Complex history of aerobic respiration and phototrophy in the Chloroflexota class Anaerolineae revealed by high-quality draft genome of Ca. Roseilinea mizusawaensis AA3_104

Abstract

The candidate genus Roseilinea is a novel lineage in the Chloroflexota (formerly Chloroflexi or green nonsulfur bacteria) phylum known so far only from very incomplete metagenome-assembled genomes and preliminary enrichments. Roseilinea is notable for appearing capable of anoxygenic photoheterotrophy despite being only distantly related to well-known phototrophic Chloroflexota in the Chloroflexia class such as Chloroflexus and Roseiflexus. Here, we present a high quality metagenome-assembled genome of a member of Roseilinea, greatly improving our understanding of the metabolic capacity and taxonomic assignment of this genus. These data allow us to confidently describe the genetic basis for photoheterotrophy in these organisms as well as propose a candidate family for these organisms, Ca. Roseilineaceae, within the Anaerolineae class of Chloroflexota.