Long-term preservation of unstable bacteriophages of enterobacteria

Bacteriophages are integral components of bacterial communities. Their practical applications and significance for humans are various. Thus, keeping phage collections along with their specific host bacteria is an urgent and important mission for biologists. The problems of the long-term storage of phages steel are not completely solved. The main difficulties may occur due to the structural instability of virions as well as an accelerated genetic variability in phage genomes both in vivo and in vitro. In the paper the results of 10-years observation over unstable bacteriophage storage process was presented as well the method of their long-term preservation was proposed. It consisted of the optimization of STMG buffer system (200 mM NaCl, 10 mM Tris-HCl, pH 7.4, 1 mM MgCl, 100 microg/ml gelatin) [Serwer P, Pichler ME. Electrophoresis of bacteroiphage T7 capsids in agarose gels//J. Virol. - 1978 - V28, N3. - P.917-928] by higher gelatin concentration or its replacement by ficoll (2 - 6%), and increasing of Mg(2-) concentration to 10 mM. The proposed buffer composition allowed saving structural entirety of unstable phage virions during their long-term storage.