der leichten fd-Teilchen und der leichten fr-Teilchen wird beschrieben.
Der Anhang gibt eine vereinfachte Methode zur Bestimmung des Mol.-Gew. kleiner, sphärischer Viren aus der Sedimentationsgeschwindigkeit und dem durch chemische Analyse ermittelten Nucleinsäuregehalt der Teilchen.
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8
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Pelleïeux S, Bertrand I, Skali-Lami S, Mathieu L, Francius G, Gantzer C. Accumulation of MS2, GA, and Qβ phages on high density polyethylene (HDPE) and drinking water biofilms under flow/non-flow conditions. Water Res 2012; 46:6574-6584. [PMID: 22955017 DOI: 10.1016/j.watres.2012.07.041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 07/17/2012] [Accepted: 07/23/2012] [Indexed: 05/27/2023]
Abstract
Accumulation of enteric viruses on surfaces within a drinking water distribution system was investigated in a reactor using three F-specific RNA bacteriophages (MS2, GA, and Qβ) as models of human pathogenic viruses. The influence of hydrodynamic versus hydrostatic conditions and the effect of the colonization of HDPE surfaces with two-month-old biofilms were assessed for virus accumulation on surfaces. In order to work under controlled laminar conditions and to study various wall shear stresses at the same time, a new rotating disc reactor was designed. Among the wall shear rates applied in the reactor (450 to 1640 s(-1)) no significant differences were observed concerning both the total number of bacteria, which was found to be around 1.7 × 10(7) cells/cm(2) and the virus concentrations on surfaces were about 3 × 10(4), 5 × 10(5) and 3 × 10(5) eq PFU/cm(2) for MS2, GA and Qβ phages, respectively. Comparison between static versus dynamic conditions revealed that both Brownian diffusion and convective diffusion were involved in the transport of these soft colloidal particles and an increase reaching about 1 log in virus concentrations measured on surfaces appeared when hydrodynamic conditions where applied. Our results also showed the influence of the colonization by two-month-old drinking water biofilms which led to a change in the level of virus adhesion. The implication of the physico-chemical properties was also underlined since different adhesion profiles were obtained for the three bacteriophages and MS2 phage was found to be the less adherent one whatever the conditions applied.
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Affiliation(s)
- Sandra Pelleïeux
- Laboratoire de Chimie Physique et Microbiologie pour l'Environnement (LCPME), UMR 7564 CNRS-Université de Lorraine, Nancy, France
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9
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Pierrel J. An RNA Phage Lab: MS2 in Walter Fiers' laboratory of molecular biology in Ghent, from genetic code to gene and genome, 1963-1976. J Hist Biol 2012; 45:109-138. [PMID: 21190066 DOI: 10.1007/s10739-010-9267-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The importance of viruses as model organisms is well-established in molecular biology and Max Delbrück's phage group set standards in the DNA phage field. In this paper, I argue that RNA phages, discovered in the 1960s, were also instrumental in the making of molecular biology. As part of experimental systems, RNA phages stood for messenger RNA (mRNA), genes and genome. RNA was thought to mediate information transfers between DNA and proteins. Furthermore, RNA was more manageable at the bench than DNA due to the availability of specific RNases, enzymes used as chemical tools to analyse RNA. Finally, RNA phages provided scientists with a pure source of mRNA to investigate the genetic code, genes and even a genome sequence. This paper focuses on Walter Fiers' laboratory at Ghent University (Belgium) and their work on the RNA phage MS2. When setting up his Laboratory of Molecular Biology, Fiers planned a comprehensive study of the virus with a strong emphasis on the issue of structure. In his lab, RNA sequencing, now a little-known technique, evolved gradually from a means to solve the genetic code, to a tool for completing the first genome sequence. Thus, I follow the research pathway of Fiers and his 'RNA phage lab' with their evolving experimental system from 1960 to the late 1970s. This study illuminates two decisive shifts in post-war biology: the emergence of molecular biology as a discipline in the 1960s in Europe and of genomics in the 1990s.
