The Morphology of Alcaligenes faecalis bacteriophages

Abstract

SUMMARYThe morphology of seven temperate phages from lysogenic strains of Alcaligenes faecalis and two virulent phages obtained from sewage and active on this species was examined by a negative-staining technique. The phages showed a variety of morphological forms and two of them have unusual combinations of features. One (All/A79) has a contractile tail sheath around a hollow core, but lacks the base plate, pins and tail fibres usually associated with this type of tail. The other (A5/A6) resembles the C1, F 1 group of coliphages but has an octahedral head and a collar. The five remaining temperate phages are similar to the C1, F 1 and Providence 9000/9402 group of phages. The sewage phages differ in many respects from one another and also from the temperate phages examined. At least three of the nine phages have octahedral heads.

Genetic transfer and bacterial taxonomy.

“…The taxonomy of Alcaligenes is not well known; some forms may be closer to Vibrio or Moraxella (460,469). From details given in several papers (215,300,301), it seems that the form which shows phage cross-reactions with Proteus and the Providence group has the high GC ratio of 67 to 70%. Moraxella and Neisseria (Fig.…”