Poribacteria are Gram-negative primarily aerobic mixotrophs with the ability for oxidative phosphorylation, glycolysis, and autotrophic carbon fixation via the Wood – Ljungdahl pathway.

Further, Poribacteria seem to engage in assimilatory denitrification and ammonia scavenging with potential relevance in nitrogen re-cycling within the sponge holobiont.

Poribacteria were previously thought to be distinguished from other microorganisms associated with marine sponges by such a distinctive morphology featuring a large membrane-bound cellular compartment that was suggested to contain DNA.

[6] More recently, correlative light-electron microscopy, confirmed two elements of poribacterial subcellular compartmentation:[7] Firstly, Bacterial microcompartments, atypically localized at the cell membrane.

[6] In addition, genetic infrastructure for sterol biosynthesis is observed in poribacterial genomes, otherwise found almost exclusively in eukaryotes and the planctomycete Gemmata obscuriglobus.