Sphaerocystis

Sphaerocystis is a genus of unicellular, spherical bacteria belonging to the order Phycisphaerales. These bacteria are typically found in freshwater environments, including lakes and ponds, and are often associated with phytoplankton blooms. They are characterized by their spherical shape, which gives them their name (from the Greek "sphaira" meaning sphere). Sphaerocystis are gram-negative and motile, possessing a single polar flagellum. Their cell wall structure is complex, and they lack a true nucleus, classifying them as prokaryotes.

Reproduction in Sphaerocystis occurs asexually through binary fission. Under favorable conditions, they can proliferate rapidly, sometimes forming large colonies or contributing to the visible coloration of water bodies. While generally considered non-pathogenic, their abundance can impact water quality by consuming dissolved oxygen during decomposition. Research into Sphaerocystis is ongoing, with efforts focused on understanding their ecological roles, their interactions with other microorganisms, and their potential contribution to biogeochemical cycles within aquatic ecosystems. Their specific metabolic pathways and genetic makeup are areas of active investigation.