Multilocus Variable-Number-Tandem-Repeats Analysis (MLVA) distinguishes a clonal complex of Clavibacter michiganensis subsp. michiganensis strains isolated from recent outbreaks of bacterial wilt and canker in Belgium

Two clusters of invasive meningococcal disease in the north of Italy both due to serogroup C/ST-11 clonal complex are here described. The objective of the investigation was to analyse the phenotype and the genotype of meningococci involved in the two clusters which were of national relevance due to the fatal outcome of the majority of cases (six of the total of 10 cases). All the strains were C:2a:P1.5 ST-11/ET-37 clonal complex. Two pulsed field gel electrophoresis (PFGE) and variable number tandem repeats (VNTR) profiles were identified, one for each cluster. VNTRs were different from those detected in Italy for C/ST-11 strains isolated from sporadic cases in the same period. This laboratory surveillance report highlights the importance and the crucial role of molecular characterisation to confirm the relatedness among meningococci responsible for clusters of cases.

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Response of tomato (Solanum lycopersicum) varieties to Clavibacter michiganensis subsp. michiganensis infection

Revista Mexicana de Fitopatología Mexican Journal of Phytopathology ◽

10.18781/r.mex.fit.2106-8 ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Luis Martín Rivera-Sosa ◽

Gustavo Ramírez-Valverde ◽

Beatriz Martínez-Yáñez ◽

Alfonsina Judith-Hernández ◽

Sergio Aranda-Ocampo

Keyword(s):

Solanum Lycopersicum ◽

Bacterial Wilt ◽

Clavibacter Michiganensis ◽

Phenological Stages ◽

Tomato Plants ◽

Canker Disease ◽

Clavibacter Michiganensis Subsp ◽

Bacterial Wilt And Canker ◽

Das Elisa

Clavibacter michiganensis subsp. michiganensis causes bacterial wilt and canker disease of tomato. The objectives of this research were i) to characterize and identify the most aggressive Cmm in Chignahuapan, Puebla, ii) to evaluate the tolerance in two phenological stages of 10 tomato varieties to infection by CP_Cmm1 in the greenhouse and the in vitro sensitivity of the bacteria to bactericides. 12 Cmm isolates were collected from tomato plants and a strain (CP_Cmm-1) with greater aggressiveness was selected according to the time of manifestation of symptoms in plants of var. Reserva. Afterward, the strain was inoculated by cutting with scissors embedded in a suspension with 3 x 108 UFC mL-1 in two phenological stages (at five and 10 true leaves). Symptoms were evaluated for 30 days after inoculation. Additionally, the sensitivity of CP_Cmm-1 to eight commercial bactericides in vitro was evaluated. The results showed that the CP_Cmm-1 strain was identified with 97% similarity with the API20 E system, positive with DAS-ELISA, and by PCR it showed 96.6% identity with Clavibacter michiganensis subsp. michiganensis. The Saher variety showed greater tolerance to infection (* = p?0.05) both in the stage of five and 10 leaves; the varieties Sv4401, Nápoles, and Súper óptimo showed greater susceptibility in the five-leaf stage. The Sv4401 variety was highly susceptible in both stages. Neither variety was resistant to infection by CP_Cmm-1. The use of the Sahel variety and kasugamycin could reduce the damage of this bacteria.

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Virulence and pCM1 plasmid carriage are related to BOX‐PCR fingerprint type in strains of Clavibacter michiganensis subsp. michiganensis that cause bacterial wilt and canker of tomato in Argentina

Plant Pathology ◽

10.1111/ppa.13163 ◽

2020 ◽

Vol 69 (4) ◽

pp. 723-732

Author(s):

Eliana Wassermann ◽

Marcela S. Montecchia ◽

Valeria S. Garaventa ◽

Olga S. Correa ◽

Ana M. Romero

Keyword(s):

Bacterial Wilt ◽

Clavibacter Michiganensis ◽

Clavibacter Michiganensis Subsp ◽

Plasmid Carriage ◽

Bacterial Wilt And Canker

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Molecular characteristics of Brucella melitensis isolates from humans in Qinghai Province, China

Infectious Diseases of Poverty ◽

10.1186/s40249-021-00829-0 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Zhi-Jun Zhao ◽

Ji-Quan Li ◽

Li Ma ◽

Hong-Mei Xue ◽

Xu-Xin Yang ◽

...

