Characterization of Myoviridae and Podoviridae family bacteriophages of Erwinia amylovora from Hungary - potential of application in biological control of fire blight

Abstract Together with genome analysis and knock-out mutants, structural and functional characterization of proteins provide valuable hints on the biology of the organism under investigation. Structural characterization can be achieved by techniques such as X-ray crystallography, NMR, Cryo-EM. The information derived from the structure are a good starting point to comprehend the details of the proteins molecular function for a better understanding of their biological role. This review aims at describing the progress in the structural and functional characterization of proteins from the plant pathogen Erwinia amylovora obtained by structural biology and currently deposited in the Protein Data Bank.

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MICROARRAY CHARACTERIZATION OF THE HRPL REGULON OF THE FIRE BLIGHT PATHOGEN ERWINIA AMYLOVORA

Acta Horticulturae ◽

10.17660/actahortic.2011.896.36 ◽

2011 ◽

pp. 263-270

Author(s):

R.R. McNally ◽

G.W. Sundin ◽

Y.F. Zhao ◽

I.K. Toth ◽

P.J.A. Cock ◽

...

Keyword(s):

Fire Blight ◽

Erwinia Amylovora

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Characterization of Serracin P, a Phage-Tail-Like Bacteriocin, and Its Activity against Erwinia amylovora, the Fire Blight Pathogen

Applied and Environmental Microbiology ◽

10.1128/aem.68.11.5704-5710.2002 ◽

2002 ◽

Vol 68 (11) ◽

pp. 5704-5710 ◽

Cited By ~ 54

Author(s):

Abdelhamid Jabrane ◽

Ahmed Sabri ◽

Philippe Compère ◽

Philippe Jacques ◽

Isabel Vandenberghe ◽

...

Keyword(s):

Fire Blight ◽

Erwinia Amylovora ◽

Culture Supernatant ◽

Bacterial Disease ◽

Amino Acid Sequence Analysis ◽

Terminal Amino Acid ◽

Phage Tail ◽

Terminal Amino ◽

Pear Trees

ABSTRACT Serratia plymithicum J7 culture supernatant displayed activity against many pathogenic strains of Erwinia amylovora, the causal agent of the most serious bacterial disease of apple and pear trees, fire blight, and against Klebsiella pneumoniae, Serratia liquefaciens, Serratia marcescens, and Pseudomonas fluorescens. This activity increased significantly upon induction with mitomycin C. A phage-tail-like bacteriocin, named serracin P, was purified from an induced culture supernatant of S. plymithicum J7. It was found to be the only compound involved in the antibacterial activity against sensitive strains. The N-terminal amino acid sequence analysis of the two major subunits (23 and 43 kDa) of serracin P revealed high homology with the Fels-2 prophage of Salmonella enterica, the coliphages P2 and 168, the φCTX prophage of Pseudomonas aeruginosa, and a prophage of Yersinia pestis. This strongly suggests a common ancestry for serracin P and these bacteriophages.

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Control of Fire Blight by Pseudomonas fluorescens A506 and Pantoea vagans C9-1 Applied as Single Strains and Mixed Inocula

Phytopathology ◽

10.1094/phyto-03-10-0097 ◽

2010 ◽

Vol 100 (12) ◽

pp. 1330-1339 ◽

Cited By ~ 50

Author(s):

V. O. Stockwell ◽

K. B. Johnson ◽

D. Sugar ◽

J. E. Loper

Keyword(s):

Biological Control ◽

Pseudomonas Fluorescens ◽

Fire Blight ◽

Erwinia Amylovora ◽

Field Trials ◽

Disease Suppression ◽

Biological Control Agents ◽

Population Sizes ◽

Mixed Inocula ◽

Pantoea Vagans

The biological control agents Pseudomonas fluorescens A506 and Pantoea vagans C9-1 were evaluated individually and in combination for the suppression of fire blight of pear or apple in 10 field trials inoculated with the pathogen Erwinia amylovora. The formulation of pathogen inoculum applied to blossoms influenced establishment of the pathogen and the efficacy of biological control. Pantoea vagans C9-1 suppressed fire blight in all five trials in which the pathogen was applied as lyophilized cells but in none of the trials in which the pathogen was applied as freshly harvested cells. In contrast, Pseudomonas fluorescens A506 reduced disease significantly in only one trial. A mixture of the two strains also suppressed fire blight, but the magnitude of disease suppression over all field trials (averaging 32%) was less than that attained by C9-1 alone (42%). The two biological control agents did not antagonize one another on blossom surfaces, and application of the mixture of A506 and C9-1 to blossoms resulted in a greater proportion of flowers having detectable populations of at least one bacterial antagonist than the application of individual strains. Therefore, the mixture of A506 and C9-1 provided less disease control than expected based upon the epiphytic population sizes of the antagonists on blossom surfaces. We speculate that the biocontrol mixture was less effective than anticipated due to incompatibility between the mechanisms by which A506 and C9-1 suppress disease.

