Tracking the origin and divergence of cholinesterases and neuroligins: the evolution of synaptic proteins

14. International Symposium on Cholinergic Mechanisms (ISCM), Hangzhou, 2013/05/05-9A cholinesterase activity can be found in all kingdoms of living organism, yet cholinesterases involved in cholinergic transmission appeared only recently in the animal phylum. Among various proteins homologous to cholinesterases, one finds neuroligins. These proteins, with an altered catalytic triad and no known hydrolytic activity, display well-identified cell adhesion properties. The availability of complete genomes of a few metazoans provides opportunities to evaluate when these two protein families emerged during evolution. In bilaterian animals, acetylcholinesterase co-localizes with proteins of cholinergic synapses while neuroligins co-localize and may interact with proteins of excitatory glutamatergic or inhibitory GABAergic/glycinergic synapses. To compare evolution of the cholinesterases and neuroligins with other proteins involved in the architecture and functioning of synapses, we devised a method to search for orthologs of these partners in genomes of model organisms representing distinct stages of metazoan evolution. Our data point to a progressive recruitment of synaptic components during evolution. This finding may shed light on the common or divergent developmental regulation events involved into the setting and maintenance of the cholinergic versus glutamatergic and GABAergic/glycinergic synapses

ESTHER, the database of the α/β-hydrolase fold superfamily of proteins: tools to explore diversity of functions

The ESTHER database, which is freely available via a web server (http://bioweb.ensam.inra.fr/esther) and is widely used, is dedicated to proteins with an a/b-hydrolase fold, and it currently contains >30 000 manually curated proteins. Herein, we report those substantial changes towards improvement that we have made to improve ESTHER during the past 8 years since our 2004 update. In particular, we generated 87 new families and increased the coverage of the UniProt Knowledgebase (UniProtKB). We also renewed the ESTHER website and added new visualization tools, such as the Overall Table and the Family Tree. We also address two topics of particular interest to the ESTHER users. First, we explain how the different enzyme classifications (bacterial lipases, peptidases,carboxylesterases) used by different communities of users are combined in ESTHER. Second, we discuss how variations of core architecture or in predicted active site residues result in a more precise clustering of families, and whether this strategy provides trustable hints to identify enzymelike proteins with no catalytic activity

ThYme: a database for thioester-active enzymes

The ThYme (Thioester-active enzYme; http://www.enzyme.cbirc.iastate.edu) database has been constructed to bring together amino acid sequences and 3D (tertiary) structures of all the enzymes constituting the fatty acid synthesis and polyketide synthesis cycles. These enzymes are active on thioester-containing substrates, specifically those that are parts of the acyl-CoA synthase, acyl-CoA carboxylase, acyl transferase, ketoacyl synthase, ketoacyl reductase, hydroxyacyl dehydratase, enoyl reductase and thioesterase enzyme groups. These groups have been classified into families, members of which are similar in sequences, tertiary structures and catalytic mechanisms, implying common protein ancestry. ThYme is continually updated as sequences and tertiary structures become available

Campanha de prevenção em estomatologia na clínica odontológica do Centro Universitário de Volta Redonda (UniFOA)

A Campanha de Prevenção em Estomatologia visa proporcionar aos alunos do 5º e 6º períodos do Curso de Odontologia, a oportunidade de executar exames clínicos visando detectar precocemente lesões de maior incidência em tecido mole, bem como lesões precursoras ou malignas suspeitas de câncer, beneficiando a população através de educação preventiva, orientação para tratamento adequado e iniciação científica. Os objetivos incluem (a) alertar e motivar a população para a prevenção das lesões de boca e seus fatores de risco, que originam as lesões malignas, (b) verificar a incidência das alterações da cavidade bucal e (c) diagnosticar precocemente lesões passíveis de malignidade, prevenção e promoção da saúde. A metodologia empregada inclui o exame clínico do paciente, educação preventiva (através do ensino de técnica de escovação, uso do fio dental, utilização do limpador de língua) e distribuição de folders, cartazes e manuais. A pesquisa de campo, previamente aprovada pelo Comitê de Ética institucional, está sendo efetuada através de registro de dados dos pacientes em formulário, após assinatura do Termo de Consentimento Livre e Esclarecido. Nossa perspectiva é aumentar o conhecimento dos pacientes sobre lesões da cavidade oral, visando a Promoção da Saúde

