Resistance to hydrogen peroxide in textile waste water Bacillus sp.
2007
Gomaa, O.M. (National Center for Radiation Research and Technology, Cairo (Egypt). Radiation Microbiology Dept.) | Azab, K.S.H. (National Center for Radiation Research and Technology, Cairo (Egypt). Radiation Biology Dept.)
A possible mechanism of resistance to hydrogen peroxide (H202) was studied for Bacillus sp. previously isolated from textile wastewater. The results suggest that catalase is involved in the resistance and survival of this bacteria in the presence of low and high concentrations of H2O2. Inducible and constitutive catalase for exponential cells accumulated in extracellular, cytosolic and periplasmic fractions, with the majority compartmentalized in the periplasm. Protein electrophoresis showed a single band for catalase at 40 KDa. When periplasmic fraction was analyzed by Inductive Coupled Plasma (ICP); Fe and Mn were present suggesting that heme-dependent and manganese-dependent catalase might be present as a primary defense. UV - Visible spectrum showed two peaks relevant to catalase and peroxidase standards. Peroxidase activity suggests that HP I catalase-peroxidase is involved in the adaptation process, as a second defense, in response to ac tive oxygen species. Catalase activity was constitutively present in Bacillus cells grown in the absence of H2O2 and its occurrence was dependent on the age of cells, a trait known for HP II-type catalase. The survival of these bacteria in such high concentrations of hydrogen peroxide is a promising feature regarding treatment of wastewater containing hydrogen peroxide.
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