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Affiliation(s)
- Jérôme Pierrel
- Laboratoire Épistémê (EA 2971), Bordeaux University, 40 rue Lamartine, 33405 Talence, France.
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10
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Gourmelon M, Caprais MP, Le Mennec C, Mieszkin S, Ponthoreau C, Gendronneau M. Application of library-independent microbial source tracking methods for identifying the sources of faecal contamination in coastal areas. Water Sci Technol 2010; 61:1401-9. [PMID: 20351418 DOI: 10.2166/wst.2010.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Faecal contamination sources were identified in coastal areas around the Guerande-Atlantique peninsula using two microbial source tracking (MST) methods: (i) Bacteroidales host-specific 16S rRNA gene markers measured by real-time PCR and (ii) F-specific bacteriophage (FRNAPH) genotyping. Both methods were used on 63 water samples from 7 water courses. HF183 marker and bacteriophage genogroup II (FRNAPH II) were detected in all water samples and in the majority of water samples, respectively, from La Torre stream (W5), Piriac (W2), R2000 (W3) and Mazy (W7) rain water drains, and also detected, less frequently, in Le Nau drain (W4), suggesting contamination by human faecal sources at these sites. These human markers were weakly detected in Pouliguen channel (W6). Furthermore, BacR and bacteriophage genogroup I (FRNAPH I) were also detected, but at lower concentration and frequency. So, site W6 seems to be contaminated by multiple sources, though mainly human. Finally, BacR was detected twice in Pont d'Armes channel (W1), whereas HF183 was not detected. FRNAPH I and II were detected in only 3 out of 12 water samples. Site W1 seems mainly contaminated by animal sources. As a result of our findings, actions were taken to remediate water and shellfish quality.
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Affiliation(s)
- M Gourmelon
- Ifremer, EMP, Laboratoire de Microbiologie, 29280 Plouzané, France.
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11
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Abstract
Populations are at risk of extinction when unsuitable or when sink habitat exceeds a threshold frequency in the environment. Sinks that present cues associated with high-quality habitats, termed ecological traps, have especially detrimental effects on net population growth at metapopulation scales. Ecological traps for viruses arise naturally, or can be engineered, via the expression of viral-binding sites on cells that preclude viral reproduction. We present a model for virus population growth in a heterogeneous host community, parameterized with data from populations of the RNA bacteriophage Phi6 presented with mixtures of suitable host bacteria and either neutral or trap cells. We demonstrate that viruses can sustain high rates of population growth in the presence of neutral non-hosts as long as some host cells are present, whereas trap cells dramatically reduce viral fitness. In addition, we demonstrate that the efficacy of traps for viral elimination is frequency dependent in spatially structured environments such that population viability is a nonlinear function of habitat loss in dispersal-limited virus populations. We conclude that the ecological concepts applied to species conservation in altered landscapes can also contribute to the development of trap cell therapies for infectious human viruses.
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Affiliation(s)
- John J Dennehy
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520, USA
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12
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Cheng Y, Niu J, Zhang Y, Huang J, Li Q. Preparation of His-tagged armored RNA phage particles as a control for real-time reverse transcription-PCR detection of severe acute respiratory syndrome coronavirus. J Clin Microbiol 2006; 44:3557-61. [PMID: 17021082 PMCID: PMC1594775 DOI: 10.1128/jcm.00713-06] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Armored RNA has been increasingly used as both an external and internal positive control in nucleic acid-based assays for RNA virus. In order to facilitate armored RNA purification, a His6 tag was introduced into the loop region of the MS2 coat protein, which allows the exposure of multiple His tags on the surface during armored RNA assembly. The His-tagged armored RNA particles were purified to homogeneity and verified to be free of DNA contamination in a single run of affinity chromatography. A fragment of severe acute respiratory syndrome coronavirus (SARS-CoV) genome targeted for SARS-CoV detection was chosen for an external positive control preparation. A plant-specific gene sequence was chosen for a universal noncompetitive internal positive control preparation. Both controls were purified by Co2+ affinity chromatography and were included in a real-time reverse transcription-PCR assay for SARS-CoV. The noncompetitive internal positive control can be added to clinical samples before RNA extraction and enables the identification of potential inhibitive effects without interfering with target amplification. The external control could be used for the quantification of viral loads in clinical samples.
