Proposal to reclassify Brenneria quercina (Hildebrand and Schroth 1967) Hauben et al. 1999 into a new genus, Lonsdalea gen. nov., as Lonsdalea quercina comb. nov., descriptions of Lonsdalea quercina subsp. quercina comb. nov., Lonsdalea quercina subsp. iberica subsp. nov. and Lonsdalea quercina subsp. britannica subsp. nov., emendation of the description of the genus Brenneria , re

Abstract

Bacterial isolates from oak trees in Spain and Britain, showing symptoms of bark canker and Acute Oak Decline (AOD), respectively, were examined by a polyphasic approach. Both 16S rRNA gene sequencing and multilocus sequence analysis (MLSA), based on partial sequences of gyrB, rpoB, infB and atpD genes, revealed that the isolates were separated into two genetic groups according to their origin. Their closest phylogenetic relative was Brenneria quercina, the causal agent of drippy nut disease of oak, which clustered distant to the other species of the genus Brenneria. MLSA data for species of the genera Brenneria, Pectobacterium, Dickeya, Erwinia, Pantoea and Samsonia confirmed the polyphyletic nature of the genus Brenneria and indicated synonymy of Dickeya dadantii and Dickeya dieffenbachiae. DNA-DNA hybridization experiments confirmed this synonymy and also revealed DNA-DNA relatedness values of 58-73 % between the new oak isolates and B. quercina. Phenotypic and/or chemotaxonomic methods allowed B. quercina and the two genetic groups of new oak isolates to be discriminated from other recognized species of the genus Brenneria and from members of the closely related genera Dickeya, Pectobacterium and Samsonia. Based on the data obtained, the following taxonomic proposals are made: (1)

Phylogeny and classification of Dickeya based on multilocus sequence analysis

“…More recently, the DDH reassociation value of 85±15 % obtained with the type strains of D. dadantii and D. dieffenbachiae resulted in the emendation of the latter species as a subspecies of D. dadantii (Brady et al, 2012). Our MLSA results agree with the DDH values obtained by Brady et al (2012), that the strains formerly classified as D. dieffenbachiae are genetically similar to D. dadantii and, because they have observable phenotypic and genotypic variation, require the infraspecific taxonomic designation. A topology similar to that of the dnaA MP tree was observed with dnaX, albeit with much lower overall bootstrap support ( To establish which gene partitions could be used to produce a phylogeny from concatenated gene sequences, the congruence of the gene partitions was assessed via pairwise ILD tests.…”

Metabarcoding of Bacteria Associated with the Acute Oak Decline Syndrome in England

“…Various gram-negative bacteria of the family Enterobacteriaceae have been associated with AOD symptoms including Gibbsiella quercinecans [31], Lonsdalea quercina ssp. britannica [32], Brenneria goodwinii [33], Gibbsiella greigii [34], a range of species of the genus Rahnella [35], and Brenneria roseae ssp. roseae [36].…”

Dickeya fangzhongdai sp. nov., a plant-pathogenic bacterium isolated from pear trees (Pyrus pyrifolia)

“…The identity of the genus was supported by the analysis of the nucleotide sequences of the chaperone dnaJ (Nhung et al, 2007). Subsequent revision of this group led to the further reclassification of D. dieffenbachiae as a subspecies of D. dadantii (Brady et al, 2012). Recently, isolates from European potatoes were classified in the genus Dickeya (Slawiak et al, 2009), and were considered to represent a novel species, Dickeya solani (van der Wolf et al, 2014).…”