communities throughout northwestern Siberia and displayed extremely high diversity. Planctomycetota have also been associated with lichen communities and Sphagnum wetlands. Sphagnum wetlands store large amounts of carbon, contributing to the global carbon cycle. Planctomycetota play a considerable role in the degradation of sphagnum, accounting for roughly 15% of the bacterial community. Other bacterial communities Planctomycetota display associations with other bacterial communities, mainly Alphaproteobacteria, Bacteroidota, Gemmatimonadota, and Verrucomicrobiota. The growth of many Planctomycetota is often supported by the essential nutrients provided by other bacteria within the community, and some Planctomycetota rely strongly on symbiotic relationships with other bacteria. Physiology Endocytosis The existence of membrane coat proteins near the intracytoplasmic membrane could be used for an endocytosis-like uptake system, which would be the first instance this function has been found outside of the eukaryotic domain. However, now that the existence of a rigid peptidoglycan cell wall has been confirmed, these vesicles to be able to pass through this cell wall seems unlikely. Additionally, deletion of one of these membrane coat proteins within P. limnophila found no decrease in macromolecule uptake. In addition, with the use of cryoelectron tomography-based three-dimensional reconstruction of Planctomycetota has found that what were originally thought to be vesicles being held in the periplasm are actually just folds in the cytoplasmic membrane. Yet it has been demonstrated that the Planctomycetota can survive on high-molecular-weight polysaccharides as their only source of carbon, meaningthey must have the ability to incorporate complex carbon substrates into their cytoplasm. Three hypotheses have been put forth: First, the Planctomycetota excrete an enzyme which, outside of the cell wall, degrades the complex substrates into smaller monosaccharides, which can more easily be transported through the different membranes. Second, the complex substrates become anchored to the outside of Planctomycetota, which are then able to slowly break down these substrates into oligosaccharides, which are able to be transported into the periplasm of Planctomycetota by specialized proteins. The third hypothesis involves the crateriform structures found on the outside of Planctomycetota cell walls. These structures have fibers lining their pits that may be able to absorb whole polysaccharides into the periplasm, where they would then be digested. Osmotic regulation Almost all bacteria have a cytosol following the outer shape of their peptidoglycan cell wall. Eukaryotes are different in that they have their cytosol divided into multiple compartments to create organelles such as a nucleus. Planctomycetota are unique in that they have