The complete mitochondrial genome from an unidentified Phalansterium species.

Abstract

We describe the complete sequence and organization of the mitochondrial genome from an unidentified species of Phalansterium. This is the first sequenced mitochondrial genome of a member of Variosea clade(Amoebozoa, Conosa). The sequence was assembled from shotgun reads of DNA from a mixed culture containing the euglenid Monomorphina aenigmatica and an amoebozoan that we demonstrate here is closely related to Phalansterium (in nuclear SSU rRNA phylogenies, it branches between two sequences from described species of Phalansterium).Sequence assembly resulted in two distinct mitochondrial genome types, one fragmented and euglenid-like, and the second a single circular mapping contig of 53,614 bp with an amoebozoan-like set of genes. The Phalansterium sp. mitochondrial genome is gene-rich and densely packed, with a large number of tRNAs and an unusually low ratio of identifiable protein-coding genes to unidentified ORFs. These ORFs potentially encode ribosomal proteins exhibiting a divergent character at the sequence level, and whose identification may be hindered by the presence of RNA editing in Phalansterium mitochondria, as inferred from numerous acceptor stemm is-matches typical of amoebozoan tRNA 5’ editing.