Related Experiment Video
Updated: Aug 19, 2026

Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
Structural proteins of a lipid-containing bacteriophage which replicates in Escherichia coli: phage PR4
Abstract:
PR4 is a lipid-containing bacteriophage which is able to replicate in Escherichia coli. The virus was labeled with either [14C]leucine and [14C]threonine or H235SO4 and then purified by several rounds of sucrose gradient centrifugation. Autoradiographs showed the virus to be composed of six major protein species with molecular weights (1) 68 000, (2) 47 500, (3) 38 500, (4) 35 000, (5) 20 700, (6) 16 500 daltons. Electropherograms showed protein No. 2 to be the major protein, comprising about 43% of the total weight of viral protein.
Related Concept Videos
Lytic Cycle of Bacteriophages
Lysogenic Cycle of Bacteriophages
The Replisome
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
Viral Replication: Lytic Cycle
Viral Replication: Lysogenic Cycle
DNA Bacteriophages