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Affiliation(s)
- Yangjian Cheng
- Department of Biomedical Sciences, Xiamen University, South Road of Siming 422, Xiamen 361005, China
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13
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Pang L, Close M, Goltz M, Sinton L, Davies H, Hall C, Stanton G. Estimation of septic tank setback distances based on transport of E. coli and F- RNA phages. Environ Int 2004; 29:907-921. [PMID: 14592568 DOI: 10.1016/s0160-4120(03)00054-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Setback distances between septic tank systems and the shorelines of Lake Okareka, New Zealand were determined from model simulations for a worst-case scenario, using the highest hydraulic conductivity and gradient measured in the field, removal rates of the microbial indicators (Escherichia coli and F-RNA phages) determined from a column experiment, and maximum values of the design criteria for the disposal system, and assuming an absence of an unsaturated zone, a continuous discharge of the raw effluent from a failed or non-complying treatment system (both indicators at concentrations of 1x10(7) counts/100 ml) into the groundwater and no sorption of pathogens in the aquifer. Modelling results suggest that the minimal setback distances were 16 m to satisfy the New Zealand Recreational Water Quality Guidelines for E. coli <126 per 100 ml (Ministry for the Environment, 1999) and 48 m to meet the Drinking-Water Standards for New Zealand 2000 for enteric virus <1 per 100 l (Ministry of Health, 2000). These distances may be applicable for other lakeshores in pumice sand aquifers with groundwater velocities <7 m/day. Findings of laboratory column and batch experiments provided an insight into the microbial attenuation and transport processes in pumice sand aquifers. Bacterial removal was predominately through filtration (87-88%) and partially by die-off (12-13%), while viral removal was by both die-off (45%) and filtration (55%). In addition, microbial die-off in groundwater without aquifer material (i.e., free microbes) was much lower than die-off in groundwater with aquifer material (i.e., sorbed microbes) and contributed only 2-6% to the total removal. This implies that the setback distances estimated from die-off rates for the free microbes, determined in the laboratory without considering aquifer media and other removal processes, which are often reported in the literature, could be larger than necessary.
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Affiliation(s)
- Liping Pang
- Institute of Environmental Science and Research Ltd., PO Box 29181, Christchurch, New Zealand.
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14
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Gantzer C, Gillerman L, Kuznetsov M, Oron G. Adsorption and survival of faecal coliforms, somatic coliphages and F-specific RNA phages in soil irrigated with wastewater. Water Sci Technol 2001; 43:117-124. [PMID: 11464739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study was carried out to compare the adsorption and survival of faecal coliforms, somatic coliphages and F-specific RNA phages in soil irrigated with wastewater. Adsorption isotherms showed that 3-10x more faecal coliforms than somatic coliphages were adsorbed from wastewater onto soil. The adsorption behavior of F-specific RNA phages was intermediate between those of these two microorganisms. In wastewater, the inactivation factor of somatic coliphages at 8-22 degrees C was 5-7 lower than those of faecal coliforms. F-specific RNA phages have a decrease close to faecal coliforms. In soil, at temperatures of 8-22 degrees C and at moistures of 15-35%, somatic coliphages survived longer than the two other microorganisms. These results seemed to be confirmed by the soil column experiments. The rate of inactivation of all microorganisms was lower in soil than in wastewater and depended extensively on soil temperature and moisture content. Survival was optimal at low temperature (8 degrees C) and low moisture content (15%). Thus, somatic coliphages seemed to be a better indicator of faecal contamination than faecal coliforms under our experimental conditions and based only on the two criteria tested (survival and adsorption). Somatic coliphages were able to contaminate the soil over greater distances and survive better in both wastewater and soil than faecal coliforms. These results need to be confirmed by studies on several soil columns using different kinds of soil and different kinds of wastewater.
