Open AccessEffect of pH on the activity of bovicin HC5, a bacteriocin from Streptococcus bovis HC5 1
Author(s) -
Houlihan Adam J,
Mantovani Hilário C,
Russell James B
Publication year - 2004
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1016/s0378-1097(03)00922-4
Subject(s) - potassium , efflux , biology , biophysics , chemistry , biochemistry , organic chemistry
The bacteriocin, bovicin HC5, catalyzed potassium efflux from Streptococcus bovis JB1, and this activity was highly pH dependent. When the pH was near neutral, glucose‐energized cells were not affected by bovicin HC5, but the intracellular steady‐state concentration of potassium decreased at acidic pH values. The idea that pH was affecting bovicin HC5 binding was supported by the observation that acidic pH also enhanced the efflux of potassium from non‐energized cells that had been loaded with potassium. The relationship between bovicin HC5 concentration and potassium depletion was a saturation function, but cooperativity plots indicated that the binding of one bovicin molecule to the cell membrane facilitated the binding of another.