Relationship between global structural parameters and Enzyme Commission hierarchy: Implications for function prediction

In protein databases there is a substantial number of proteins structurally determined but without function annotation. Understanding the relationship between function and structure can be useful to predict function on a large scale. We have analyzed the similarities in global physicochemical parameters for a set of enzymes which were classified according to the four Enzyme Commission (EC) hierarchical levels. Using relevance theory we introduced a distance between proteins in the space of physicochemical characteristics. This was done by minimizing a cost function of the metric tensor built to reflect the EC classification system. Using an unsupervised clustering method on a set of 1025 enzymes, we obtained no relevant clustering formation compatible with EC classification. The distance distributions between enzymes from the same EC group and from different EC groups were compared by histograms. Such analysis was also performed using sequence alignment similarity as a distance. Our results suggest that global structure parameters are not sufficient to segregate enzymes according to EC hierarchy. This indicates that features essential for function are rather local than global. Consequently, methods for predicting function based on global attributes should not obtain high accuracy in main EC classes prediction without relying on similarities between enzymes from training and validation datasets. Furthermore, these results are consistent with a substantial number of studies suggesting that function evolves fundamentally by recruitment, i.e., a same protein motif or fold can be used to perform different enzymatic functions and a few specific amino acids (AAs) are actually responsible for enzyme activity. These essential amino acids should belong to active sites and an effective method for predicting function should be able to recognize them. (C) 2012 Elsevier Ltd. All rights reserved.

CARBON MARKET AND INSTITUTIONS: OPPORTUNITIES IN THE SEARCH OF A NEW MODEL FOR DEVELOPMENT

Seeking alternatives for the economic system to face the several crises it has gone through lately (electrical power, cultural, financing and technological) brought about a new market involving the Kyoto Protocol signatory countries: the carbon market. The present article aims at assessing the carbon market institutional issue in Brazil by identifying the risks and opportunities inherent to the institutional agent characteristics and to that market rules. The research methodology was bibliographic and based on the analysis of the Securities and Exchange Commission of Brazil (Comissao de Valores Mobiliarios and Bolsa Mercantil de Valores) contents. Its theoretical basis rests on concepts of the institution and the new institutional economy. The results show that in spite of the risks and institutional problems it involves, the carbon market is promising due to the opportunities create by new technologies and energies developed to achieve and sustain the capitalist system new cycle, addressed to produce a clean development.

Violência sexual intrafamiliar contra crianças e adolescentes: entre a prevenção do crime e do dano

OBJETIVOS: compreender as representações sociais de membros do Poder Judiciário acerca da prevenção da violência sexual intrafamiliar contra crianças e adolescentes. MÉTODOS: pesquisa de abordagem qualitativa que teve como campo de estudo as 1ª e 2ª Varas dos Crimes contra a Criança e o Adolescente, no Tribunal de Justiça de Pernambuco, com participação de 17 sujeitos (juiz, assessor, técnicos e analistas judiciários). Observação participante, entrevistas semiestruturadas e grupo focal compreenderam as técnicas para coleta de dados, que foram analisados por meio da interpretação dos sentidos. RESULTADOS: a categoria "cultura penal" emergiu dos discursos, bem como suas subcategorias: "prevenção do crime" e "prevenção do dano". CONCLUSÕES: as representações dos sujeitos revelam uma dicotomia, caracterizando o conflito entre a tradição do Poder Judiciário e o direito novo, que abrange os princípios da proteção integral e da prioridade absoluta às crianças e dos adolescentes. O conceito de prevenção da violência sexual intrafamiliar contra crianças e adolescentes deve ser ampliado para além da mera prevenção do crime. A abordagem do problema por meio da prevenção requer que se incorpore ao Poder Judiciário uma cultura penal que abarque os princípios da proteção integral e da prioridade absoluta.