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PubMed · 9920412

Calcium signalling in Bacillus subtilis.

M L Herbaud·A Guiseppi·F Denizot·J Haiech·M C Kilhoffer
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Abstract

Few systematic studies have been devoted to investigating the role of Ca2+ as an intracellular messenger in prokaryotes. Here we report an investigation on the potential involvement of Ca2+ in signalling in Bacillus subtilis, a Gram-positive bacterium. Using aequorin, it is shown that B. subtilis cells tightly regulate intracellular Ca2+ levels. This homeostasis can be changed by an external stimulus such as hydrogen peroxide, pointing to a relationship between oxidative stress and Ca2+ signalling. Also, B. subtilis growth appears to be intimately linked to the presence of Ca2+, as normal growth can be immediately restored by adding Ca2+ to an almost non-growing culture in EGTA containing Luria broth medium. Addition of Fe2+ or Mn2+ also restores growth, but with 5-6 h delay, whereas Mg2+ did not have any effect. In addition, the expression of alkyl hydroperoxide reductase C (AhpC), which is strongly enhanced in bacteria grown in the presence of EGTA, also appears to be regulated by Ca2+. Finally, using 45Ca2+ overlay on membrane electrotransferred two-dimensional gels of B. subtilis, four putative Ca2+ binding proteins were found, including AhpC. Our results provide strong evidence for a regulatory role for Ca2+ in bacterial cells.

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Amino Acid SequenceBacillus subtilisCalciumCalcium SignalingCalcium-Binding ProteinsEgtazic AcidHomeostasisMolecular Sequence DataJournal ArticleResearch Support, Non-U.S. Gov't

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M L Herbaud, A Guiseppi, F Denizot, J Haiech, M C Kilhoffer. 1998-12-10. Calcium signalling in Bacillus subtilis.. https://doi.org/10.1016/s0167-4889(98)00145-1

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