Isolation of Acetylene-reducing Spirilla from the Roots of Potamogeton filiformis from Loch Leven (Kinross)

Abstract

Phase-microscopic examination revealed motile spiral-shaped organisms containing many refractile bodies. Enrichment cultures yielded 5 pure cultures of bacteria which consistently reduced acetylene. They appeared to be closely related to Spirillum lipoferum. The absence of other reports of N-fixing spirilla in aquatic systems and temperate climates may be due to the lack of suitable isolation methods.