Isolation and characterization of rhizobiophages specific for Bradyrhizobium japonicum USDA 117

1986 ◽  
Vol 32 (4) ◽  
pp. 326-329 ◽  
Author(s):  
F. M. Hashem ◽  
J. S. Angle ◽  
P. A. Ristiano
Keyword(s):  
Bradyrhizobium Japonicum ◽  
Generation Time ◽  
Burst Size ◽  
Maximum Size ◽  
Acetylene Reduction Activity ◽  
Reduction Activity ◽  
Isolation And Characterization ◽  
Mutant Phage ◽  
Shoot Weight

The isolation and characterization of two phages specific for Bradyrhizobium japonicum USDA 117 are reported. The original phage was isolated from a Chester silt loam soil cropped to soybeans. A mutant of this isolate was obtained during long-term incubation in soil of the original isolate. Both phages were specific for B. japonicum USDA 117. The primary distinction between the two phages was the plaque size produced on the host. The original isolate produced plaques with a maximum size of 2.2 mm2. The mutant phage produced plaques with a maximum size of 11.4 mm2. Both phages exhibited similar morphologies. The head was hexagonal in shape with a diameter of 60 nm. An adsorption rate experiment revealed that the mutant phage was adsorbed faster to the host than the original isolate. Maximum adsorption of the original isolate to the host occurred after 10 min, while the mutant phage required 7 min. Characterization of the original isolate in a one-step growth experiment revealed that the burst size, rise period, and generation time were 100 plaque-forming units/cell, 12 min, and 80 min, respectively. A similar experiment for the mutant phage demonstrated a burst size, rise period, and generation time of 210 plaque-forming units/cell, 6 min, and 70 min, respectively. The ecological competitiveness of the mutant phage appeared to have been altered. In a greenhouse soil incubation experiment, the original isolate reduced nodule number, nodule weight, shoot weight, and acetylene reduction activity to a significantly greater extent than the mutant phage. These results indicate that, while the overall growth rate of the mutant phage was faster, it was less efficient in its parasitism of its host.

scholarly journals Carbohydrate binding activities of Bradyrhizobium japonicum. II. Isolation and characterization of a galactose-specific lectin.

1990 ◽  
Vol 111 (4) ◽  
pp. 1639-1643 ◽  
Author(s):  
S C Ho ◽  
M Schindler ◽  
J L Wang
Keyword(s):  
Isoelectric Focusing ◽  
Bradyrhizobium Japonicum ◽  
Affinity Column ◽  
Carbohydrate Binding ◽  
Binding Affinities ◽  
Isolation And Characterization ◽  
Relative Binding ◽  
Mannose Derivatives ◽  
Derivatives Of

Extracts of Bradyrhizobium japonicum were fractionated on Sepharose columns covalently derivatized with lactose. Elution of the material that was specifically bound to the affinity column with lactose yielded a protein of Mr approximately 38,000. Isoelectric focusing of this sample yielded two spots with pI values of 6.4 and 6.8. This protein specifically bound to galactose-containing glycoconjugates, but did not bind either to glucose or mannose. Derivatives of galactose at the C-2 position showed much weaker binding; there was an 18-fold difference in the relative binding affinities of galactose versus N-acetyl-D-galactosamine. These results indicate that we have purified a newly identified carbohydrate-binding protein from Bradyrhizobium japonicum, that can exquisitely distinguish galactose from its derivatives at the C-2 position.

scholarly journals Isolation and Characterization of a Bacteriophage Infecting Pseudomonas Aeruginosa and Its Application as a Potential Decontaminating Agent

2021 ◽  
Author(s):  
Sonika Sharma ◽  
Sibnarayan Datta ◽  
Soumya Chatterjee ◽  
Moumita Dutta ◽  
Jhuma Samanta ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Burst Size ◽  
Gc Content ◽  
Alginate Beads ◽  
Open Reading Frames ◽  
Isolation And Characterization ◽  
The Family ◽  
Infected Cells

Abstract To treat antibiotic resistance bacteria, bacteriophage (also called 'phage') application has recently drawn considerable attention from researchers globally. Bacteria like Pseudomonas aeruginosa are known to be associated with nosocomial infections especially in patients with compromised immune systems. In the present work, phage against P. aeruginosa (named 'DRLP1') was isolated from wastewater, enriched and characterized. Morphologically DRLP1 belongs to the family Myoviridae with a high lytic ability. DRLP1 has a burst size of approximately 100 PFU/infected cells, a rapid adsorption time when supplemented with MgCl2, and has viability in a wide temperature range and pH. Genomic sequencing and bioinformatics analysis showed that the phage genome is linear double-stranded, 66,243 bp in length and have a GC content of 54.9%. the genome encodes 93 phage related ORFs open reading frames (ORFs). Phage stability in lyophilized state, adsorption study on sodium alginate beads, and in-vitro pathogen reduction assays were also investigated. Study carried out with artificially contaminated fomites suggests that this phage has the potential for application as a biological decontaminant agent against P. aeruginosa in different conditions.

