Morphogenesis of bacteriophage phi 29 of Bacillus subtilis: prohead restoration for DNA-gp3 packaging and assembly.
The DNA-protein complex DNA-gp3 of phi 29 is efficiently packaged into purified proheads with the aid of plasmid-derived gp16. The filled heads can be assembled to phage by addition of an extract providing the products for neck-tail assembly (Bjornsti et al., J. Virol. 50:766-772, 1984). However, purified proheads lost their competence to package DNA-gp3 upon storage for 2 months at 4 degrees C. Competence was restored by complementation with extracts of certain mutant-infected cells, and these experiments demonstrated that late proteins were not involved; restoration obtained with 4-8-14--infected cells was indistinguishable from that obtained with 7-8-14--infected cells. 2-8-14- and 3-8-14- extracts restored about one-third of the capacity to package exogenous DNA-gp3. A 1-8-14- extracts restored activity to package 20.6% of the DNA-gp3 added, but phage were not produced.
D001412:Bacillus subtilis; D001435:Bacteriophages / Q000235:genetics*; D004279:DNA, Viral / Q000032:analysis*; D003850:Deoxyribonuclease I / Q000494:pharmacology; D005814:Genes, Viral; D006023:Glycoproteins / Q000032:analysis*; D009024:Morphogenesis; D014764:Viral Proteins / Q000032:analysis*
D004279:DNA, Viral; D006023:Glycoproteins; D014764:Viral Proteins; D003850:Deoxyribonuclease I