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PubMed1979

Expansion of the host range of coliphage P1 and gene transfer from enteric bacteria to other gram-negative bacteria.

The bacterial host range of coliphage P1 was extented by using the heat-inducible phage P1clr100KM. A gene for kanamycin resistance was transferred from Escherichia coli to members of the family Enterobacteriaceae and some other genera of gram-negative bacteria. P1 phage was produced by thermal induction from the lysogens of all these kanamycin-resistant bacteria except some strains.

Bacteria↗
PubMed1981

Distribution of ribonucleic acid coliphages in animals.

To determine the distribution pattern of ribonucleic acid (RNA) coliphages (classified by serological groups I through IV) in animal sources, we isolated RNA phages from (i) feces samples from domestic animals (cows, pigs, horses, and fowls), some other animals in a zoological garden, and humans, (ii) the gastrointestinal contents of cows and pigs, and (iii) sewage samples from treatment plants in slaughter houses. These samples were then analyzed serologically. The concentration of RNA phages in the first and second kinds of material was fairly low (10 to 10(3) plaque-forming units per original phage sample), whereas that in the third kind of material was fairly high (10(3) to 10(5) plaque-forming units per original phage sample). Concerning the group types of the RNA phages in the first and second kinds of material, human feces contained RNA phages of groups II and III almost equally, the gastrointestinal contents of pigs included those of groups I and II equally, and the feces or gastrointestinal contents of other mammals other than humans and pigs had those of group I exclusively. In the third type of material we found mostly group I phages with a minor fraction of group II phages. Thus, the prominent features of the distribution pattern of RNA phages are the predominance of groups III and II in humans and the predominance of group I in animals.

Animals↗
PubMed1981

Distribution of ribonucleic acid coliphages in Korea.

To determine the geographical distribution of ribonucleic acid (RNA) coliphages in Korea, we collected sewage samples from domestic drainage in densely populated urban areas in July through August, 1979. Of 132 samples, 74 (56%) contained RNA phages (106 strains). They were classified into groups I, II and III (4:47:55) by serological analysis. Based on previous data for Japan (groups II and III [3:11]) and Southeast Asia (mostly group III), the distribution pattern of RNA phages in Korea was of an intermediate type between those of Japan and Southeast Asia.

Coliphages↗
PubMed1981

Distribution of ribonucleic acid coliphages in raw sewage from treatment plants in Japan.

To determine the transmission cycle of ribonucleic acid (RNA) coliphages in their natural habitats, we investigated the distribution patterns of RNA phages in raw sewage collected from treatment plants in various localities in Japan. Most of the sewage samples contained group II and III phages. Samples from treatment plants in Sapporo, Tokyo, and Toyama contained appreciable amounts of group I phages in addition to the group II and III phages. As a whole, raw sewage from treatment plants in Japan contained RNA phages of the three groups in the ratio 1:2:5, group I/II/III. Based on the distribution patterns of RNA phages in sewage from domestic drainage in Japan proper (group II/III, 3:1), in animal feces and sewage from slaughter houses (mostly group I), and in human feces (group II/III, 1:1), it can be reasonably said that group I phages tend to be introduced from animal sources and group II and III phages tend to be introduced from human sources. Raw sewage from treatment plants in Japan consists mainly of human feces, sewage from domestic drainage, and industrial wastewater, and, in part, from slaughter houses. In fact, sewage from slaughter houses together with that from human sources flowed into the treatment plants of Tokyo as far as we could confirm.

Coliphages↗
PubMed1986

Practical direct plaque assay for coliphages in 100-ml samples of drinking water.

A practical single-agar-layer plaque assay for the direct detection of coliphages in 100-ml samples of water was designed and evaluated. With this assay a 100-ml sample of water, an agar medium containing divalent cations, and the host Escherichia coli C (ATCC 13706) were mixed in a single container, and the mixture was plated on 10 14-cm-diameter petri dishes. It was more sensitive, reliable, and accurate than various other methods and proved rapid, simple, and economic.

Agar↗
PubMed1995

In situ inactivation of animal viruses and a coliphage in nonaerated liquid and semiliquid animal wastes.

The persistence of five animal viruses, representing picorna-, rota-, parvo-, adeno-, and herpesviruses, and the coliphage f2 was determined in the field by exposing the viruses to different animal wastes and by adopting an established filter sandwich technique. This technique allows us to copy the natural state of viruses in the environment, where adsorption onto or incorporation into suspended solids may prolong virus survival. Using filter sandwiches either equipped with porous (15 nm in diameter) or poreless polycarbonate (PC) membranes, it was possible to differentiate between overall virus inactivation and the effect of virucidal agents that act through poreless PC membranes. Depending on ambient temperature, pH, and type of animal waste, values for time, in days, required for a 90% reduction of virus titer varied widely, ranging from less than 1 week for herpesvirus to more than 6 months for rotavirus. Virus inactivation progressed substantially faster in liquid cattle manure, a mixture of urine and water (pH > 8.0), than in semiliquid wastes that consisted of mixtures of feces, urine, water, and bedding materials (pH < 8.0). Hitherto unidentified virucidal agents that permeate poreless PC membranes contributed substantially to the overall inactivation. On the other hand, substances that protect rotavirus and possibly other viruses from inactivation may be present in animal wastes. Together, the study showed that viruses contained in manure may persist for prolonged periods of time if stored under nonaerated conditions. At times of land application, this may lead to environmental contamination with pathogens.

