Enterococcus faecalis exhibits high resistance to oxidative stress. Several enzymes are responsible for this trait. The role of alkyl hydroperoxide reductase (Ahp), thiol peroxidase (Tpx), and NADH peroxidase (Npr) in oxidative stress defense was recently characterized. Enterococcus faecalis, in contrast to many other streptococci, contains a catalase (KatA), but this enzyme can only be formed ...

Rhodococcus equi is one of the most widespread causes of disease in foals aged from 1 to 6 months. R. equi possesses antioxidant defense mechanisms to protect it from reactive oxygen metabolites such as hydrogen peroxide (H(2)O(2)) generated during the respiratory burst of phagocytic cells. These defense mechanisms include enzymes such as catalase, which detoxify hydrogen peroxide. Recently, an...

Compound verbs in Korean show properties of both syntactic phrases and lexical items. Earlier studies of compound verbs have either assumed two homonymous types, i.e. one as a syntactic phrase and the other as a lexical item, or posited some sort of transformation from a syntactic phrase into a lexical item. In this paper, I show empirical and conceptual problems for earlier studies, and presen...

Little in general is known about how heme proteins are assembled from their constituents in cells. The Gram-positive bacterium Enterococcus faecalis cannot synthesize heme and does not depend on it for growth. However, when supplied with heme in the growth medium the cells can synthesize two heme proteins; catalase (KatA) and cytochrome bd (CydAB). To identify novel factors important for catala...

BACKGROUND Bacillus pumilus cells exhibit a significantly higher resistance to hydrogen peroxide compared to closely related Bacilli like Bacillus subtilis. RESULTS In this study we analyzed features of the catalase KatX2 of B. pumilus as one of the most important parts of the cellular response to hydrogen peroxide. KatX2, the vegetative catalase expressed in B. pumilus, was compared to the v...

The Helicobacter pylori energy sensor TlpD determines tactic behaviour under low energy conditions and is important in vivo. We explored protein-protein interactions of TlpD and their impact on TlpD localisation and function. Pull-down of tagged TlpD identified protein interaction partners of TlpD, which included the chemotaxis histidine kinase CheAY2, the central metabolic enzyme aconitase (Ac...

Staphylococcus aureus is a pathogen and a commensal bacterial species that is found in humans. Bacterial two-component systems (TCSs) sense and respond to environmental stresses, which include antimicrobial agents produced by other bacteria. In this study, we analyzed the relation between the TCS SrrAB and susceptibility to the hydrogen peroxide (H2O2) that is produced by Streptococcus sanguini...