ATR-FTIR Spectroscopy Reveals Bond Formation During Bacterial Adhesion to Iron Oxide

• DOI: 10.1021/la061359p
• Publication Date: 2006-08-29T10:04:50Z
• Authors: Sanjai J. Parikh; Jon Chorover
• Keywords: Phosphodiester bond; Shewanella oneidensis; Phosphonate; Carboxylate; Attenuated total reflection

The contribution of various bacterial surface functional groups to adhesion at hematite and ZnSe surfaces was examined using attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy. When live Shewanella oneidensis, Pseudomonas aeruginosa, Bacillus subtilis cells were introduced a horizontal (α-Fe2O3)-coated internal reflection element (IRE), FTIR peaks emerged corresponding phosphate group binding. These IR not observed when bacteria the uncoated IRE. added colloidal suspensions α-Fe2O3 pH 7, spectra included P−OFe ν(COOH), latter being attributed bridging carboxylate mineral OH groups. Selected model organic compounds with P-containing functionalities (phenylphosphonic acid [PPA], adenosine 5'-monophosphate [AMP], 2'-deoxyadenyl(3'→5')-2'-deoxyadenosine [DADA], deoxyribonucleic [DNA]) produce similar adsorbed α-Fe2O3. data indicate that both terminal phosphate/phosphonate phosphodiester groups, either exuded from cell or present as biomolecules, are involved in Fe-oxides through formation innersphere Fe-phosphate/phosphonate complexes.