The Planctomycetota are a phylum of widely distributed bacteria, occurring in both aquatic and terrestrial habitats. They play a considerable role in global carbon and nitrogen cycles, with many species of this phylum capable of anaerobic ammonium oxidation, also known as anammox. Many Planctomycetota occur in relatively high abundance as biofilms, often associating with other organisms such as macroalgae and marine sponges.
Planctomycetota
Representation of cell division modes in the last PVC common ancestor and in current the PVC superphylum: Outer membranes are represented by thick lines, and inner membranes are represented by thin lines. The peptidoglycan layer is displayed in dotted lines, and FtsZ proteins are displayed as a ring of gray circles.
Transmission electron micrographs of dividing cells displaying different cell division modes in the PVC superphylum. (a) Gemmata obscuriglobus (b) Chthoniobacter flavus (c) Lentisphaera araneosa (d) Phycisphaera mikurensis and (e) Chlamydia trachomatis. Scale bars, 0.5 μm.
Ecklonia radiata, a species of kelp in the phylum Ochrophyta
Anammox, an abbreviation for "anaerobic ammonium oxidation", is a globally important microbial process of the nitrogen cycle that takes place in many natural environments. The bacteria mediating this process were identified in 1999, and were a great surprise for the scientific community. In the anammox reaction, nitrite and ammonium ions are converted directly into diatomic nitrogen and water.
A bioreactor containing the anammox bacterium Kuenenia stuttgartiensis