Answer to Question #305942 in Biochemistry for tom

Question

Explain how changes in conditions can increase or decrease the population of phage therapy in the human body?

Answer 1

The phage population is generally stable in relation to external factors.

in the case of phage oral injection, stomach acid can have a negative impact on the survival of phage which may lead to treatment failure . The latent period is increased when the phages are incubated at refrigeration temperatures. Bacteriophage can survive at high temperatures (40–90°C) and some phages of Lactococcus can survive pasteurization.

The proliferation of several phages is limited when pH is lower than 4.5, but the risk of pathogenic bacteria food contamination is also generally reduced below pH 4.5.

Also In solid media, the diffusion of bacteriophages could be limited, reducing phage adsorption on bacteria and, consequently, the phage infection capacity. For example, Guenther et al. (2009) have shown that the use of bacteriophages was limited by their diffusion in solid food matrices such as hot dogs, smoked salmon and seafood.

The presence of other compounds could protect bacteria from phages. The phage K is active on numerous strains of S. aureus, but was inactive in raw milk which limits its application in bovine mastitis (Gill et al., 2006a). O’Flaherty et al. (2005) suggested that the immune factors present in raw milk prevented phages from gaining access to bacteria.