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Affiliation(s)
- C Gantzer
- Laboratoire de Virologie, Faculté de Pharmacie, 5 rue Albert Lebrun, B.P. 403, 54001 Nancy, France.
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WEISSMANN C, SIMON L, OCHOA S. Induction by an RNA phage of an enzyme catalyzing incorporation of ribonucleotides into ribonucleic acid. Proc Natl Acad Sci U S A 1998; 49:407-14. [PMID: 13999778 PMCID: PMC299844 DOI: 10.1073/pnas.49.3.407] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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OKAMOTO K, SUGINO Y, NOMURA M. Synthesis and turnover of phage messenger RNA in E. coli infected with bacteriophage T4 in the presence of chloromycetin. J Mol Biol 1998; 5:527-34. [PMID: 13939775 DOI: 10.1016/s0022-2836(62)80126-0] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Nooren IM, Wang KY, Borer PN, Pelczer I. Full 1H NMR assignment of a 24-nucleotide RNA hairpin: application of the 1H 3D-NOE/2QC experiment. J Biomol NMR 1998; 11:319-328. [PMID: 9691279 DOI: 10.1023/a:1008252510576] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The subject RNA models the binding site for the coat protein of the R17 virus, as well as the ribosome recognition sequence for the R17 replicase gene. With an RNA of this size, overlaps among the sugar protons complicate assignments of the 1H NMR spectrum. The cross peaks that overlap significantly in 2D-NOE spectra can frequently be resolved by introducing a third, in our approach the double-quantum, frequency axis. In particular the planes in a 3D-NOE/2QC spectrum perpendicular to the 2Q axis are extremely useful, showing a highly informative repeating NOE-2Q pattern. In this experiment substantial J-coupling confers special advantages. This always occurs for geminal pairs (H5'/H5" for RNA plus H2'/H2" for DNA), as well as for H5/H6, for H3'/H4' in sugars with substantial populations of the N-pucker, for H1'/H2' for S-puckered sugars, and usually for H2'/H3'. For the 24-mer RNA hairpin the additional information from the 3D-NOE/2QC spectrum allowed assignment of all of the non-exchangeable protons, eliminating the need for stable-isotope labeling.
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Affiliation(s)
- I M Nooren
- Chemistry Department, Syracuse University, NY 13244-4100, USA
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SEKIGUCHI M, COHEN SS. THE SYNTHESIS OF MESSENGER RNA WITHOUT PROTEIN SYNTHESIS. II. SYNTHESIS OF PHAGE-INDUCED RNA AND SEQUENTIAL ENZYME PRODUCTION. J Mol Biol 1996; 8:638-59. [PMID: 14187391 DOI: 10.1016/s0022-2836(64)80114-5] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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WEISSMANN C, BORST P, BURDON RH, BILLETER MA, OCHOA S. REPLICATION OF VIRAL RNA, III. DOUBLE-STRANDED REPLICATIVE FORM OF MSW PHAGE RNA. Proc Natl Acad Sci U S A 1996; 51:682-90. [PMID: 14166775 PMCID: PMC300140 DOI: 10.1073/pnas.51.4.682] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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WEISSMANN C, BORST P, BURDON RH, BILLETER MA, OCHOA S. REPLICATION OF VIRAL RNA. IV. PROPERTIES OF RNA SYNTHETASE AND ENZYMATIC SYNTHESIS OF MS2 PHAGE RNA. Proc Natl Acad Sci U S A 1996; 51:890-7. [PMID: 14173008 PMCID: PMC300179 DOI: 10.1073/pnas.51.5.890] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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Abstract
