title: Kinetic studies on elemental sulfur oxidation by Acidithiobacillus ferrooxidans: sulfur limitation and activity of free and adsorbed bacteria.
abstract: The kinetics of sulfur oxidation by Acidithiobacillus ferrooxidans in shaking flasks and a 10-L reactor was studied. The observed linearity of growth and sulfur oxidation was explained by sulfur limitation. Total cell yield was not significantly different for exponential growth as compared to growth during the sulfur-limiting phase. Kinetic studies of sulfur oxidation by growing and nongrowing bacteria indicated that both free and adsorbed bacteria oxidize sulfur. Changes in the number of free bacteria rather than cells adsorbed on sulfur were better predictors of the kinetics of sulfur oxidation, indicating that the free bacteria were performing sulfur oxidation. The active growth phase always followed adsorption of bacteria on sulfur; however, the special metabolic role of adsorbed bacteria was unclear. Their activity in sulfur solubilization was considered.
authors.affiliation: Department of Biochemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno, Czech Republic.
authors.forename: Pavla
authors.initials: P
authors.lastname: Ceskova
authors.forename: Martin
authors.initials: M
authors.lastname: Mandl
authors.forename: Sarka
authors.initials: S
authors.lastname: Helanova
authors.forename: Jitka
authors.initials: J
authors.lastname: Kasparovska
mesh_terms: D000327:Adsorption; D004563:Electrochemistry / Q000379:methods; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D008954:Models, Biological; D008956:Models, Chemical; D010084:Oxidation-Reduction; D012680:Sensitivity and Specificity; D013431:Sulfates / Q000032:analysis*; D013455:Sulfur / Q000378:metabolism* / Q000493:pharmacokinetics; D013855:Thiobacillus / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D013431:Sulfates; D013455:Sulfur