The role of energy‐yielding ATPase and respiratory chain at early stages of bacteriophage T4 infection

Recently a chemiosmotic mechanism of DNA transport has been formulated [ 11, according to which the entry of phage DNA is considered to be dependent on the energy-yielding activity of ATPase and the respiratory chain.Here we report an experimental ex~ination of the role of ATPase and the respiratory chain in the early stages of bacteriophage infection. '2. Materials and methods Escherichia coli K12 AN 180 (F-, arg-, thi-, mtl-, xyl-, SW) and an isogenic strain AN 120 (WC A 401) were generous gifts of Professor F. Gibson (Australian National University).Stock suspension of wild-type bacte~oph~e T4 containing 10" infectious p~ticles/~ salt solution was obtained from Dr R. Nivinskas (Institute of Biochemistry, Vilnius).The salt solution contained 7 g Na2HP04, 3 g KH2P04, 5 g NaCl, 1 mm01 MgCl, and 0.1 mmol CaClz in 1 liter distilled water.Before each experiment the stock solution of bacteriophage T4 was diluted 40.fold with medium I @H 7.0) containing 75 mM KH2P0,, 1 mM MgS04, 0.1 mM CaCl*, 0.4% glucose and L-tryptophan (50 pg/ml).E. coli was grown up to 3-5 X 10' cells/ml in a gyratory shaker (250 rev./min) at 37°C containing liquid medium 9