Previous work has identified three intergenic regions from the early region of actinophage øC31 where transcription was either terminated or the mRNA was processed. Here we show using in vivo and in vitro approaches that these regions contain rho-independent terminators designated eta, etb and etc. Transcripts through eta-c would be expected to form stable RNA stem-loops but would lack poly-U tails. Eta-c contained part or all of the conserved sequences 5' AGCCCC and 5' GGGGCTT. A Streptomyces 'terminator probe' vector, pUGT1, was constructed and used to assay the efficiency of termination of transcription by eta-c from the thiostrepton-inducible tipA promoter by measuring the expression of a downstream reporter gene (aphII). In pUGT1 etb was at best a minor terminator in vivo whilst eta and etc exhibited strong termination activity. In vitro termination was assayed using templates containing a synthetic promoter recognised by E.coli RNA polymerase and fragments containing eta-c inserted downstream. All three terminators stimulated the formation of 3' ends in the promoter-distal arm of the inverted repeats with efficiencies eta > etc > etb. As all three terminators either overlap with or lie close to sequences which interact with phage repressor proteins (conserved inverted repeats, CIRs) and these can potentially form stem-loop structures in RNA, the effect of CIRs on termination was also investigated. Termination at etb was unaffected by the presence or absence on the transcription template of CIR3. CIR4 forms the central 17 bp of etc and a 37 nt deletion which eliminated this stem-loop abolished termination in vivo and in vitro. Eta was investigated using an antisense oligonucleotide interference assay; an oligo designed to bind the 5' arm of eta inhibited termination whilst an oligo antisense to CIR5 was ineffective and an oligo targeted further upstream enhanced termination. Taken together these data show that eta-c are intrinsic, rho-independent terminators of varying efficiencies despite the absence of a poly-U tail.
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Affiliation(s)
- C J Ingham
- Robertson Laboratory of Biotechnology, University of Glasgow, UK
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Abstract
Recent progress on the molecular mechanism of RNA phage morphogenesis is described. Functional studies, both in vivo and in vitro, are correlated with the latest structural studies on phages, their capsids and the assembly initiation RNA stem-loop.
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Affiliation(s)
- P G Stockley
- Department of Genetics, University of Leeds, England
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Whelan KF, Maher D, Colleran E, Taylor DE. Genetic and nucleotide sequence analysis of the gene htdA, which regulates conjugal transfer of IncHI plasmids. J Bacteriol 1994; 176:2242-51. [PMID: 7908903 PMCID: PMC205345 DOI: 10.1128/jb.176.8.2242-2251.1994] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
IncHI plasmids are naturally repressed for conjugative transfer and do not allow efficient propagation of the IncH pilus-specific phage Hgal. Transposons Tn7, Tn5, and TnlacZ were inserted into IncHI plasmids R478, R477-1, and R27, respectively, leading to the isolation of several plasmid mutants which exhibited increased levels of transfer and also permitted good lysis with phage Hgal. A 4.3-kb HindIII fragment from R478 reversed both phenotypic effects of derepression for the R477-1::Tn5 and the R478::Tn7 derivatives, pKFW99 and pKFW100, respectively. Exonuclease III deletions of this fragment and nucleotide sequence analysis indicated that the gene responsible for transfer repression, named here htdA, encoded a polypeptide of 150 amino acids. Cloning and sequence analysis of pDT2454 (R27::TnlacZ) revealed that the transposon had inserted into an open reading frame (ORF) which had an 83% amino acid identity with the R478 htdA gene. Maxicell analysis showed both the R27 and R478 HtdA products had molecular masses of 19.9 kDa. Conjugation experiments showed that the cloned htdA determinants caused a significant reduction of the transfer frequencies of wild-type R478 and R27 plasmids. Examination of both R478 derepressed mutants, pKFW100 and pKFW101, indicated that both transposon insertions occurred upstream of the htdA ORF. The results suggest that HtdA is a regulatory component of IncH plasmid transfer and also show that the region upstream of the htdA ORF is involved in transfer repression. The locations of the htdA determinants were identified on the plasmid maps of R27 and R478.
