Characterization of Vibriophage VA-1

SUMMARY A bacteriophage isolated from the vaccine strain Vibrio cholerae NIH41 has been characterized by a variety of methods. The phage, called VA-1, is stable at 4 °C, sensitive to temperatures above 20 °C, stable at pH’s between 5 and 10, and more resistant to u.v. irradiation than most coliphages. The velocity constants for adsorption to V. cholerae RV79 and serum neutralization are 5.5 × 10−9 ml/min and 20, respectively. The latent period of VA-1 is about 45 min and its unusually large average burst size is 500 to 600.