Vibrio cholerae O1 Biotype ElTor bacteriophages AS1-3. Panels A and B show the vibriophage AS1. They are contractile in nature and possess similar pattern as seen in the tail of another O1 ElTor typing vibriophage D10 (Chakrabarti et al., (1993). Panels A and B are shown at the same magnification. Panel C show the vibriophage AS2. The tails are non-contractile in nature. Panels D and E show the vibriophage AS3. Panels D and E are shown at the same magnification. The bars in Panels A, C and D: 50 nm.