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Affiliation(s)
- K F Whelan
- Department of Medical Microbiology and Infectious Diseases, University of Alberta, Edmonton, Canada
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Kumar R, Wieben E, Beecher SJ. The molecular cloning of the complementary deoxyribonucleic acid for bovine vitamin D-dependent calcium-binding protein: structure of the full-length protein and evidence for homologies with other calcium-binding proteins of the troponin-C superfamily of proteins. Mol Endocrinol 1989; 3:427-32. [PMID: 2710141 DOI: 10.1210/mend-3-2-427] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
We have cloned the cDNA for bovine intestinal vitamin D-dependent calcium-binding protein and, based on the sequence of the DNA, have deduced the structure of the full-length protein. The sequence of the cDNA clone predicts a protein comprised of 78 amino acids with a mol wt of 8788. The mRNA for the protein in bovine duodenum is about 500-600 bases in length. The protein sequence of bovine intestinal calcium-binding protein is 87% homologous with the sequence of porcine intestinal vitamin D-dependent calcium-binding protein and 81% homologous with the sequence of rat intestinal vitamin D-dependent calcium-binding protein. Hydrophilicity plots of the proteins noted above show that despite differences in amino acid sequence the proteins have similar patterns. In addition, the predicted secondary structure of the proteins is similar. Bovine intestinal calcium-binding protein shows 48.6% homology with the alpha-chain and 38.2% homology with the beta-chain of bovine S-100 protein and a similar high degree of homology with the beta-chain of human S-100 protein. The protein also demonstrates 36-43% homology with parvalbumin alpha and beta from various species and with troponin-C. There is some homology with the 28K vitamin D-dependent calcium-binding proteins. Vitamin D-dependent bovine intestinal calcium-binding protein is closely related to other mammalian intestinal calcium-binding proteins and to the S-100 proteins, parvalbumins, and troponin-C.
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Affiliation(s)
- R Kumar
- Department of Medicine, Mayo Clinic, Rochester, Minnesota 55905
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Suganuma N, Seo H, Narita O, Tomoda Y, Matsui N. Measurement of human prolactin messenger RNA in decidual tissues using complementary DNA probe cloned in M13mp9 bacteriophage. Nihon Sanka Fujinka Gakkai Zasshi 1986; 38:253-60. [PMID: 3007638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A human prolactin (PRL) cDNA clone was digested with restriction enzyme Pst I and the resultant fragments were cloned into bacteriophage M13mp9. Single stranded recombinant DNAs having a coding strand of the PRL cDNA were selected by hybridization with 125I-labeled PRL mRNA obtained from human prolactinoma tissue. One of the single stranded recombinant DNAs was purified by agarose gel electrophoresis and labeled with 125I to a specific activity of 1.4 X 10(8) cpm per microgram of DNA. The probe could be successfully used in RNA dot hybridization. Analysis of poly (A) RNAs from prolactinoma, liver and placental tissues revealed that this probe was specific to PRL mRNA sequence. Hybridization of poly (A) RNA from decidual tissue to this probe revealed the presence of PRL mRNA sequence. However, PRL mRNA in decidua was at least 20,000 times less than that in pituitary prolactinoma.
