MORPHOLOGY OF THE SEVEN T-BACTERIOPHAGES

Abstract

The morphology of the seven T-phages has been re-examined by electron microscopy of specimens prepd. by normal air-drying from aqueous suspensions and by freeze-drying. The air-dried material shows evidence of considerable distortion of form, in accord with previous observations, and exhibits dimensions considered to be wholly unreliable. The heads of the frozen-dried phages frequently appear hexagonal in contour, and have a height/width ratio near unity. The dimensions of the frozen-dried particles are believed to be the most reliable obtainable at present. Two types of 3-dimensional shape for the phage heads are considered to be likely: a rhombic dodecahedron, and a hexagonal prism with bipyramidal ends. No choice can be made at this time between these 2 likely forms.