Adenoviridae↗
PubMed2003

Morphological, host range, and genetic characterization of two coliphages.

Two coliphages, AR1 and LG1, were characterized based on their morphological, host range, and genetic properties. Transmission electron microscopy showed that both phages belonged to the Myoviridae; phage particles of LG1 were smaller than those of AR1 and had an isometric head 68 nm in diameter and a complex contractile tail 111 nm in length. Transmission electron micrographs of AR1 showed phage particles consisting of an elongated isometric head of 103 by 74 nm and a complex contractile tail 116 nm in length. Both phages were extensively tested on many strains of Escherichia coli and other enterobacteria. The results showed that both phages could infect many serotypes of E. coli. Among the enterobacteria, Proteus mirabilis, Shigella dysenteriae, and two Salmonella strains were lysed by the phages. The genetic material of AR1 and LG1 was characterized. Phage LG1 had a genome size of 49.5 kb compared to 150 kb for AR1. Restriction endonuclease analysis showed that several restriction enzymes could degrade DNA from both phages. The morphological, genome size, and restriction endonuclease similarities between AR1 and phage T4 were striking. Southern hybridizations showed that AR1 and T4 are genetically related. The wide host ranges of phages AR1 and LG1 suggest that they may be useful as biocontrol, therapeutic, or diagnostic agents to control and detect the prevalence of E. coli in animals and food.

Bacteria↗
PubMed2004

Characterization of coliphage PR772 and evaluation of its use for virus filter performance testing.

Virus filtration is a key clearance unit operation in the manufacture of recombinant protein, monoclonal antibody, and plasma-derived biopharmaceuticals. Recently, a consensus has developed among filter manufacturers and end users about the desirability of a common nomenclature and a standardized test for classifying and identifying virus-retentive filters. The Parenteral Drug Association virus filter task force has chosen PR772 as the model bacteriophage to standardize nomenclature for large-pore-size virus-retentive filters (filters designed to retain viruses larger than 50 to 60 nm in size). Previously, the coliphage PR772 (Tectiviridae family) has been used in some filtration studies as a surrogate for mammalian viruses of around 50 to 60 nm. In this report, we describe specific properties of PR772 critical to the support of its use for the standardization of virus filters. The complete genomic sequence of virulent phage PR772 was determined. Its genome contains 14,946 bp with an overall G+C content of 48.3 mol%, and 32 open reading frames of at least 40 codons. Comparison of the PR772 nucleotide sequence with the genome of Tectiviridae family prototype phage PRD1 revealed 97.2% identity at the DNA level. By dynamic light-scattering analysis, its hydrodynamic diameter was measured as 82 +/- 6 nm, consistent with use in testing large-virus-retentive filters. Finally, dynamic light-scattering analysis of PR772 preparations purified on CsCl gradients showed that the phage preparations are largely monodispersed. In summary, PR772 appears to be an appropriate model bacteriophage for standardization of nomenclature for larger-pore-size virus-retentive filters.

Biotechnology↗
PubMed1967

Evaluation of T3 coliphage injuries and efficacy of selected materials in preventing them.

A procedure was developed to analyze the inactivation of coliphage T3 during freeze-drying and subsequent rehydration. The amount of gross disruption of the phage as compared with the amount of phage remaining intact was evaluated by cesium chloride density gradient centrifugation. The amount of phage material able to adsorb to host cells and the residual infectivity after the drying were also evaluated. These analyses made it possible to determine the amount of phage material (i) degraded to protein and nucleic acid, (ii) intact or largely intact, (iii) capable of adsorption on host cells, and (iv) infective. The capacities of casein hydrolysate, ascorbic acid, thiourea, bovine albumin, polyethyleneglycol, raffinose, inositol, and lipoproteins to protect T3 bacteriophage from the stress of freeze-drying were investigated.

Albumins↗
PubMed1968

Infectivity-destroying effect of humidity for dried coliphage T1.

Infectivity of dried coliphage T1 has been measured as a function of humidity, temperature, and atmospheric pressure. Loss of infectivity by a factor of 10(4) was caused by water vapor of approximately 40 to 85% saturation when the microorganisms were kept for 3 days at 34 C in evacuated containers. At humidities below 40% and above 90% saturation, no loss of infectivity occurred. At a temperature of 24 C, the infectivity loss was 20-fold. When the virus preparation was kept at 34 C and atmospheric pressure, some loss of infectivity was also found at humidities below 40% and above 90% saturation. Damage to tail proteins or to the phage chromosome is considered as a possible explanation for the inactivation.

Coliphages↗
PubMed1969

Enhanced recovery of airborne T3 coliphage and Pasteurella pestis bacteriophage by means of a presampling humidification technique.

