Bacteriophage proteins associated with the bacterial membrane after bacteriophage T7 infection

Abstract

The majority of the phage-induced proteins made after T7 infection of Escherichia coli are tightly associated with the bacterial membrane. Many of these have been identified. Selective extraction of proteins from these membranes by the detergent Sarkosyl or the chaotropic agent guanidine-hydrochloride indicated that most of these proteins are an integral part of the cytoplasmic membrane and the cell wall. No major changes in the distribution of bacterial proteins in the membrane were observed as a consequence of phage T7 infection.

Protein induced by bacteriophage T4 which is absent in Escherichia coli infected with nuclear disruption-deficient phage mutants

“…Two procedures were tried for subcellular fractionation. The first was procedure 1 of Ennis and Kievitt (12) in which particulate and non-sedimentable fractions of labeled infected cells are prepared in 100 mM phosphate buffer.…”

Alteration of the Escherichia coli membrane by addition of bacteriophage T4 protein synthesized after infection

“…The membranes were incubated for 10 min in an ice bath (G). To another portion of membranes, Sarkosyl, 0.5%, KCl, 40 mM, and potassium-EDTA, 10 mM, pH 7.0 (final concentration) were added, and the suspension was incubated for 30 min at 300C (S). Both membrane suspensions were centrifuged at 20C for 18 h at 100,000 x g. The membranes were washed one time by suspension in 0.0625 M Tris-hydrochloride and centrifuged for 18 h at 100,000 x g. The proteins extracted by guanidine (the supernatant from the first centrifugation and called PG) were dialyzed overnight against 25 mM NH4CO3 and 10 mM 2-mercaptoethanol and then lyophilized.…”

“…Isolation of membranes. Membranes and the soluble proteins of the cell were isolated as previously described (10,17). It was shown in control experiments that, in T4-infected cells, the method was appropriate to cleanly separate membranes from the soluble components of the cell.…”