Biofilm development in the extremely acidophilic archaeon ‘Ferroplasma acidarmanus’ Fer1
- 560 Downloads
‘Ferroplasma acidarmanus’ Fer1 is an iron-oxidizing extreme acidophile isolated from the Iron Mountain mine, California, USA. This archaeon is predominantly found in biofilm-associated structures in the environment, and produces two distinct biofilm morphologies. Bioinformatic analysis of the ‘F. acidarmanus’ Fer1 genome identified genes annotated as involved in attachment and biofilm formation. No putative quorum sensing signaling genes were identified and no N-acyl homoserine lactone-like compounds were found in ‘F. acidarmanus’ Fer1 biofilm supernatant. Scanning confocal microscopy analysis of biofilm development on the surface of pyrite demonstrated the temporal and spatial development of biofilm growth. Furthermore, two-dimensional polyacrylamide gel electrophoresis was used to examine differential protein expression patterns between biofilm and planktonic populations. Ten up-regulated proteins were identified that included six enzymes associated with anaerobic growth, suggesting that the dominating phenotype in the mature biofilm was associated with anaerobic modes of growth. This report increases our knowledge of the genetic and proteomic basis of biofilm formation in an extreme acidophilic archaeon.
KeywordsFerroplasma Archaea Acidophile Biofilm Confocal microscopy
Extracellular polymeric substances
N-acyl homoserine lactones
Mineral salts medium
2-Dimensional polyacrylamide gel electrophoresis
Matrix-assisted laser desorption ionization time-of-flight
Drs. Jillian F. Banfield and Katrina J. Edwards are gratefully acknowledged for provision of ‘F. acidarmanus’ Fer1 and helpful discussions. Polished pyrite chips were kindly prepared by Åke Sandström. The technical assistance of Martina Maidment and Lynda Flegg was greatly appreciated and Dr. Paul Thomas is acknowledged for assistance with the confocal microscopy. Trypsin digests and MALDI-TOF analysis of excised protein spots was carried out at the John Innes Centre, Norwich. This work was funded by a BBSRC Research grant and the John and Pamela Salter Charitable Trust.
- Fu JH, Hu YH, Qiu GZ, Liu JS, Xu J (2004) Biofilm forming and leaching mechanism during bioleaching chalcopyrite by Thiobacillus ferrooxidans. Trans Nonferr Metals Soc China 14:383–387Google Scholar