Cell-free nitrogenase and hydrogenase from actinorhizal root nodules

Field-grown alder (Alnus glutinosa) root nodules were disrupted in liquid nitrogen to release the actinomycete endophytes. The endophytes were broken by mild sonic oscillation and yielded a cell-free nitrogenase preparation capable of reducing acetylene and protons. In addition, the preparation carried a cell-free uptake hydrogenase.