The Morphology of Proteus Bacteriophages

Abstract

The morphology of 28 bacteriophages active on members of the Proteus-Providence group of organisms was examined by a negative staining technique. Examples of the "T-even", T3 and P22 morphologies were encountered as well as phages with non-contractile cross-striated tails resembling a group of coliphages. Others resembled staphylococcal and pseudomonas phages, Two phages (9, 7479) with octahedral capsids were encountered. A temperate Proteus mirabilis phage (12/57) and a temperate P. morganii phage (10041/2815) differ from phase P22 in that they possess collars. A P. rettgeri phage (7480 b) is unique in that it possesses a head with a regular hexagonal outline, a collar and non-contractile tail while a Providence phage (9266) is believed to be the largest phage active on Gram-negative bacteria.