Publications

4839

Summary The bacterial tree contains many deep‐rooting clades without any cultured representatives. One such clade is ‘ E ndomicrobia’, a class‐level lineage in the phylum E lusimicrobia represented so far only by intracellular symbionts of termite gut flagellates. Here, we report the isolation and characterization of the first free‐living member of this clade from sterile‐filtered gut homogenate of defaunated (starch‐fed) R eticulitermes santonensis . Strain R sa215 is a strictly anaerobic ultramicrobacterium that grows exclusively on glucose, which is fermented to lactate, acetate, hydrogen and CO 2 . Ultrastructural analysis revealed a G ram‐negative cell envelope and a peculiar cell cycle. The genome contains a single set of nif genes that encode homologues of G roup IV nitrogenases, which were so far considered to have functions other than nitrogen fixation. We documented nitrogenase activity and diazotrophic growth by measuring acetylene reduction activity and 15 N 2 incorporation into cell mass, and demonstrated that transcription of nifH and nitrogenase activity occur only in the absence of ammonium. Based on the ancestral relationship to ‘ C andidatus   E ndomicrobium trichonymphae’ and other obligate endosymbionts, we propose the name ‘ E ndomicrobium proavitum ’ gen. nov., sp. nov. for the first isolate of this lineage and the name ‘ E ndomicrobia ’ class. nov. for the entire clade.

ABSTRACT The draft genome sequence of “ Candidatus Liberibacter asiaticus” strain SGCA5 from an orange citrus tree in San Gabriel, California, is reported here. SGCA5 has a genome size of 1,201,445 bp, a G+C content of 36.4%, 1,152 predicted open reading frames (ORFs), and 42 RNA genes.

ABSTRACT Here we present the draft genome of a distantly related member within the phylum Bacteriodetes , “ Candidatus Bacteroides periocalifornicus .” The draft genome sequence was assembled with metagenomic data from a patient with periodontitis. The closest relative has less than 68% average nucleic identity, supporting a novel family within Bacteriodetes .

ABSTRACT The genome of “ Candidatus Profftella armatura” strain YCPA from Diaphorina citri in Guangdong, China, was sequenced. The strain has a chromosome of 457,565 bp, 24.3% G+C content, 364 predicted open reading frames (ORFs), and 38 RNAs, and a plasmid, pYCPA54, of 5,458 bp with 23.9% G+C content and 5 ORFs.