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Abstract
Bacteriophage P1 transduction was used to study the incompatibility group H1 plasmid pRG1251, molecular weight 120 x 10(6), and the incompatibility group H2 plasmid pSD114, molecular weight 166 x 10(6). The order of resistance (R) determinants on pSD114 was deduced from transduction and segregation experiments to be chloramphenicol-tetracycline-kanamycin-streptomycin. Resistance to tellurium and to coliphages, which are properties also encoded by many H2 plasmids, were not transduced with the other markers. On pRG1251, the ampicillin and tetracycline resistance markers appear to be located together, as do the chloramphenicol, streptomycin, and sulfamethoxazole resistance markers. Frequently, blocks of R determinants were transposed to the P1 genome or to the Escherichia coli chromosome. P1 DNA was isolated which carried the chloramphenicol, streptomycin, and sulfamethoxazole markers from pRG1251 and had a molecular weight of 64 x 10(6). Other P1 prophages carried R determinants from pSD114 and had molecular weights of 86 x 10(6). A plasmid of molecular weight 124 x 10(6) was also isolated which contained incompatibility determinants from P1 (incompatibility group Y) and from the H2 group plasmid. The mechanism of formation of these unusual plasmid species is discussed.
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van Styvendaele BJ. The making of an RNA phage bibliography with personal information retrieval by microcomputer. Methods Inf Med 1979; 18:158-64. [PMID: 392223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Abstract
Cell-free filtrates of F(+) strains of Escherichia coli "inactivate" RNA phages. The active agents have been identified in the electron microscope as thin appendages called F-pili. Complexes of F-pili and phage may be easily assayed because of their retention by membrane filter pads. Calcium ion is required for formation of the complex.
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TIKHONENKO AS, BESPALOVA I, KRIVISKII AS. [ELECTRON-MICROSCOPIC STUDIES ON THE RNA-CONTAINING MS2 PHAGE AND ITS DEVELOPMENT IN THE BACTERIAL CELL]. Dokl Akad Nauk SSSR 1965; 160:704-6. [PMID: 14277316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
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KAERNER HC, HOFFMANN-BERLING H. [THE FORMATION OF DOUBLE-STRANDED RNA FOR PROPAGATION OF A BACTERIOPHAGE CONTAINING RNA]. Z Naturforsch B 1964; 19:593-604. [PMID: 14258805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
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Abstract
A class of host-dependent mutants of RNA-phage f2 are dependent on streptomycin for growth in certain bacterial hosts. Maximum response to streptomycin occurred late in the growth cycle of phage, indicating phenotypic "repair" of a late phage function.
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HUPPERT J. [BACTERIOPHAGES CONTAINING RNA]. Pathol Biol 1963; 11:1407-12. [PMID: 14115985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
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Abstract
Part of the RNA synthesized from nucleoside triphosphate precursors by partially purified RNA synthetase, an enzyme induced in Escherichia coli by the RNA-containing phage MS 2, is resistant to hydrolysis by ribonuclease. Upon heating in 0.15M sodium chloride, 0.015M sodium citrate followed by fast cooling the material becomes ribonuclease-sensitive with a sharp transition at 102 degrees to 104 degrees C. The suggestion that the ribonuclease-resistant product is double-stranded RNA is reinforced by restoration of the ribonuclease resistance of the heat-denatured material by reannealing at temperatures just below the transition point and by its buoyant density in cesium sulfate. It is suggested that double-stranded RNA is the replicative form of MS 2 phage RNA.
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HOFFMANN-BERLING H, MARVIN DA, DUERWALD H. [A FILAMENTOUS DNA PHAGE (FD) AND A SPHERICAL RNA PHAGE (FR), HOST-SPECIFIC FOR THE MALE STRAIN OF E. COLI. 1. PREPARATION AND CHEMICAL PROPERTIES OF FD AND FR]. Z Naturforsch B 1963; 18:876-83. [PMID: 14104677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
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HOFFMANN-BERLING H, DUERWALD H, BEULKE I. [A FILAMENTOUS DNA PHAGE (FD) AND A SPHERICAL RNA PHAGE (FR), HOST-SPECIFIC FOR THE MALE STRAIN OF E. COLI. III. BIOLOGICAL BEHAVIOR OF FD AND FR]. Z Naturforsch B 1963; 18:893-8. [PMID: 14101862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
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