Characterization of a Thermophilic Bacteriophage for Bacillus stearothermophilus

Abstract
The biological and physical-chemical properties of the thermophilic bacteriophage TP-84 were investigated. TP-84 was shown to be lytic for 3 of 24 strains of Bacillus stearothermophilus tested over the temperature range of 43 to 76 C. The latent period of TP-84 on B. stearothermophilus strain 10 was 22 to 24 min. TP-84 has a hexagonal head, 53 m[mu] in diameter and 30 m[mu] on a side; its tail is 130 m[mu] long and 3 to 5 m[mu] wide. The phage has an S20, W of 436, and bands at a density of 1.508 g/cc in CsCl (pH 8.5). The diffusion coefficient of TP-84 was calculated to be 6.19 x 10-8 cm2/sec. From the sedimentation and diffusion data, a particle molecular weight of 50 million daltons was calculated for TP-84. The phage DNA has a base composition of 42% guanine + cytosine, deduced from buoyant density and melting temperature measurements.