Keyword(s):

Tandem Repeats ◽

Brucella Melitensis ◽

Draft Genome ◽

Geographic Origin ◽

Variable Number ◽

Human Brucellosis ◽

Molecular Characteristics ◽

Whole Genome ◽

Qinghai Province ◽

Variable Number Tandem Repeats

Abstract Background The prevalence of human brucellosis in Qinghai Province of China has been increasing rapidly, with confirmed cases distributed across 31 counties. However, the epidemiology of brucellosis transmission has not been fully elucidated. To characterize the infecting strains isolated from humans, multiple-locus variable-number tandem repeats analysis (MLVA) and whole-genome single-nucleotide polymorphism (SNP)-based approaches were employed. Methods Strains were isolated from two males blood cultures that were confirmed Brucella melitensis positive following biotyping and MLVA. Genomic DNA was extracted from these two strains, and whole-genome sequencing was performed. Next, SNP-based phylogenetic analysis was performed to compare the two strains to 94 B. melitensis strains (complete genome and draft genome) retrieved from online databases. Results The two Brucella isolates were identified as B. melitensis biovar 3 (QH2019001 and QH2019005) following conventional biotyping and were found to have differences in their variable number tandem repeats (VNTRs) using MLVA-16. Phylogenetic examination assigned the 96 strains to five genotype groups, with QH2019001 and QH2019005 assigned to the same group, but different subgroups. Moreover, the QH2019005 strain was assigned to a new subgenotype, IIj, within genotype II. These findings were then combined to determine the geographic origin of the two Brucella strains. Conclusions Utilizing a whole-genome SNP-based approach enabled differences between the two B. melitensis strains to be more clearly resolved, and facilitated the elucidation of their different evolutionary histories. This approach also revealed that QH2019005 is a member of a new subgenotype (IIj) with an ancient origin in the eastern Mediterranean Sea.

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Slipped-Strand Mispairing at Noncontiguous Repeats in Poecilia reticulata: A Model for Minisatellite Birth

Genetics ◽

10.1093/genetics/155.3.1313 ◽

2000 ◽

Vol 155 (3) ◽

pp. 1313-1320 ◽

Cited By ~ 2

Author(s):

John S Taylor ◽

Felix Breden

Keyword(s):

Tandem Repeat ◽

Poecilia Reticulata ◽

Tandem Repeats ◽

Phylogenetic Reconstruction ◽

Variable Number ◽

Repeat Motif ◽

Raw Material ◽

Direct Repeats ◽

Mt Dna ◽

Variable Number Tandem Repeats

Abstract The standard slipped-strand mispairing (SSM) model for the formation of variable number tandem repeats (VNTRs) proposes that a few tandem repeats, produced by chance mutations, provide the “raw material” for VNTR expansion. However, this model is unlikely to explain the formation of VNTRs with long motifs (e.g., minisatellites), because the likelihood of a tandem repeat forming by chance decreases rapidly as the length of the repeat motif increases. Phylogenetic reconstruction of the birth of a mitochondrial (mt) DNA minisatellite in guppies suggests that VNTRs with long motifs can form as a consequence of SSM at noncontiguous repeats. VNTRs formed in this manner have motifs longer than the noncontiguous repeat originally formed by chance and are flanked by one unit of the original, noncontiguous repeat. SSM at noncontiguous repeats can therefore explain the birth of VNTRs with long motifs and the “imperfect” or “short direct” repeats frequently observed adjacent to both mtDNA and nuclear VNTRs.

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