Alterations in the cell envelope of Escherichia coli late in bacteriophage T4 infection.

The cell envelope of Escherichia coli was examined for changes during late stages of bacteriophage T4 infection. Late events in T4 infection are shown to result in (i) a reduction in the effectiveness of membrane separation procedures employing either isopycnic sucrose gradient centrifugation or selective solubilization of inner membrane by detergent (Sarkosyl or Triton X-100), (ii) the appearance of a 54 000 dalton host protein in membrane preparations, (iii) the adventitious presence of detergent-resistant phage morphogenetic structures in membrane preparation, and (iv) a decrease in the activity of NADH oxidase and an apparent alteration in its association with inner membrane. These modifications occur regardless of the state of the e and t genes of T4.