Bacteriophage T4 Development Depends on the Physiology of its Host Escherichia Coli

Abstract

Several parameters of phage T4 adsorption to and growth in Escherichia coli B/r were determined. All changed monotonously with the bacterial growth rate (p), which was modified by nutritional conditions. Adsorption rate was faster at higher p values, positively correlated to cell size, and increased by pretreatment with low penicillin (Pn) concentrations; it was directly proportional to total cellular surface area, indicating a constant density of 14 receptors on cell envelopes irrespective of growth conditions. Parameters of phage development and cell lysis were pdependent. The rate of phage release and burst size increased, while the eclipse and latent periods decreased with increasing p. Differentiation between the contribution of several physiological parameters to the development of 14 was performed by manipulating the host cells. A competitive inhibitor of glucose uptake, methyl a-o-glucoside, was exploited to reduce the growth rate in the same effective carbon source. Synchronous cells were obtained by the 'baby-machine' and large cells were obtained by pretreatment with low Pn concentrations. Lysis was delayed by superinfection, and DNA content and concentration were modified by growing a thy mutant in limiting thymine concentrations. The results indicate that burst size is not limited by cell size or DNA composition, nor directly by the rate of metabolism, but rather by the rates of synthesis and assembly of phage components and by lysis time. The rates of synthesis and assembly of phage components seem to depend on the content of the protein-synthesizing system and lysis time seems to depend on cellular dimensions.

Variation in cell volume and community composition of bacteria in response to temperature

“…Because viruses are usually species-or strain-specific (Børsheim 1993), they might influence the bacterial community composition by controlling the abundant species or strains. It has been shown that prokaryotic heterotrophic production increases with increasing temperature up to ~15°C (Apple et al 2006), and as growth rate increases, the length of the lytic cycle decreases and burst-size increases, leading to higher rates of virus production (Proctor et al 1993, Hadas et al 1997. Using phage isolates, it has been demonstrated that the injection of phage DNA is temperature dependent, which may be related to the optimal growth temperature of the host (Giladi et al 1995).…”

The kinetics of <i>Escherichia coli</i> B growth and bacteriophage T4 multiplication in SM-1 novel minimal culture medium

“…It allowed us to obtain high titers of phage (1.2 × 10 16 pfu/ml), which indicated that the new medium is optimal for T4 multiplication. Hadas et al (1997) investigated supplementation of different carbon and nitrogen sources to an M9 minimal medium and its impact on the rate of T4 phage synthesis in E. coli B/r. Surprisingly, the highest titer of phage multiplication was obtained not using an LB medium with glucose, but an M9 minimal medium supplemented with casein hydrolysate and glucose.…”

“…Situations requiring the removal of these components during purification may increase the time, or stop the registration process, of the potential medical preparations. In addition, yeast extract, as a component of a medium, seems to show an inhibitory effect relative to the rate of phage multiplication (Hadas et al, 1997).…”

Inorganic polyphosphate essential for lytic growth of phages P1 and fd

“…The procedure was based on that of Hadas et al (41). Cultures were grown in LB broth to exponential phase (OD 540 Ϸ0.3) as described above.…”