BCCM/LMG Bacteria Collection, Ghent University, K. L. Ledeganckstraat 35, B-9000 Ghent, Belgium.
Forest Research, Centre for Forestry and Climate Change, Alice Holt Lodge, Farnham, Surrey GU10 4LH, UK.
Int J Syst Evol Microbiol. 2012 Jul;62(Pt 7):1592-1602. doi: 10.1099/ijs.0.035055-0. Epub 2011 Sep 2.
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) reclassification of B. quercina as the type species of a novel genus, Lonsdalea gen. nov., as Lonsdalea quercina comb. nov. (type strain LMG 2724(T)=ATCC 29281(T)=CCUG 48867(T)=CFBP 3617(T)=CIP 105201(T)=DSM 4561(T)=ICMP 1845(T)), (2) classification of the oak isolates as Lonsdalea quercina subsp. iberica subsp. nov. (type strain LMG26264(T)=NCPPB 4490(T)) and Lonsdalea quercina subsp. britannica subsp. nov. (type strain LMG 26267(T)=NCPPB 4481(T)) and leading to the automatic creation of Lonsdalea quercina subsp. quercina subsp. nov. (type strain LMG 2724(T)=ATCC 29281(T)), (3) emendation of the description of the genus Brenneria, and (4) reclassification of Dickeya dieffenbachiae as Dickeya dadantii subsp. dieffenbachiae comb. nov. (type strain LMG 25992(T)=CFBP 2051(T)), with the automatic creation of Dickeya dadantii subsp. dadantii subsp. nov. (type strain LMG 25991(T)=CFBP 1269(T)).
来自西班牙和英国的橡树细菌分离株，分别表现出树皮溃疡和急性橡树衰退（AOD）症状，通过多相方法进行了检查。16S rRNA 基因测序和基于部分 gyrB、rpoB、infB 和 atpD 基因序列的多位点序列分析（MLSA）表明，根据其来源，分离株分为两个遗传群。它们最接近的系统发育相关物是栎树滴脂病菌（Brenneria quercina），这是栎树滴脂病的病原体，与属内的其他物种聚类较远。属内 Brenneria、Pectobacterium、Dickeya、Erwinia、Pantoea 和 Samsonia 物种的 MLSA 数据证实了 Brenneria 属的多系性，并表明 Dickeya dadantii 和 Dickeya dieffenbachiae 同义。DNA-DNA 杂交实验证实了这种同义性，并显示新的橡树分离株与 B. quercina 之间的 DNA-DNA 相关值为 58-73%。表型和/或化学分类方法可将 B. quercina 和两个新的橡树分离株遗传群与属内其他公认的物种以及与密切相关的 Dickeya、Pectobacterium 和 Samsonia 属的成员区分开来。基于获得的数据，提出了以下分类学建议：（1）将 B. quercina 重新分类为一个新属的模式种，Lonsdalea gen. nov.，作为 Lonsdalea quercina comb. nov.（模式株 LMG 2724（T）=ATCC 29281（T）=CCUG 48867（T）=CFBP 3617（T）=CIP 105201（T）=DSM 4561（T）=ICMP 1845（T）），（2）将橡树分离株分类为 Lonsdalea quercina 亚种 iberica 亚种 nov.（模式株 LMG26264（T）=NCPPB 4490（T））和 Lonsdalea quercina 亚种 britannica 亚种 nov.（模式株 LMG 26267（T）=NCPPB 4481（T）），并导致自动创建 Lonsdalea quercina 亚种 quercina 亚种 nov.（模式株 LMG 2724（T）=ATCC 29281（T）），（3）修改 Brenneria 属的描述，（4）Dickeya dieffenbachiae 重新分类为 Dickeya dadantii 亚种 dieffenbachiae comb. nov.（模式株 LMG 25992（T）=CFBP 2051（T）），同时自动创建 Dickeya dadantii 亚种 dadantii 亚种 nov.（模式株 LMG 25991（T）=CFBP 1269（T））。
