[The survival of D-29 and MyF2 P/59-mycobacteriophages in continuous cultures]

The cultivation technique of two mycobacteriophages (D-29 and MyF2 P/59) in continuous cultures with a simple synthetic medium is described. The ATCC-607-strain (M. smegmatis) was used as a host strain. The medium was exchanged every 24 hours for 14 days, then the whole cultivation equipment including waste bottle was hermetically closed and preserved in a thermostat for seven years. Every six months about 250 ml of new liquid medium was added into the cultivation container after finishing the passage cultivation. Both mycobacteriophages could be found out still after 6 years in the mixture of the mycobacteriophages preserved in the waste bottle and in the culture container even after seven years. The possibility of using the technique of continuous cultivation of phages for preparing fresh 24 hours old suspensions necessary for phage typing of the mycobacteria is discussed.