Conditioning film and initial biofilm formation on electrochemical CaCO₃ deposition on a metallic net in the marine environment

Abstract

Electrochemical deposition of minerals is a unique technology for artificial reef constructions, relying on calcium carbonate (CaCO₃) build-up over metallic structures through electrolysis of seawater. The present study traces the first 72 h following electric current termination on bacterial biofilm build-up on a metallic net covered with CaCO₃. 16S rRNA clone libraries indicated a dynamic succession. Proteobacteria and Bacteroidetes were evident at all sampling times while Cyanobacteria appeared only within the first 8 h. A significant increase in total organic carbon (TOC) and total protein was observed after 48 h with a significant correlation (R ² = 0.74), indicating TOC is a good tool for characterizing initial biofilm formation. 18S rRNA gene sequences obtained 72 h following current termination indicated a significant presence of Cnidarians (51%). Understanding the dynamics among primary bacterial settlers is important because they play a crucial role in driving the colonization of sessile invertebrate communities on artificial, as well as natural surfaces.

Keywords:

• bacteria
• biofilm
• CaCO₃
• conditioning film
• early colonizers
• electrochemical deposition

Acknowledgements

This work was supported by ISF grant 1169/07, and a Levi-Eshkol scholarship to N. Siboni from the Israeli Ministry of Science, Culture and Sports.

Additional information

Notes on contributors

Ariel Kushmaro

The first two authors contributed equally to this article.