Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Níquel/metabolismo , Microbiologia do Solo , Acidithiobacillus/classificação , Acidithiobacillus/genética , Acidithiobacillus/isolamento & purificação , Bactérias/genética , DNA Ribossômico/classificação , DNA Ribossômico/genética , Resíduos Industriais , Leptospiraceae/classificação , Leptospiraceae/genética , Leptospiraceae/isolamento & purificação , Mineração , Níquel/química , FilogeniaRESUMO
The kinetics of conversion of sulfur compounds by Halothiobacillus neapolitanus DSM 15147 bacteria was studied in the presence of steel samples. It was shown that the presence of steel altered the known pathway of sulfur compound oxidation by thiobacteria. Production of atomic hydrogen via the interaction between biogenic sulfuric acid and steel enhanced secondary production of intermediates and decreased the content of sulfate produced previously. The process was accompanied by pH elevation and continuation of intense growth of the thiobacterium culture. Thiobacteria formed a corrosive medium, which caused metal destruction. The protective properties of anticorrosive coatings 225 LS and 640 mk were tested. It was shown that these coatings protected steel from the destructive effect of biogenic sulfuric acid.
Assuntos
Halothiobacillus/metabolismo , Aço/química , Compostos de Enxofre/metabolismo , Corrosão , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Halothiobacillus/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Oxirredução , Ácidos Sulfúricos/efeitos adversos , Ácidos Sulfúricos/metabolismo , TensoativosRESUMO
Bacteria belonging to different taxonomic and physiological groups (members of the genera Pseudomonas, Brevibacterium, Rhodopseudomonas, and Lactococcus) are able to form intracellular cobalt- and chromium-containing magnetic inclusions. The paper deals with the structure and the intracellular localization of these inclusions and their similarity to the known noncrystalline iron-containing magnetic inclusions. The possible biological role of the magnetic inclusions is discussed.
