Dr Susanne Gebhard / Dr Kevin Paine / Dr Michael Harbottle / Prof Andrew Heath / Dr Bianca Reeksting / Dr Magdalini Theodoridou




The choice of bacteria for any specific application will depend on the anticipated exposure conditions (e.g. temperature and salinity). To‐date many of these attributes have received limited attention with the focus being on optimum conditions for alkaliphilic bacterial species. However, the onset and progression of carbonation reduces the pH of the cover zone to the extent that the pH in the vicinity of a crack may well be below. Furthermore, much of the work to date has used bacteria that grow well in laboratory conditions (e.g. >25 °C). In practice self‐healing is likely to be required in much cooler conditions and in the presence of chloride salts. To address
these challenges, there is a need to isolate bacteria that grow over a wider range of conditions or employ multi‐bacteria systems.

  • Task 1 – research needed to isolate spore‐forming, aerobic bacteria (i.e. Bacillus species) from environmental samples where cool and/or high‐salt conditions predominate such as material from limestone caves (7 to 9 °C) or marine sediments from limestone areas
  • Task 2 – characterisation for the quantity of calcite produced and their growth under the range of stressful conditions that are of interest (cold, alkaline, high salinity).
  • Task 3 – choose the genes required for efficient calcite precipitation
  • Task 4 – testing the functionality of the synthetic calcite precipitation modules at different pH levels, temperatures etc.

Crack in mortar healed by bacterial activity