Figure 1.

Phylogenetic tree highlighting the position of P. arcticus relative to the type strains of the other species within the genus Phaeobacter and neighboring genera such as Leisingera. The tree was inferred from 1,385 aligned characters [6,7] of the 16S rRNA gene sequence under the maximum likelihood (ML) criterion [8]. Oceanicola species were included in the dataset as outgroup taxa. The branches are scaled in terms of the expected number of substitutions per site. Numbers adjacent to the branches are support values from 1,000 ML bootstrap replicates [9] (left) and from 1,000 maximum-parsimony bootstrap replicates [10] (right) if larger than 60%. Lineages with type-strain genome sequencing projects registered in GOLD [11] are labeled with one asterisk, those also listed as ‘Complete and Published’ with two asterisks [12]. Two novel genome sequences were published in this issue [58,59].