It has been reported that Halobacterium sodomense requires the presence of either starch or bentonite in its growth medium. The present work shows this requirement to be attributable to Bacto-peptone as a component of the medium. When Bacto-peptone is omitted or replaced by other nutrients, no starch is required. Starch (and to a lesser extent bentonite) was shown to effectively protect Halobacterium cells from lysis by Bacto-peptone, and by bile salts, which have been identified as the lytic factor in the peptone.
- Bile salts