The structures of Micrococcus lysodeikticus catalase, its ferryl intermediate (compound II) and NADPH complex

The crystal structure of the bacterial catalase from Micrococcus lysodeikticus has been refined using the gene-derived sequence both at 0.88 Angstrom resolution using data recorded at 110 K and at 1.5 Angstrom resolution with room-temperature data. The atomic resolution structure has been refined with individual anisotropic atomic thermal parameters. This has revealed the geometry of the haem and surrounding protein, including many of the H atoms, with unprecedented accuracy and has characterized functionally important hydrogen-bond interactions in the active site. The positions of the H atoms are consistent with the enzymatic mechanism previously suggested for beef liver catalase. The structure reveals that a 25 Angstrom long channel leading to the haem is filled by partially occupied water molecules, suggesting an inherent facile access to the active site. In addition, the structures of the ferryl intermediate of the catalase, the so-called compound II, at 1.96 Angstrom resolution and the catalase complex with NADPH at 1.83 Angstrom resolution have been determined. Comparison of compound II and the resting state of the enzyme shows that the binding of the O atom to the iron (bond length 1.87 Angstrom) is associated with increased haem bending and is accompanied by a distal movement of the iron and the side chain of the proximal tyrosine. Finally, the structure of the NADPH complex shows that the cofactor is bound to the molecule in an equivalent position to that found in beef liver catalase, but that only the adenine part of NADPH is visible in the present structure

The measurement and perception of sulphurous odour pollutants

Imperial Users onl

Sociopolitical orientation of the youth community in Russia: the behavior modification approach to young people in the framework of higher education institutions

The paper is an attempt to analyze the state of the sociopolitical orientation of young people in Russia which is caused by the political process launched in the course of reforms. Some recommendations on the behavior modification in the framework of the social institution of elite cadres training – higher school – are also presented. The authors of the article substantiate the following idea: while studying at a higher education institution, the individual must be able to acquire the necessary expertise that allows them to take up active life, civic, and political positions. Examples of such competencies are: general legal literacy; the ability to critically evaluate information, etc. Some particular conditions for the formation of young people’s outlook on life, the formation of their sociocultural and cultural political positions that should be implemented in higher education through educational, scientific, and innovative leisure activities are presented in the article; the recommendations for their formation in higher education institutions are also given