Influence of H+ and Calcium Ions on Surface Functional Groups of Synechococcus PCC 7942 Cells
- 10 May 2006
- journal article
- research article
- Published by American Chemical Society (ACS) in Langmuir
- Vol. 22 (12), 5435-5442
- https://doi.org/10.1021/la0531143
Abstract
The chemistry of the surface functional groups of picocyanobacteria SynechococcusPCC 7942 cells was examined as a function of H+ and calcium concentrations. Titration experiments, infrared spectroscopy, biosorption experiments, and chemical modeling were used to gain insight into the mechanisms of biosorption. The pKa and concentration of active sites on the cell wall were clarified with the aid of potentiometric titration. Modeling calculations and infrared spectra are consistent with pKa's values of 4.3, 5.2, 6.9, 9.1, and 10.0 and a total concentration of 7.8 10-4 mol g-1. Spectral analysis of an aqueous cellular suspension revealed a presence of carboxyl, amide, phosphate, hydroxyl, and carbohydrate moieties. Correspondence between spectral data and potentiometric titration curves supported the hypothesis that carboxylate groups and phosphodiester groups mediate calcium adsorption to bacterial cells. This process is strongly pH dependent. In the second part of the experimental work, Synechococcuscells were suspended in the presence of different calcium concentrations. Mechanistic modeling demonstrated that the calcium adsorption phenomenon can be described taking into account only two mechanisms: ion exchange and complexation.Keywords
This publication has 27 references indexed in Scilit:
- FTIR Spectroscopic Study of Biogenic Mn-Oxide Formation byPseudomonas putidaGB-1Geomicrobiology Journal, 2005
- Living under an atomic force microscope. An optimized approach for in vivo investigations on surface alterations towards biomineral nucleation on cyanobacterial cellsGeobiology, 2005
- Cell surface groups of two picocyanobacteria strains studied by zeta potential investigations, potentiometric titration, and infrared spectroscopyJournal of Colloid and Interface Science, 2005
- Production of cobalt binding ligands in a Synechococcus feature at the Costa Rica upwelling domeLimnology and Oceanography, 2005
- Adhesion of Bacterial Exopolymers to α-FeOOH: Inner-Sphere Complexation of Phosphodiester GroupsLangmuir, 2004
- Cell Surface Electrochemical Heterogeneity of the Fe(III)-Reducing Bacteria Shewanella putrefaciensEnvironmental Science & Technology, 2000
- Experimental measurements of the reversibility of metal–bacteria adsorption reactionsChemical Geology, 2000
- Assaying picoplankton distribution by flow cytometry of underway samples collected along a meridional transect across the Atlantic OceanAquatic Microbial Ecology, 2000
- Fourier Transform Infrared microspectroscopy and chemometrics as a tool for the discrimination of cyanobacterial strainsPhytochemistry, 1999
- A reference guide to microbial cell surface hydrophobicity based on contact anglesColloids and Surfaces B: Biointerfaces, 1998