Archives of Microbiology

, Volume 124, Issue 2, pp 249–254

Requirement for calcium ions in mycobacteriophage I3 DNA injection and propagation

  • V. Nagaraja
  • K. P. Gopinathan

DOI: 10.1007/BF00427734

Cite this article as:
Nagaraja, V. & Gopinathan, K.P. Arch. Microbiol. (1980) 124: 249. doi:10.1007/BF00427734


Ca2+ ions are absolutely necessary for the propagation of mycobacteriophage I3 in synthetic medium. These ions are required for successful infection of the host and during the entire span of the intracellular development of the phage. A direct assay of the phage DNA injection using 32[P] labelled phage, showns that Ca2+ ions are necessary for the injection process. The injection itself is a slow process and takes 15 min to complete at 37°C. The bacteria infected in presence of Ca2+ tend to abort if the ions are subsequently withdrawn from the growth medium. The effect of calcium withdrawal is maximally felt during the early part of the latent period; however, later supplementation of Ca2+ ions salvage phage production and the mature phage progeny appear after a delayed interval, proportional to the time of addition of Ca2+.

Key words

Calcium ionsPhage propagationPhage DNA injectionMycobacteriophage 13



multiplicity of infection


plaque forming units


ethylene-glycol-bis (β-aminoethyl ether) N,N′-tetraacetic acid

Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • V. Nagaraja
    • 1
  • K. P. Gopinathan
    • 1
  1. 1.Microbiology and Cell Biology LaboratoryIndian Institute of ScienceBangaloreIndia