Calm ICT design in hotels: A critical review of applications and implications

There has recently been a call for revisiting the effect of ICT on guest experience in hotels. This is because ICT solutions can act not only as enhancers of hotel guest experience, but also as its inhibitors. In response to this call, the notion of calm ICT design has recently been introduced. Calm ICT design describes the ICT solutions that are used only when and if required, thus not calling user’s attention at all times. Although this concept is highly relevant to the hospitality industry, it has never been systematically considered within. This paper conceptualizes calm ICT design for application in the hospitality context. To this end, it analyzes the ICT solutions that are currently employed by hospitality businesses from the calm ICT design perspective; discusses how the opportunities offered by calm ICT design can be better capitalized upon by hospitality managers; and outlines directions for future research

The PE-PPE Domain in Mycobacterium Reveals a Serine α/β Hydrolase Fold and Function: An In-Silico Analysis

The PE and PPE proteins first reported in the genome sequence of Mycobacterium tuberculosis strain H37Rv are now identified in all mycobacterial species. The PE-PPE domain (Pfam ID: PF08237) is a 225 amino acid residue conserved region located towards the C-terminus of some PE and PPE proteins and hypothetical proteins. Our in-silico sequence analysis revealed that this domain is present in all Mycobacteria, some Rhodococcus and Nocardia farcinica genomes. This domain comprises a pentapeptide sequence motif GxSxG/S at the N-terminus and conserved amino acid residues Ser, Asp and His that constitute a catalytic triad characteristic of lipase, esterase and cutinase activity. The fold prediction and comparative modeling of the 3-D structure of the PE-PPE domain revealed a “serine α/β hydrolase” structure with a central β-sheet flanked by α-helices on either side. The structure comprises a lid insertion with a closed structure conformation and has a solvent inaccessible active site. The oxyanion hole that stabilizes the negative charge on the tetrahedral intermediate has been identified. Our findings add to the growing list of serine hydrolases in mycobacterium, which are essential for the maintenance of their impermeable cell wall and virulence. These results provide the directions for the design of experiments to establish the function of PE and PPE proteins

Transcriptome Analysis of the Oriental Fruit Fly (Bactrocera dorsalis)

The oriental fruit fly, Bactrocera dorsalis (Hendel), is one of the most economically important pests in the world, causing serious damage to fruit production. However, lack of genetic information on this organism is an obstacle to understanding the mechanisms behind its development and its ability to resist insecticides. Analysis of the B. dorsalis transcriptome and its expression profile data is essential to extending the genetic information resources on this species, providing a shortcut that will support studies on B. dorsalis.We performed de novo assembly of a transcriptome using short read sequencing technology (Illumina). The results generated 484,628 contigs, 70,640 scaffolds, and 49,804 unigenes. Of those unigenes, 27,455 (55.13%) matched known proteins in the NCBI database, as determined by BLAST search. Clusters of orthologous groups (COG), gene orthology (GO), and the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations were performed to better understand the functions of these unigenes. Genes related to insecticide resistance were analyzed in additional detail. Digital gene expression (DGE) libraries showed differences in gene expression profiles at different developmental stages (eggs, third-instar larvae, pupae, and adults). To confirm the DGE results, the expression profiles of six randomly selected genes were analyzed.This transcriptome greatly improves our genetic understanding of B. dorsalis and makes a huge number of gene sequences available for further study, including both genes of known importance and genes of unknown function. The DGE data provide comprehensive insight into gene expression profiles at different developmental stages. This facilitates the study of the role of each gene in the developmental process and in insecticide resistance

Carboxylic ester hydrolases from hyperthermophiles

Carboxylic ester hydrolyzing enzymes constitute a large group of enzymes that are able to catalyze the hydrolysis, synthesis or transesterification of an ester bond. They can be found in all three domains of life, including the group of hyperthermophilic bacteria and archaea. Esterases from the latter group often exhibit a high intrinsic stability, which makes them of interest them for various biotechnological applications. In this review, we aim to give an overview of all characterized carboxylic ester hydrolases from hyperthermophilic microorganisms and provide details on their substrate specificity, kinetics, optimal catalytic conditions, and stability. Approaches for the discovery of new carboxylic ester hydrolases are described. Special attention is given to the currently characterized hyperthermophilic enzymes with respect to their biochemical properties, 3D structure, and classification