scholarly journals Isolation and characterization of a lytic bacteriophage against Pseudomonas aeruginosa

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sonika Sharma ◽  
Sibnarayan Datta ◽  
Soumya Chatterjee ◽  
Moumita Dutta ◽  
Jhuma Samanta ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Burst Size ◽  
Antibiotic Resistance Genes ◽  
Multidrug Resistant ◽  
Potential Candidate ◽  
Lytic Bacteriophage ◽  
Isolation And Characterization ◽  
Phage Proteins

AbstractIn recent years, the use of bacteriophages (or 'phages') against multidrug-resistant (MDR) bacteria including Pseudomonas aeruginosa has drawn considerable attention, globally. In this work, we report the isolation and detailed characterization of a highly lytic Pseudomonasphage DRL-P1 isolated from wastewater. Under TEM, DRL-P1 appeared as a member of the phage family Myoviridae. DRL-P1 featured rapid adsorption (~ 5 min), short-latency (~ 30 min), and large burst size (~ 100 PFU per infected cell). DRL-P1 can withstand a wide temperature range (4 °C to 40 °C) and pH (5.0 to 10.0) conditions. The 66,243 bp DRL-P1 genome (MN564818) encodes at least 93 ORFs, of which 36 were functionally annotated based on homology with similar phage proteins available in the databases. Comparative analyses of related genomes suggest an independent evolutionary history and discrete taxonomic position of DRL-P1 within genus Pbunavirus. No toxin or antibiotic resistance genes was identified. DRL-P1 is tolerant to lyophilization and encapsulation techniques and retained lytic activity even after 18 months of storage. We also demonstrated decontaminating potentials of DRL-P1 in vitro, on an artificially contaminated cover-slip model. To the best of our knowledge, this is the first Pbunavirus to be reported from India. Our study suggests DRL-P1 as a potential candidate for various applications.

scholarly journals Isolation and Characterization of a Competition-Defective Bradyrhizobium japonicum Mutant

1991 ◽  
Vol 57 (12) ◽  
pp. 3496-3501 ◽  
Author(s):  
Arvind A. Bhagwat ◽  
Raymond E. Tully ◽  
Donald L. Keister
Keyword(s):  
Bradyrhizobium Japonicum ◽  
Isolation And Characterization

scholarly journals Isolation and characterization of the DNA region encoding nodulation functions in Bradyrhizobium japonicum.

1985 ◽  
Vol 164 (3) ◽  
pp. 1301-1308 ◽  
Author(s):  
P Russell ◽  
M G Schell ◽  
K K Nelson ◽  
L J Halverson ◽  
K M Sirotkin ◽  
...  
Keyword(s):  
Bradyrhizobium Japonicum ◽  
Isolation And Characterization

scholarly journals Isolation and Characterization of Pectobacterium Phage vB_PatM_CB7: New Insights into the Genus Certrevirus

Antibiotics ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 352
Author(s):  
Colin Buttimer ◽  
Caoimhe Lynch ◽  
Hanne Hendrix ◽  
Horst Neve ◽  
Jean-Paul Noben ◽  
...  
Keyword(s):  
Sequence Similarity ◽  
Burst Size ◽  
Homing Endonuclease ◽  
Soft Rot ◽  
Nucleotide Metabolism ◽  
Homing Endonucleases ◽  
Isolation And Characterization ◽  
Rot Disease ◽  
Large Terminase

To date, Certrevirus is one of two genera of bacteriophage (phage), with phages infecting Pectobacterium atrosepticum, an economically important phytopathogen that causes potato blackleg and soft rot disease. This study provides a detailed description of Pectobacterium phage CB7 (vB_PatM_CB7), which specifically infects P. atrosepticum. Host range, morphology, latent period, burst size and stability at different conditions of temperature and pH were examined. Analysis of its genome (142.8 kbp) shows that the phage forms a new species of Certrevirus, sharing sequence similarity with other members, highlighting conservation within the genus. Conserved elements include a putative early promoter like that of the Escherichia coli sigma70 promoter, which was found to be shared with other genus members. A number of dissimilarities were observed, relating to DNA methylation and nucleotide metabolism. Some members do not have homologues of a cytosine methylase and anaerobic nucleotide reductase subunits NrdD and NrdG, respectively. Furthermore, the genome of CB7 contains one of the largest numbers of homing endonucleases described in a single phage genome in the literature to date, with a total of 23 belonging to the HNH and LAGLIDADG families. Analysis by RT-PCR of the HNH homing endonuclease residing within introns of genes for the large terminase, DNA polymerase, ribonucleotide reductase subunits NrdA and NrdB show that they are splicing competent. Electrospray ionization-tandem mass spectrometry (ESI-MS/MS) was also performed on the virion of CB7, allowing the identification of 26 structural proteins—20 of which were found to be shared with the type phages of the genera of Vequintavirus and Seunavirus. The results of this study provide greater insights into the phages of the Certrevirus genus as well as the subfamily Vequintavirinae.

