This species is the nomenclatural type for the genus Pegaeibacterium. Estimated genome sizes for the species range between 2.1 and 2.2 Mb with GC% of 54.27-54.30 %. Some components of the respiratory chain, particularly complex I and V, are encoded by genomes of this species. Cytoplasmic Group A3 [FeFe] and Group 4f [NiFe] hydrogenases are encoded by genomes of this species. As incomplete respiratory pathways are present in this species and no terminal electron acceptors are predicted from the genomes, the presence of a reversible acetyl-CoA synthetase coupled with the Group A3 [FeFe] hydrogenase may be indicative that this species is acetogenic, with respiratory complex I providing oxidized NAD+ and maintaining a proton gradient across the membrane, and complex V (respiratory F-type ATPase) producing ATP. Both assemblies for the species originate from freshwater sediment from Lake Alinen Mustajärvi, Finland. The nomenclatural type for the species is the genome GCA_903820505.1.