Partial characterization of a new C3-type capsule-dissolving phage of Streptococcus cremoris

Maija-Liisa Saxelin; Eeva-Liisa Nurmiaho; M. P. Korhola; Veronica Sundman

doi:10.1139/m79-183

Partial characterization of a new C3-type capsule-dissolving phage of Streptococcus cremoris

Canadian Journal of Microbiology ◽

10.1139/m79-183 ◽

1979 ◽

Vol 25 (10) ◽

pp. 1182-1187 ◽

Cited By ~ 18

Author(s):

Maija-Liisa Saxelin ◽

Eeva-Liisa Nurmiaho ◽

M. P. Korhola ◽

Veronica Sundman

Keyword(s):

Latent Period ◽

Burst Size ◽

Buoyant Density ◽

Partial Characterization ◽

Milk Product ◽

Streptococcus Cremoris ◽

Sour Milk ◽

Average Burst Size

A viscous, ropy, sour milk product, called 'viili,' is produced in Finland. Capsule-forming strains of Streptococcus cremoris are the typical starters for this product. Occasionally fermentation fails and results in a non-ropy clot. The reasons for these failures, however, are obscure. In one batch of spoiled 'viili,' a new C3-type bacteriophage, termed KSY1, was isolated. The head of the phage was about 230 nm long and about 50 nm wide and the tail was 35 nm long and carried a complex collar structure. Upon infection of a number of encapsulated cultures of S. cremoris with KSY1, the cocci, though not serving as a host of the phage, lost their capsules. A capsuleless strain, S. cremoris 249, served as a host. The latent period was about 150 min and the average burst size 80. The buoyant density of KSY1 was 1.436 g/cm3.

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Partial characterization of a cubic Bacillus phage

Canadian Journal of Microbiology ◽

10.1139/m78-162 ◽

1978 ◽

Vol 24 (8) ◽

pp. 986-993 ◽

Cited By ~ 41

Author(s):

H.-W. Ackermann ◽

R. Roy ◽

M. Martin ◽

M. R. V. Murthy ◽

W. A. Smirnoff

Keyword(s):

Drug Resistance ◽

Nucleic Acid ◽

Latent Period ◽

Burst Size ◽

Partial Characterization ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Resistance Plasmids ◽

Bacillus Phage

Phage Bam35 is an icosahedron of about 63 nm in diameter. It has a double capsid with spikes at the vertices, and a tail which seems to appear upon nucleic acid ejection. The phage contains DNA and, probably, lipids which seem to be located in the inner coat. The phage is Bacillus-specific, UV- and lipase-resistant, and sensitive to heat, chloroform, and ether. The latent period is 50 min and the burst size is 39. Phage Bam35 belongs to a new virus group which includes a phage of B. anthracis and four phages of gram-negative bacteria harboring drug-resistance plasmids.

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Isolation and partial characterization of high-buoyant-density proteoglycans synthesized in ovo by embryonic chick skeletal muscle and heart.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)90763-5 ◽

1984 ◽

Vol 259 (20) ◽

pp. 12419-12430

Author(s):

D A Carrino ◽

A I Caplan

Keyword(s):

Skeletal Muscle ◽

Buoyant Density ◽

Partial Characterization ◽

Embryonic Chick ◽

In Ovo

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INFLUENCE OF SELECTED HERBICIDES IN PHAGES OF SOME SOIL BACTERIA

Canadian Journal of Soil Science ◽

10.4141/cjss82-024 ◽

1982 ◽

Vol 62 (1) ◽

pp. 217-220 ◽

Cited By ~ 2

Author(s):

E. B. ROSLYCKY

Keyword(s):

Latent Period ◽

Soil Bacteria ◽

Rhizobium Meliloti ◽

Burst Size ◽

Lytic Activity ◽

Agrobacterium Radiobacter ◽

Host System ◽

Average Burst Size ◽

Homologous Antiserum ◽

Particle Attachment

Various concentrations of paraquat, atrazine, simazine, linuron, diuron, and paraquat in combinations with each including simazine + diuron, and terbacil alone, did not inhibit lytic activity of four bacteriophages of Agrobacterium radiobacter, three bacteriophages of Rhizobium meliloti, three bacteriophages of R. trifolii, or two bacteriophages of Streptomyces chrysomallus. Generally, the herbicides had no effect on the neutralization of radiobacterphage PR-1001 with its homologous antiserum, the length of the latent period, the percent adsorption or the average burst size. In contrast, paraquat concentrations from 20 to 400 μg∙mL−1 gradually reduced the adsorption from 38 to 21% and the average burst size from 67 to 9 in the PR-1001:R-1001 phage: host system. The same concentrations, however, showed no effect on the particle attachment or the length of the latent period.

