RESUMO
Lectins that bind to HIV envelope glycoprotein can inhibit virus-cell fusion and be used for rational drug design. This paper presents the results of an in silico approach to improve affinity interaction between the cyanobacterial lectin microvirin and its ligand Manα(1-2)Man. Comparative modeling and molecular dynamics tools were used. Additionally, the alanine scanning webserver was used to study the importance of protein residues in the binding site and to guide mutant production. The model obtained presented two homologous domains designated as domains A and B, each consisting of a single strand with triple and antiparallel ß-sheets of (ß1-ß3 and ß6-ß8). Disulfide bonds between the cysteines (Cys60-Cys80, Cys63-Cys78 and Cys8-Cys24) were also found. The highly conserved binding site, including residues Asn44, Ile45, Asp46, Gln54, Asn55, Glu58, Thr59, Gln81, Thr82 and Met83. The RMSD values of the di-mannose and the interaction site were very stable during the molecular dynamics. Calculations of the occupation time of the hydrogen bonds were made for the residues that showed interaction in the complex lectin and ligand. The residue that contributed most to the interaction with Manα(1-2)Man was Asn55. After validation, the model generated remained stable during the entire simulation. Despite its structural similarity with the template we used, our mutant (Thr82Arg) showed a higher affinity interaction with Manα(1-2)Man. Communicated by Ramaswamy H. Sarma.
Assuntos
Lectinas , Manose , Sítios de Ligação , Humanos , Lectinas/química , Ligantes , Manose/química , Simulação de Dinâmica MolecularRESUMO
OBJETIVO: identificar casos de AIDS na população idosa do referido estado. Foram realizadas pesquisas nos dadosdo Departamento de Informática do Sistema Único de Saúde (Datasus) no período de 2001 a 2010. RESULTADOS:evidenciou-se o aumento de diagnósticos positivos em indivíduos com idade?60anos, sendo registrados 259 casosneste período. A principal categoria de exposição foi heterossexual (40,15%), onde os homens representam 74,9% dosdiagnósticos positivos.CONCLUSÃO: a ampliação de campanhas de prevenção e promoção de saúde para a AIDS,são desafios impostos aos profissionais de saúde, devido o aumento da demanda de idosos portadores da doença, esteacréscimo obriga o desenvolvimento cada vez mais acentuado de práticas profissionais capazes de atender tal demanda
Aids has assumed different behaviors in the aged population compared with <60 years in Pará. Increased life expectancyand access to medicines for treating erectile dysfunction have changed the background of sexuality in the elderly. Theaim of this study was to identify cases of aids in the old population of the state. Analyses were performed on data fromthe Informatics Department of the Unified Health System (Datasus) in the period from 2001 to 2010. The data show anincrease in positive diagnoses in individuals aged ? 60 years, with 259 cases recorded in this period. The main risk factorwas heterosexual (40.15%), while men represent 74.9% of positive diagnoses. Aids is a reality that requires the team tovarious health challenges: run prevention campaigns specific to this population and develop a professional practice ableto meet the increased demand from elderly who face this disease.