scholarly journals Isolation and Characterization of Bacteriophages Infecting the Fish Pathogen Flavobacterium psychrophilum

2008 ◽  
Vol 74 (13) ◽  
pp. 4070-4078 ◽  
Author(s):  
Anne Rønnest Stenholm ◽  
Inger Dalsgaard ◽  
Mathias Middelboe
Keyword(s):  
Rainbow Trout ◽  
Cold Water ◽  
Burst Size ◽  
Latency Period ◽  
Broad Host Range ◽  
Flavobacterium Psychrophilum ◽  
Isolation And Characterization ◽  
Trout Farms ◽  
Host Strains

ABSTRACT Flavobacterium psychrophilum is a serious pathogen in trout aquaculture, responsible for the diseases rainbow trout fry syndrome (RTFS) and cold water disease (CWD). Bacteriophage control of F. psychrophilum may constitute a realistic approach in the treatment of these diseases; however, a detailed understanding of the phage-host interactions is needed to evaluate the potential of F. psychrophilum bacteriophages for that purpose. Twenty-two F. psychrophilum phages from Danish rainbow trout farms were isolated and characterized. The phage genome sizes differed considerably and fell into three major size classes (8.5 to 12 kb, 48 kb, and 90 kb). The phage host ranges comprised from 5 to 23 of the 28 tested F. psychrophilum strains, and 18 of the phage isolates showed unique host ranges. Each bacterial strain had a unique pattern of susceptibility to the 22 phages, and individual strains also showed large variations (up to 107-fold differences) in susceptibility to specific phages. Phage burst size (7 to 162 phages infected cell−1) and latency period (4 to 6 h) also showed pronounced differences both between phages and, for a specific phage, between host strains. In general, the characterization documented the presence of diverse F. psychrophilum phage communities in Danish trout farms, with highly variable patterns of infectivity. The discovery and characterization of broad-host-range phages with strong lytic potential against numerous pathogenic F. psychrophilum host strains thus provided the foundation for future exploration of the potential of phages in the treatment of RTFS and CWD.

scholarly journals Isolation and Characterization of Phages InfectingBacillus subtilis

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Anna Krasowska ◽  
Anna Biegalska ◽  
Daria Augustyniak ◽  
Marcin Łoś ◽  
Malwina Richert ◽  
...  
Keyword(s):  
Food Production ◽  
Burst Size ◽  
Industrial Applications ◽  
Isolation And Characterization ◽  
Latent Time ◽  
Food Borne ◽  
Alternative Approach ◽  
Sds Page

Bacteriophages have been suggested as an alternative approach to reduce the amount of pathogens in various applications. Bacteriophages of various specificity and virulence were isolated as a means of controlling food-borne pathogens. We studied the interaction of bacteriophages withBacillusspecies, which are very often persistent in industrial applications such as food production due to their antibiotic resistance and spore formation. A comparative study using electron microscopy, PFGE, and SDS-PAGE as well as determination of host range, pH and temperature resistance, adsorption rate, latent time, and phage burst size was performed on three phages of theMyoviridaefamily and one phage of theSiphoviridaefamily which infectedBacillus subtilisstrains. The phages are morphologically different and characterized by icosahedral heads and contractile (SIOΦ, SUBω, and SPOσphages) or noncontractile (ARπphage) tails. The genomes of SIOΦ and SUBωare composed of 154 kb. The capsid of SIOΦ is composed of four proteins. Bacteriophages SPOσand ARπhave genome sizes of 25 kbp and 40 kbp, respectively. Both phages as well as SUBωphage have 14 proteins in their capsids. Phages SIOΦ and SPOσare resistant to high temperatures and to the acid (4.0) and alkaline (9.0 and 10.0) pH.

Cloning and characterization of the nifA gene from Herbaspirillum seropedicae strain Z78

1991 ◽  
Vol 37 (6) ◽  
pp. 425-429 ◽  
Author(s):  
Emanuel M. Souza ◽  
Shigehiro Funayama ◽  
Liu U. Rigo ◽  
Fábio O. Pedrosa
Keyword(s):  
Nitrogen Fixation ◽  
Azospirillum Brasilense ◽  
Genomic Library ◽  
Acetylene Reduction Activity ◽  
Nif Genes ◽  
Herbaspirillum Seropedicae ◽  
Reduction Activity ◽  
Nitrogen Fixation Gene ◽  
Nifa Gene

A genomic library of Herbaspirillum seropedicae was constructed and screened for the nifA gene by complementation of a nifA mutant of Azospirillum brasilense (FP10). A recombinant plasmid, pEMS1, capable of restoring acetylene reduction activity in the mutant FP10, was isolated and found to hybridize to the nifA gene of Klebsiella pneumoniae. The results suggest that nifA is involved in the regulation of nif genes in H. seropedicae. Key words: diazotroph, nitrogen fixation gene, nif regulation, complementation cloning, Herbaspirillum seropedicae.

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