P22-
hybrids which retain the protein coat of P22 have been isolated and characterized into two types. Type 1 hybrids which have the
c through O-P genes of
are unable to grow lytically on
Salmonella typhimurium. On the other hand, type 2 hybrids which contain only the
c region of
, plated on
S. typhimurium. Both hybrid types retained the generalized transducing and antigenic conversion capabilities of P22.
Communicated by T. Yura