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Isolation and characterization of wetland VSW-3, a novel lytic cold-active bacteriophage of Pseudomonas fluorescens

Canadian Journal of Microbiology ◽

10.1139/cjm-2016-0368 ◽

2017 ◽

Vol 63 (2) ◽

pp. 110-118 ◽

Cited By ~ 6

Author(s):

Kunhao Qin ◽

Xiuling Ji ◽

Chunjing Zhang ◽

Yafang Ding ◽

Anxiu Kuang ◽

...

Keyword(s):

Pseudomonas Fluorescens ◽

Burst Size ◽

Isolation And Characterization ◽

A Genome ◽

Cold Active ◽

Average Burst Size ◽

20 Nm ◽

High Degree ◽

Thermal Stability Of

Wetlands are often called the “kidneys of the Earth” and contribute substantially to environmental improvement. Pseudomonas fluorescens is a major contaminant of milk products and causes the spoilage of refrigerated foods and fresh poultry. In this study, we isolated and characterized a lytic cold-active bacteriophage named VSW-3 together with P. fluorescens SW-3 cells from the Napahai wetland in China. Electron microscopy showed that VSW-3 had an icosahedral head (56 nm) and a tapering tail (20 nm × 12 nm) and a genome size of approximate 40 kb. On the basis of the top-scoring hits in the BLASTP analysis, VSW-3 showed a high degree of module similarity to the Pseudomonas phages Andromeda and Bf7. The latent and burst periods were 45 and 20 min, respectively, with an average burst size of 90 phage particles per infected cell. The pH and thermal stability of VSW-3 were also explored. The optimal pH was found to be 7.0 and the activity decreased rapidly when the temperature exceeded 60 °C. VSW-3 is a cold-active bacteriophage, hence, it is important to research its ability to prevent product contamination caused by P. fluorescens and to characterize its relationship with its host P. fluorescens in the future.

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Characterization of Bacteriophages Targeting Non-O157 Shiga Toxigenic Escherichia coli

Journal of Food Protection ◽

10.4315/0362-028x.jfp-17-460 ◽

2018 ◽

Vol 81 (5) ◽

pp. 785-794 ◽

Cited By ~ 5

Author(s):

PUSHPINDER KAUR LITT ◽

JOYJIT SAHA ◽

DIVYA JARONI

Keyword(s):

Escherichia Coli ◽

Latent Period ◽

Foodborne Pathogens ◽

Food Industry ◽

Control Strategies ◽

Burst Size ◽

Effective Control ◽

Attractive Alternative ◽

C Storage

ABSTRACT Non-O157 Shiga toxigenic Escherichia coli (STEC) are an important group of foodborne pathogens, implicated in several outbreaks and recalls in the past 2 decades. It is therefore crucial to devise effective control strategies against these pathogens. Bacteriophages present an attractive alternative to conventional pathogen control methods in the food industry. Bacteriophages, targeting non-O157 STEC (O26, O45, O103, O111, O121, O145), were isolated from beef cattle operations in Oklahoma. Their host range and lytic ability were determined against several (n = 21) non-O157 STEC isolates, by using the spot-on-lawn assay. Isolated phages were purified, and their morphology was determined under a transmission electron microscope. Infection kinetics of selected phages (n = 19), particularly adsorption rate, rise period, latent period, and burst size, were determined. Phages were also evaluated for stability at a wide pH range (1 to 11) and temperature range (−80 to 90°C). In total, 45 phages were isolated and classified into Myoviridae, Siphoviridae, or Tectiviridae. The phages had a latent period between 8 and 37 min, a rise period between 19 and 40 min, and a large burst size (12 to 794 virions per infected cell), indicating high lytic activity. Tested phages were stable at pH 5 to 9 for 24 h, whereas a decrease in phage titer was observed at pHs 1, 2, and 11. Phages were stable at 40 and 60°C, except for O103-specific phages. At 70°C, all the phages lost viability after 20 min, except three phages targeting O26 and O121 and one phage targeting O45 and O111 STEC, which remained viable for 60 min. All the phages lost activity after 10 min at 90°C, except one each of O26 and O121 STEC–infecting phages that remained viable for 60 min. Phages remained stable for 90 days under refrigerated (4°C) and frozen (−20 and −80°C) storage. Characterization of phages, targeting diverse non-O157 STEC serotypes, could help in the development of effective biocontrol strategies for this group of pathogens in the food industry.

