Effects of Supplemental Calcium or Calcium-binding Agents on Staphylococcal Bacteriophage Proliferation in Skim Milk1

Abstract

Additions of 0.0005 N calcium borogluconate to Trypticase Soy Broth (TSB) produced an increase in phage titer about 1 million-fold, whereas its addition to skim milk resulted in about a 100-fold decrease in the maximal titer. Supplemental calcium had a stimulatory influence on bacterial growth in TSB but not in skim milk. Studies were made of the effect of binding of calcium of skim milk on the proliferation of staphylococcal bacteriophage. Sequestering the calcium with 2% phosphate mixture inactivated the phages without affecting the bacterial growth. However, chelation of calcium by 0.012% ethylenediaminetetraacetic acid produced an inhibitory effect on both the phages and the bacteria.

Lysogeny inLactobacillus delbrueckiistrains and characterization of two new temperate prolate-headed bacteriophages

“…The role of inorganic cations (Ca 2+ and Mg 2+ ) in cell lysis is noteworthy. It was observed that chelating agents are able to inhibit bacteriophage proliferation by binding divalent cations (Shafia and Thompson 1964; Das and Marshal 1967; Sadashiva Karnik and Gopinathan 1980; Hicks and Surjawan 2002; Suárez et al. 2007), interfering with phage adsorption (Lorenz et al.…”