Vacuum-Drying and Cryopreservation of Prokaryotes

Traditionally, the
ex situ
study of prokaryotes (members of Archaea and Bacteria) has required access to living cultures. Although it may be possibleto maintain a small number of strains by serial transfer, such methods are not the best, particularly for long-term storageor for keeping a large collection. One of the major problems is dealing with the vast range of organisms that have been isolatedto date. Particularly in the case of methods of cultivating prokaryotes, it is almost impossible to give a simple list ofmedia to use. However, general principles are outlined that should cover most of the currently known prokaryotes in pure culture. The methodologies used for the long-term storage of prokaryotes may be divided into those that involve freezing and thosethat involve vacuum-drying. The methods described are those that are either used in the Deutsche Sammlung von Mikroorganismenund Zellkulturen GmbH ( or in other national culture collections.