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Isolation and Characterization of an Aeromonas punctata Bacteriophage

The Open Biomedical Engineering Journal ◽

10.2174/1874120701509010185 ◽

2015 ◽

Vol 9 (1) ◽

pp. 185-187 ◽

Cited By ~ 1

Author(s):

Cheng Kai ◽

Zhang Denglan ◽

Deng Jingxuan ◽

Zhao Yijun

Keyword(s):

Restriction Enzyme ◽

Burst Size ◽

Wuhan City ◽

Isolation And Characterization ◽

Double Stranded Dna ◽

East Lake ◽

Average Burst Size ◽

Enzyme Pattern ◽

Restriction Enzyme Pattern

AnAeromonas punctatabacteriophage, named as DH1, was isolated from East Lake, Wuhan city, China. Morphologically, phage DH1 showed a typicalMyoviridaestructure consisting of an isometric head (50 nm in diameter) and a visible tail. The bacteriophage had a latent period of about 90 minutes and an average burst size of about 125 PFU•Cell-1. Restriction enzyme pattern of the bacteriophage’s genome showed that the genome is a double-stranded DNA and about 34kb in size. The sequenced genomic fragments showed highly similarities to gp04 and gp16 sequence of otherMyoviridaebacteriophages at protein level.

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Isolation and characterization of two bacteriophages of a stem-nodulating Rhizobium strain from Sesbania rostrata

Canadian Journal of Microbiology ◽

10.1139/m84-079 ◽

1984 ◽

Vol 30 (5) ◽

pp. 521-525 ◽

Cited By ~ 11

Author(s):

Philippe de Lajudie ◽

Didier Bogusz

Keyword(s):

Burst Size ◽

Growth Cycle ◽

Sesbania Rostrata ◽

Isolation And Characterization ◽

Rhizobium Strains ◽

One Step ◽

Average Burst Size ◽

Step Growth ◽

Phage Growth

Two rhizobiophages, RS1 and RS2, were isolated in Senegal from a soil sample and dry stem nodules of Sesbania rostrata, a tropical legume that is infected by two categories of Rhizobium strains: "stem strains," which nodulate both roots and stems (type strain, ORS571), and "root strains," which induce effective nodules only on roots. Both phages were found to have a host range restricted to ORS571; all root strains were found to be resistant. By electron microscopy, phage RS1 showed an hexagonal head 63 nm wide and a tail 87 nm long; phage RS2 revealed an hexagonal head 60 nm wide. Characterization of phage growth cycle by one-step growth experiments showed that the latent period was ca. 75 min for RS1 and ca. 4 h for RS2, that the rise period lasted ca. 2 h for both RS1 and RS2, and that the average burst size was ca. 100 for RS1 and 130 for RS2. Temperature denaturation occurred at 60–65 °C (RS1) and 45–50 °C (RS2). Serum neutralization tests revealed that the phages were not serologically related. In contrast to RS1, RS2 appeared to be temperate, since stable lysogens were isolated.

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THE GROWTH OF BACTERIOPHAGE

The Journal of General Physiology ◽

10.1085/jgp.22.3.365 ◽

1939 ◽

Vol 22 (3) ◽

pp. 365-384 ◽

Cited By ~ 380

Author(s):

Emory L. Ellis ◽

Max Delbrück

Keyword(s):

Latent Period ◽

Phage Particle ◽

Burst Size ◽

Plaque Formation ◽

Late Time ◽

Counting Method ◽

Average Burst Size ◽

The Individual ◽

Escherichia Coli Phage ◽

Bacterium Growth

1. An anti-Escherichia coli phage has been isolated and its behavior studied. 2. A plaque counting method for this phage is described, and shown to give a number of plaques which is proportional to the phage concentration. The number of plaques is shown to be independent of agar concentration, temperature of plate incubation, and concentration of the suspension of plating bacteria. 3. The efficiency of plating, i.e. the probability of plaque formation by a phage particle, depends somewhat on the culture of bacteria used for plating, and averages around 0.4. 4. Methods are described to avoid the inactivation of phage by substances in the fresh lysates. 5. The growth of phage can be divided into three periods: adsorption of the phage on the bacterium, growth upon or within the bacterium (latent period), and the release of the phage (burst). 6. The rate of adsorption of phage was found to be proportional to the concentration of phage and to the concentration of bacteria. The rate constant ka is 1.2 x 10–9 cm.8/min. at 15°C. and 1.9 x 10–9 cm.8/min. at 25°. 7. The average latent period varies with the temperature in the same way as the division period of the bacteria. 8. The latent period before a burst of individual infected bacteria varies under constant conditions between a minimal value and about twice this value. 9. The average latent period and the average burst size are neither increased nor decreased by a fourfold infection of the bacteria with phage. 10. The average burst size is independent of the temperature, and is about 60 phage particles per bacterium. 11. The individual bursts vary in size from a few particles to about 200. The same variability is found when the early bursts are measured separately, and when all the bursts are measured at a late time.

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