Complete genome resources for Xylella fastidiosa strains AlmaEM3 and BB08-1 reveal prophage-associated structural variation among blueberry-infecting strains.

Xylella fastidiosa is a gram-negative plant pathogenic bacterium with wide geographical distribution and host range. X. fastidiosa strains are separated into genetically distinct subspecies, and further categorized into sequence types (ST). Genetic characterization of X. fastidiosa strains infecting blueberry has revealed that strains of subspecies multiplex and fastidiosa are capable of causing bacterial leaf scorch disease of blueberry under field conditions. To better elucidate the relationships among blueberry-infecting X. fastidiosa subsp. multiplex strains, we completed the genomes of an ST 42 strain, AlmaEM3, and a ST 43 strain, BB08-1, using a hybrid assembly approach. Comparison of these assemblies reveals a large (0.95 Mb) chromosomal inversion in BB08-1 relative to AlmaEM3 and the reference strain M12, likely resulting from recombination between prophage regions.

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Genetic characterization of Xylella fastidiosa isolated from citrus and coffee plants

Scientia Agricola ◽

10.1590/s0103-90162007000500005 ◽

2007 ◽

Vol 64 (5) ◽

pp. 482-485 ◽

Cited By ~ 1

Author(s):

Vicente Savonitti Miranda ◽

Paulo Roberto Silva Farias ◽

Sérgio Rufo Roberto ◽

Pedro Magalhães Lacava

Keyword(s):

Genetic Characterization ◽

Xylella Fastidiosa ◽

Random Amplified Polymorphic Dna ◽

Negative Bacterium ◽

Similarity Coefficients ◽

Gram Negative ◽

Coffee Plants ◽

The Many ◽

Group D

The Citrus Variegated Chlorosis and the Coffee Leaf Scorch are some of the many destructive diseases caused by Xylella fastidiosa, a gram-negative bacterium limited to the xylem of affected plants. As its genetic characterization is still not well established, different isolates of X. fastidiosa from citrus and coffee were evaluated through RAPD (Random Amplified Polymorphic DNA) technique to characterize and classify these isolates based on similarity coefficients. Sixteen isolates of X. fastidiosa were used on this trial, obtained from citrus, coffee and almond. The genetic polymorphism evaluation was performed using six arbitrary 10-base primer pairs. It was possible to establish a dendogram in which the isolates were classified into five groups (A, B, C, D and E). A prevalence of citrus isolates in groups A and D was observed. In groups B and C, there was a prevalence of coffee isolates meanwhile the group D consisted of the almond isolate, solely.

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Genetic characterization of pathogenic fluorescent pseudomonads isolated from necrotic cherry and plum buds in Serbia

Genetika ◽

10.2298/gensr1303953g ◽

2013 ◽

Vol 45 (3) ◽

pp. 953-961 ◽

Cited By ~ 1

Author(s):

Veljko Gavrilovic ◽

Zarko Ivanovic ◽

Tatjana Popovic ◽

Svetlana Zivkovic ◽

Slavisa Stankovic ◽

...

Keyword(s):

Reference Strain ◽

Genetic Characterization ◽

Natural Infection ◽

Fluorescent Pseudomonads ◽

Necrotic Tissue ◽

Bacterial Strains ◽

Gram Negative ◽

Negative Results ◽

One Year

During past few years a symptoms of plum and cherry bud necrosis were observed in some regions with significant cherry production in Serbia. Gram negative, fluorescent, oxidative bacterial strains were isolated from the margin of necrotic tissue. All investigated strains are levan and HR positive, while negative results are recorded in oxidase, pectinase and arginin dihydrolase tests (LOPAT+---+). Symptoms similar to those observed in natural infection were obtained after artificial inoculation of cherry leaf scares and dormant one year old cherry shoots. Investigated strains as well as reference strain of P. syringae pv. morsprunorum cause the superficial necrosis on artificially inoculated immature cherry fruits, but negative results were recorded in immature pear and lemon fruit tests as well as syringae leaves and bean pods. Gelatin and aesculin tests were negative and tyrosinase and tartrate were positive. Investigated strains isolated from necrotic cherry buds had identical REP-PCR pattern with reference strain of P. syringae pv. morsprunorum. On the basis of obtained results, it was concluded that this bacterium is causal agent of cherry trees bud necrosis in Serbia.

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Localization and characterization of Xylella fastidiosa haemagglutinin adhesins

Microbiology ◽

10.1099/mic.0.037564-0 ◽

2010 ◽

Vol 156 (7) ◽

pp. 2172-2179 ◽

Cited By ~ 35

Author(s):

Tanja M. Voegel ◽

Jeremy G. Warren ◽

Ayumi Matsumoto ◽

Michele M. Igo ◽

Bruce C. Kirkpatrick

Keyword(s):

Molecular Mass ◽

Outer Membrane ◽

Biofilm Formation ◽

Xylella Fastidiosa ◽

Membrane Vesicles ◽

Cell Aggregation ◽

Pathogenic Bacterium ◽

Plant Pathogenic Bacterium ◽

Gram Negative

Xylella fastidiosa is a Gram-negative, xylem-inhabiting, plant-pathogenic bacterium responsible for several important diseases including Pierce's disease (PD) of grapevines. The bacteria form biofilms in grapevine xylem that contribute to the occlusion of the xylem vessels. X. fastidiosa haemagglutinin (HA) proteins are large afimbrial adhesins that have been shown to be crucial for biofilm formation. Little is known about the mechanism of X. fastidiosa HA-mediated cell–cell aggregation or the localization of the adhesins on the cell. We generated anti-HA antibodies and show that X. fastidiosa HAs are present in the outer membrane and secreted both as soluble proteins and in membrane vesicles. Furthermore, the HA pre-proteins are processed from the predicted molecular mass of 360 kDa to a mature 220 kDa protein. Based on this information, we are evaluating a novel form of potential resistance against PD by generating HA-expressing transgenic grapevines.

