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Method for Growth and Purification of Bacteriophage 643 on Streptococcus lactis ML3

D J Lyttle1, G B Petersen

  • 1Department of Biochemistry, University of Otago, Dunedin, New Zealand.

Applied and Environmental Microbiology
|July 1, 1984
PubMed

Insights

Bacteriophage 643 yield was significantly enhanced by infecting Streptococcus lactis ML3 cultures and transferring them to fresh medium. This method resulted in high bacteriophage titers after cell lysis and subsequent purification.

Area of Science:

  • Microbiology
  • Virology
  • Molecular Biology

Background:

  • Bacteriophages are viruses that infect bacteria.
  • Streptococcus lactis ML3 is a bacterium used in dairy fermentation.
  • Optimizing bacteriophage production is crucial for research and industrial applications.

Purpose of the Study:

  • To develop an improved method for increasing the yield of bacteriophage 643.
  • To optimize the conditions for bacteriophage production from Streptococcus lactis ML3.

Main Methods:

  • Infecting Streptococcus lactis ML3 cultures in late-log phase with bacteriophage 643.
  • Harvesting infected cells and resuspending them in fresh, phosphate-buffered minimal medium.
  • Lysing cells to release bacteriophages, followed by purification using 2 M NaCl, differential centrifugation, and CsCl density gradient centrifugation.

Main Results:

  • The described method significantly increased the yield of bacteriophage 643.
  • High titers of bacteriophage were obtained after the optimized lysis and purification process.
  • Phage particles were successfully dissociated from cellular debris and purified.

Conclusions:

  • This optimized protocol provides an effective strategy for enhancing bacteriophage 643 production.
  • The method is suitable for generating high yields of purified bacteriophage for further studies.

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