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Characterization of AcrD, a Resistance-Nodulation-Cell Division-type multidrug efflux pump from the fire blight pathogen Erwinia amylovora

BMC Microbiology ◽

10.1186/1471-2180-14-13 ◽

2014 ◽

Vol 14 (1) ◽

pp. 13 ◽

Cited By ~ 15

Author(s):

Daniel Pletzer ◽

Helge Weingart

Keyword(s):

Cell Division ◽

Fire Blight ◽

Erwinia Amylovora ◽

Efflux Pump ◽

Multidrug Efflux ◽

Multidrug Efflux Pump

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Bee Vectoring: Development of the Japanese Orchard Bee as a Targeted Delivery System of Biological Control Agents for Fire Blight Management

Pathogens ◽

10.3390/pathogens9010041 ◽

2020 ◽

Vol 9 (1) ◽

pp. 41 ◽

Cited By ~ 1

Author(s):

Neelendra K. Joshi ◽

Henry K. Ngugi ◽

David J. Biddinger

Keyword(s):

Biological Control ◽

Targeted Delivery ◽

Fire Blight ◽

Erwinia Amylovora ◽

The United States ◽

Biocontrol Agents ◽

Efficient System ◽

Control Product ◽

Tree Fruits ◽

Potential Use

Fire blight, which is caused by the bacteria Erwinia amylovora, remains one of the most important diseases limiting the productivity of apple and pear orchards in the United States. In commercial orchards, in-season fire blight management relies exclusively on the use of antibiotic treatments (such as streptomycin and oxytetracycline) and on bacterial biocontrol agents whose efficacy is limited. We hypothesize that the efficacy of the biocontrol agents can be greatly enhanced through targeted delivery to flowers, which serve as initial infection courts, using the Japanese orchard bee, Osmia cornifrons. Many factors, such as the synchrony of life cycle with plant phenology and specificity to pomaceous plants, suggest that O. cornifrons could be an excellent vector of the biocontrol products during bloom in pome tree fruits. However, deployment of this pollinator species to deliver biocontrol agents for fire blight control has not been attempted previously due to the lack of an efficient system to pack the bodies of the bees exiting nesting tubes with the biocontrol products. In this study, we design and test a dispenser system to facilitate the use of O. conifrons as a vector for commercially available biocontrol products for fire blight control. The effectiveness of O. conifrons to deliver biocontrol agents to flowers, and to effect secondary dissemination from treated to untreated flowers is also evaluated in greenhouse experiments. We found that the O. conifrons bees were able to use the nest dispenser designed for the delivery of biological control products, and are effective in vectoring and delivering the Bacillus subtilis-based biological control product (Serenade®) to apple blossoms. We also found that the O. cornifrons were effective in secondary inoculation of this biological control product to newly-opened flowers. These findings suggest the potential use of commercially available O. conifrons and other orchard bees in targeted delivery of biological control products for fire blight, and possibly other diseases, in different fruit crops.

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Influence of Age of Apple Flowers on Growth of Erwinia amylovora and Biological Control Agents

Plant Disease ◽

10.1094/pdis.2003.87.5.502 ◽

2003 ◽

Vol 87 (5) ◽

pp. 502-509 ◽

Cited By ~ 25

Author(s):

S. V. Thomson ◽

S. C. Gouk

Keyword(s):

Biological Control ◽

Fire Blight ◽

Erwinia Amylovora ◽

Antagonistic Bacteria ◽

Biological Control Agents ◽

Limited Growth ◽

Bacterial Populations ◽

Arid Conditions ◽

Flower Age ◽

Causal Pathogen

The influence of flower age on growth of Erwinia amylovora, the causal pathogen of fire blight of apples and pears, was investigated under humid and arid conditions in Hamilton, New Zealand (NZ), and Logan, UT, USA, respectively. ‘Royal Gala’ apple flowers ranging from 1 to 8 days old were atomized with E. amylovora. Pistils were dissected and washed separately from the remaining floral parts (flowers ex pistils) for estimation of bacterial numbers. Pistils, 1 to 3 days old (USA) and 1 to 4 days old (NZ), supported exponential growth of E. amylovora, but bacterial populations did not increase when older flowers were inoculated. Scanning electron microscopy showed round and turgid papillae on stigmas of 1-day-old flowers. Papillae on 4- to 6-day-old stigmas were completely collapsed and covered in mucilage. Populations of E. amy-lovora on the flowers ex pistils were characteristically lower than pistil populations. High populations of saprophytic bacteria were found on both floral parts of all ages, but there was no difference in their numbers on 3- to 6-day-old pistils. This suggests their presence did not inhibit the growth of E. amylovora on older stigmas. The results demonstrate that stigmas on 1- to 3-day-old flowers often support rapid growth of E. amylovora, but flowers inoculated when more than 4 to 5 days old do not support growth or only limited growth. The same location and pattern of bacterial growth occurred with the biological control agents Pseudomonas fluorescens PfA506n and Pantoea agglomerans (Erwinia herbicola) Eh318nr. The distinct effect of flower age on growth of antagonistic bacteria and E. amylovora may be important in deciding when to treat with biological control organisms or bactericides.

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Testing the virulence of some Hungarian Erwinia amylovora strains on in vitro cultured apple rootstocks

International Journal of Horticultural Science ◽

10.31421/ijhs/6/4/223 ◽

2000 ◽

Vol 6 (4) ◽

Cited By ~ 7

Author(s):

M. Hevesi ◽

J. Papp ◽

E. Jámbor-Benczúr ◽

K. Kaszáné Csizmár ◽

I. Pozsgai ◽

...

Keyword(s):

Host Plants ◽

Fire Blight ◽

Erwinia Amylovora ◽

Disease Development ◽

Apple Rootstocks ◽

Disease Rating ◽

Different Strains

A useful method was improved to test and to evaluate the susceptibility of plants to fire blight and the virulence of E. amylovora strains. Six Hungarian strains from different host plants were tested on in vitro cultured apple rootstocks. Disease rating was used for the characterization of the process of disease development. The different strains had different capacity to cause disease, mainly in the first period of incubation. There were significant differences between the virulence of the strains.

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