This paper reports a series of experiments in which two methods of collecting airborne bacteriophage particles were compared. A standard aerosol sampler, the AGI-30, was evaluated for its competence in measuring the content of bacteriophage aerosols. It was used alone or with a prewetting or humidification device (humidifier bulb) to recover T(3) coliphage and Pasteurella pestis bacteriophage particles from aerosols maintained at 21 C and varied relative humidity. Collection of bacteriophage particles via the humidifier bulb altered both the initial recovery level and the apparent biological decay. Sampling airborne bacteriophage particles by the AGI-30 alone yielded data that apparently underestimated the maximal number of potentially viable particles within the aerosol, sometimes by as much as 3 logs.

Aerosols↗
PubMed1970

Distribution of coliphages in Hong Kong sewage.

Coliphage content of sewage collected from 11 different localities in Hong Kong was determined. The number of plaque-forming units (PFU) ranged from 0.036 x 10(3) to 15.9 x 10(3) per ml. In general, urban sewage tended to be richer than rural sewage both in PFU count as well as plaque morphological variation. Seventy-seven isolates were subjected to a host range study. Fifty per cent of these were able to grow on Escherichia coli K-12 as well as E. coli B. Approximately 32% were found to be male specific, and the remaining 18% were K-12 specific although sex-indifferent.

Agar↗
PubMed1971

Accumulation and elimination of coliphage S-13 by the hard clam, Mercenaria mercenaria.

Accumulation and elimination of viral particles by hard clams, Mercenaria mercenaria, were studied with the coliphage S-13 as a working model. Escherichia coli uptake and elimination were simultaneously monitored. Clams were exposed to low levels of S-13 (7 particles/ml) in running seawater for several days, achieving titers in tissues from 2 to more than 1,000 times the levels to which they had been exposed. Bacterial accumulation (previously established by other workers) was comparable. Upon exposure to virus-free running water, clams polluted to relatively low levels (100 plaque-forming units/ml) eliminated most of their bacterial contaminants in 24 to 48 hr. Viral contaminants, however, persisted for several days to weeks even under ideal conditions for clam activity, provided that the temperature remained below the inactivation threshold for the virus. Most of the accumulated virus appeared to be sequestered in the digestive gland. These sequestered particles are refractory to those mechanisms responsible for elimination of bacterial contaminants. This discrepancy points out the need for caution in evaluating the efficiency of shellfish depuration processes, especially if only a bacterial criterion is used as a monitoring system.

Coliphages↗
PubMed1972

Integration stie of noninducible coliphage 186.

From conjugational data, the attachment site for noninducible coliphage 186 (att186) was located between the origins of Hfr strains KL16 and KL98, and close to the pheA gene in Escherichia coli K-12. P1 transductions indicated that att186 lies at 51 min on the standard genetic map of E. coli, with the order cysC-nalB-att186-pheA. The presence of prophage 186 in the donor destroyed linkage between nalB and pheA, which is taken as evidence for the integration of the 186 prophage between these genes.

Chromosome Mapping↗
PubMed1975

Genes affecting coliphage BF23 and E colicin sensitivity in Salmonella typhimurium.

Rough strains of Salmonella typhimurium were sensitive to coliphage BF23. Spontaneous mutants resistant to BF23 (bfe) were isolated, and the trait was mapped using phage P1. The bfe gene in S. typhimurium was located between argF (66% co-transducible) and rif (61% co-transducible). The BF23-sensitive S. typhimurium strains were not sensitive to the E colicins. Cells of these rough strains absorbed colicin, as measured by loss of E2 or E3 killing units from colicin solutions and by specific adsorption of 125I-colicin E2 to bfe+ cells. Sensitivity to colicins E1, E2, and E3 was observed in a S. typhimurium strain carrying the F'8 gal+ episome. This episome complemented the tolB mutation of Escherichia coli. We conclude that the bfe+ protein satisfies requirements for adsorption of both phage BF23 and the E colicins. In addition, expression of a gene from E. coli, possibly tolB, is necessary for efficient E colicin killing of S. typhimurium.

Adsorption↗
PubMed1976

Fractionation of membrane vesicles from coliphage M13-infected Escherichia coli.

Membrane vesicles were prepared by osmotic lysis of spheroplasts from M13-infected Escherichia coli. Reduced nicotinamide adenine dinucleotide (NADH) oxidase (reduced NAD: oxidoreductase, EC 1.6.99.3) and Mg2+-Ca2+-activated adenosine triphosphatase (ATP phosphohydrolase, EC 3.6.1.3), which are normally localized to the inner surface of the cytoplasmic membrane, were 50% acceesible to their polar substrates in these vesicles. The major coat protein of coliphage M13 is also bound to the cytoplasmic membrane (prior to phage assembly) but with its antigenic sites exposed to the exterior of the cell. Antibody to M13 coat protein was used to fractionate membrane vesicles. Neither agglutinated nor unagglutinated vesicles had altered NADH oxidase and adenosine triphosphatase specific activities. This is inconsistent with such vesicles being a mixture of correctly oriented and completely inverted membrane sacs and suggests that NADH oxidase, adenosine triphosphatase, M13 coat protein, or all three proteins rearrange during vesicle preparation.

Adenosine Triphosphatases↗