Effect of transition metal compounds on catalase activity of sulfur- reducing bacterial Desulfuromonas acetoxidans cells
O. Vasyliv, S. Hnatush
Ivan Franko National University of Lviv
4, Hrushevskyi St., Lviv 79005, Ukraine
Desulfuromonas acetoxidans are gram-negative obligatory anaerobic sulfur-reducing bacteria. Aerobes and facultative anaerobes possess specific enzymatic antioxidant system which defenses them against toxic and mutagenic compounds or detrimental influence of the oxygen. One of the most crucial components of it is catalase. Itís assumed that lack or low activity of this systemí enzymes of the obligatory anaerobic microorganisms, such as sulfur- or sulfate-reducing bacteria, causes they high sensitivity to the influence of oxygen or toxic compounds, such as transition metals. The influence of FeSO4, FeCl3×6H2O, MnO2, MnCl2×4H2O, NiCl2×6H2O and CoCl2×6H2O on catalase activity of sulfur-reducing bacterial D. acetoxidans cells has been investigated. The highest activity of investigated enzyme has been observed under the influence of 0.5 mM, 1.5 mM and 2.0 mM of NiCl2×6H2O, FeSO4 and CoCl2×6H2O respectively on the second day, 1.5 mM of MnO2 on the third day and 0.5 mM of FeCl3×6H2O and 1.0 mM of MnCl2×4H2O on the fourth day of growth in comparison with control samples.
Keywords: Desulfuromonas acetoxidans, sulfur bacteria, antioxidant defense, catalase, transition metals