Liberibacter crescens gen. nov., sp. nov., the first cultured member of the genus Liberibacter

Jennie R. Fagen, Michael T. Leonard, Janelle F. Coyle, Connor M. McCullough, Austin G. Davis-Richardson, Michael J. Davis, Eric W. Triplett

¹Microbiology and Cell Science Department, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, USA

²Plant Pathology Department, Citrus Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, Lake Alfred, FL, USA

Correspondence
Eric W. Triplett ewt{at}ufl.edu

International Journal of Systematic and Evolutionary Microbiology 2014; 64(Pt 7):2461–2466 · https://doi.org/10.1099/ijs.0.063255-0

Abstract

The Gram-stain-negative, rod-shaped bacterial isolate BT-1^T is the closest relative to the genus ‘Candidatus Liberibacter’ cultured to date. BT-1^T was recovered from the phloem sap of a defoliating mountain papaya in Puerto Rico. The BT-1^T 16S rRNA gene sequence showed that strain BT-1^T is most closely related to members of the genus ‘Ca. Liberibacter’ sharing 94.7 % 16S rRNA gene sequence similarity with ‘Ca. Liberibacter americanus’ and ‘Ca. Liberibacter asiaticus’. Additionally, average nucleotide identity, 16S rRNA gene sequences and conserved protein sequences supported inclusion of the previously described species of the genus ‘Ca. Liberibacter’ in a genus with BT-1^T. The prominent fatty acids of isolate BT-1^T were C_18 : 1ω7c (77.2 %), C_16 : 0 OH (4.8 %), C_18 : 0 (4.4 %) and C_16 : 0 (3.5 %). Both physiological and genomic characteristics support the creation of the genus Liberibacter, as well as the novel species Liberibacter crescens gen. nov., sp. nov. with type strain BT-1^T ( = ATCC BAA-2481^T = DSM 26877^T).