The evolution of functional complexity within the β-amylase gene family in land plants

Background β-Amylases (BAMs) are a multigene family of glucan hydrolytic enzymes playing a key role not only for plant biology but also for many industrial applications, such as the malting process in the brewing and distilling industries. BAMs have been extensively studied in Arabidopsis thaliana where they show a surprising level of complexity in terms of specialization within the different isoforms as well as regulatory functions played by at least three catalytically inactive members. Despite the importance of BAMs and the fact that multiple BAM proteins are also present in other angiosperms, little is known about their phylogenetic history or functional relationship. Results Here, we examined 961 β-amylase sequences from 136 different algae and land plant species, including 66 sequenced genomes and many transcriptomes. The extraordinary number and the diversity of organisms examined allowed us to reconstruct the main patterns of β-amylase evolution in land plants. We identified eight distinct clades in angiosperms, which results from extensive gene duplications and sub- or neo-functionalization. We discovered a novel clade of BAM, absent in Arabidopsis, which we called BAM10. BAM10 emerged before the radiation of seed plants and has the feature of an inactive enzyme. Furthermore, we report that BAM4 – an important protein regulating Arabidopsis starch metabolism – is absent in many relevant starch-accumulating crop species, suggesting that starch degradation may be differently regulated between species. Conclusions BAM proteins originated sometime more than 400 million years ago and expanded together with the differentiation of plants into organisms of increasing complexity. Our phylogenetic analyses provide essential insights for future functional studies of this important class of storage glucan hydrolases and regulatory proteins

Otimização do processo de destilação em planta piloto para produção de etanol hidratado

A destilação é o processo de separação mais amplamente utilizado nas indústrias, onde a separação de componentes de líquidos miscíveis é feita através da diferença de volatilização de cada um destes. Obtendo as variáveis que proporcionam maior rendimento e menor gasto energético, o objetivo do trabalho é otimizar a produção fixando valores de: tempo necessário para produção de bioetanol dentro da especificação de álcool hidratado; taxa de refluxo; e vazão volumétrica de produto de topo. Seguiu-se um planejamento experimental em que os dados foram configurados a partir da metodologia de Delineamento Composto Central Rotacional. Realizaram-se 17 processos de destilação no sistema descontínuo e em cada um destes houve a alteração das variáveis: razão de refluxo, pressão de vapor do refervedor e porcentagem de álcool na mistura a ser destilada, analisando a influência das variáveis de entrada do processo sobre as variáveis respostas: tempo de start-up, volume de bioetanol produzido, vazão (L.h-1) de bioetanol produzido e graduação alcoólica do produto. Durante os experimentos monitorou-se os perfis de temperatura do destilador, alambique, condensador e deflegmador, analisando como o comportamento desses podem afetar o processo de destilação

The Axonal Guidance Receptor Neogenin Promotes Acute Inflammation

Neuronal guidance proteins (NGP) were originally described in the context of axonal growth and migration. Yet recent work has demonstrated that NGPs also serve as guidance cues for immune competent cells. A crucial target receptor for NGPs during embryonic development is the neogenin receptor, however its role during acute inflammation is unknown. We report here that neogenin is abundantly expressed outside the nervous system and that animals with endogenous repression of neogenin (Neo1−/−) demonstrate attenuated changes of acute inflammation. Studies using functional inhibition of neogenin resulted in a significant attenuation of inflammatory peritonitis. In studies employing bone marrow chimeric animals we found the hematopoietic presence of Neo1−/− to be responsible for the attenuated inflammatory response. Taken together our studies suggest that the guidance receptor neogenin holds crucial importance for the propagation of an acute inflammatory response and further define mechanisms shared between the nervous and the immune system