This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Liljemark, W. F. Articles by Anderson, D. L. Search for Related Content PubMed PubMed Citation Articles by Liljemark, W. F. Articles by Anderson, D. L.

Morphology and Physiology of the Intracellular Development of Bacillus subtilis Bacteriophage 25

Department of Microbiology and School of Dentistry, University of Minnesota, Minneapolis, Minnesota 55455

ABSTRACT

The morphology of the intracellular development of bacteriophage 25 in Bacillus subtilis 168M has been correlated with nucleic acid synthesis in infected cells. Host deoxyribonucleic acid (DNA) synthesis was shut off by a phage-induced enzyme within 5 min after infection, and another phage-mediated function extensively degraded host DNA at the time of cell lysis. Synthesis of phage DNA in infected cells began within 5 min and continued until late in the rise period. After phage DNA synthesis and coinciding with lysis, much of the unpackaged, newly synthesized phage DNA was degraded. Studies of thin sections of 25 infected cells suggested that unfilled capsids may be precursors to filled capsids in the packaging process. To assess dependence of capsid formation on phage DNA replication, cells were either treated with mitomycin C and infected with normal phage or infected with ultraviolet-irradiated (99% killed) 25. Only empty capsids were found in these cells, indicating that capsid production may be independent of the presence of newly synthesized viral DNA.