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Natural Infection of Southern Highbush Blueberry (Vaccinium corymbosum Interspecific Hybrids) by Xylella fastidiosa subsp. fastidiosa

Plant Disease ◽

10.1094/pdis-11-19-2477-re ◽

2020 ◽

Vol 104 (10) ◽

pp. 2598-2605

Author(s):

Dario Di Genova ◽

Kippy J. Lewis ◽

Jonathan E. Oliver

Keyword(s):

Genetic Characterization ◽

Xylella Fastidiosa ◽

Natural Infection ◽

Vaccinium Corymbosum ◽

Significant Similarity ◽

Potential Impact ◽

Southern Highbush ◽

Southern Georgia ◽

First Time

Xylella fastidiosa (Xf) is an emerging insect-vectored, xylem-limited bacterium that can cause disease on several economically important fruit and tree crops including almond, blueberry, citrus, grapevine, peach, and pecan. On blueberry, Xf causes bacterial leaf scorch (BLS), which is prevalent in the southeastern United States. This disease, previously reported to be caused by Xf subsp. multiplex (Xfm), can result in rapid plant decline and death of southern highbush (SHB) blueberry cultivars. In 2017, a survey of blueberry plantings in southern Georgia (U.S.A.) confirmed the presence of Xf-infected plants in eight of nine sites examined, and seven isolates were cultured from infected plants. Genetic characterization of these isolates through single-locus and multilocus sequence analysis revealed that three isolates from two sites belonged to Xf subsp. fastidiosa (Xff), with significant similarity to isolates from grapevine. After these three isolates were artificially inoculated onto greenhouse-grown SHB blueberries (cv. ‘Rebel’), symptoms typical of BLS developed, and Xff infection was confirmed through genetic characterization and reisolation of the bacterium to fulfill Koch’s postulates. Because all previously reported Xf isolates from blueberry have been characterized as Xfm, this is the first time that isolation of Xff has been reported from naturally infected blueberry plantings. The potential impact of Xff isolates on disease management in blueberry requires further exploration. Furthermore, given that isolates from both Xfm and Xff were obtained within a single naturally infected blueberry planting, blueberry in southern Georgia may provide opportunities for intersubspecific recombination between Xff and Xfm isolates.

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Phenotypic and Genetic Characterization of Carbapenemase and ESBLs Producing Gram-negative Bacteria (GNB) Isolated from Patients with Cystic Fibrosis in Tehran Tospitals

JOURNAL FOR CLINICAL AND DIAGNOSTIC RESEARCH ◽

10.7860/jcdr/2014/6877.3916 ◽

2014 ◽

Cited By ~ 3

Author(s):

Fereshteh Shahcheraghi

Keyword(s):

Cystic Fibrosis ◽

Genetic Characterization ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Phenotypic And Genetic Characterization

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Genetic Characterization of Plasmid-mediated qepA Gene Among ESBL-producing Escherichia Coli Isolates in Mexico

10.21203/rs.3.rs-547553/v1 ◽

2021 ◽

Author(s):

Humberto Barrios-Camacho ◽

Josefina Duran-Bedolla ◽

Jesus Silva-Sanchez ◽

Luis Lozano-Aguirre ◽

Fernando Reyna-Flores ◽

...

Keyword(s):

Escherichia Coli ◽

Molecular Characterization ◽

Genetic Characterization ◽

Insertion Sequences ◽

Plasmid Sequence ◽

E Coli ◽

Multiple Copies ◽

Chromosomal Mutations ◽

Sequence Types

Abstract A molecular characterization of a plasmid-born qepA gene in (ESBL)-producing E. coli clinical isolates were performed. An 2.63% (11/418) were qepA positive isolates, of which a 90.0% carried CTX-M-15 (9/11) and SHV-12 (1/11). All isolates showed chromosomal mutations in the gyrA and parC genes. The clonal groups A, B and C were identified and belonged to, respectively, phylogroups A, B1 and D, as well as the sequence types 205, 405 and 617. Several plasmid profiles were determined with incompatibility groups FIA, FIB and FII. The genetic environment of the qepA in plasmid pEC8020 was different from those reported previously. The plasmid sequence included genes conferring resistance to β-lactams (blaCTX-M-15), macrolides (mphA), fluoroquinolones (qepA1), trimethoprim (dfrB4) and sulphonamides (sul1). Likewise, the IncF-pEC8020 plasmid carried several insertion sequences including ISCR3, IS6100 and multiple copies of IS26. This work contributes to the epidemiology and genetics of plasmid-born qepA genes of ESBL-producing E. coli.

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