Heterogeneities in lipids and proteins structures: studies by advanced fluorescence techniques

• Grant number: 14/26895-7
• Support Opportunities: Regular Research Grants
• Duration: May 01, 2015 - April 30, 2017
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Amando Siuiti Ito
• Grantee: Amando Siuiti Ito
• Host Institution: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto (FFCLRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Many biological processes are related to interactions between molecules and complex structures like the cell membrane, where organized lipid domains play relevant role. Even interactions in two components systems, like enzyme and substrate, depend on complex conformational dynamics, where heterogeneities are essential for the biological function. Advances in studies of both systems were achieved using experimental techniques derived from coupling of confocal microscopy and fluorescence spectroscopy. The detected fluorescence originates in very small volume and it is possible to examine events related to the emission by very few fluorophores, and even from a single molecule, and the fluorescence fluctuations can be analysed using time correlation techniques. Furthermore, decay profiles can be obtained, which are associated to very small regions of the sample, allowing the recovery of images from fluorescence lifetimes. We will apply advanced techniques that can provide information not possible to obtain from conventional fluorescence, to study heterogeneities in cell membranes and enzymes. We expect to contribute to descriptions and models for the biological membrane taking into account the cooperativity between distinct dynamical elements organized in the membranes, and for the enzymatic catalysis, based on the complex conformational dynamics of proteins. We will study specifically effects of heterogeneities in giant unilamelar vesicles in interaction with lipid nanoparticles containing miltefosine, virus fusion peptides and proteins. The role of protein conformational heterogeneities in the enzymatic activity of xylanase also will be investigated. (AU)

Scientific publications

(5)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

TOZONI, J. R.; BARBOSA NETO, N. M.; RIBEIRO, C. A.; PAZIN, W. M.; ITO, A. S.; BORISSEVITCH, I. E.; MARLETTA, A.. Relationship between porphyrin aggregation and formation of porphyrin ring structures in poly(n-alkyl methacrylate)/porphyrin blends. Polymer, v. 102, p. 136-142, OCT 12 2016. (09/17077-0, 14/26895-7)

DA GAMA BITENCOURT, JOSE JARDES; PAZIN, WALLANCE MOREIRA; ITO, AMANDO SIUITI; BARIONI, MARINA BERARDI; PINTO, CAROLLINE DE PAULA; DOS SANTOS, MARIA APARECIDA; SANTOS GUIMARAES, THALES HENRIQUE; MACHADO DOS SANTOS, MARCIA REGINA; VALDUGA, CLAUDETE JUSTINA. Miltefosine-loaded lipid nanoparticles: Improving miltefosine stability and reducing its hemolytic potential toward erythtocytes and its cytotoxic effect on macrophages. Biophysical Chemistry, v. 217, p. 20-31, OCT 2016. (09/17077-0, 14/26895-7)

MENDANHA, SEBASTIAO ANTONIO; MARQUEZIN, CASSIA ALESSANDRA; ITO, AMANDO SIUITI; ALONSO, ANTONIO. Effects of nerolidol and limonene on stratum corneum membranes: A probe EPR and fluorescence spectroscopy study. International Journal of Pharmaceutics, v. 532, n. 1, p. 547-554, OCT 30 2017. (14/26895-7)

SILVA, DEBORA E. S.; CALI, MARIANA P.; PAZIN, WALLANCE M.; CARLOS-LIMA, ESTEVAO; SALLES TREVISAN, MARIA TERESA; VENANCIO, TIAGO; ARCISIO-MIRANDA, MANOEL; ITO, AMANDO S.; CARLOS, ROSE M.. Luminescent Ru(II) Phenanthroline Complexes as a Probe for Real-Time Imaging of A beta Self-Aggregation and Therapeutic Applications in Alzheimer's Disease. Journal of Medicinal Chemistry, v. 59, n. 19, p. 9215-9227, OCT 13 2016. (12/02065-0, 14/26895-7, 14/07935-8, 14/12538-8, 14/24643-0)

BRANDAO, MARIANA P.; IWAKURA, RICARDO; HONORATO-SOBRINHO, ABRAAO A.; HALEPLIAN, KAIQUE; ITO, AMANDO S.; CONTI DE FREITAS, LUIZ C.; BACHMANN, LUCIANO. Optical Characterization of Parathyroid Tissues. Applied Spectroscopy, v. 70, n. 10, p. 1709-1716, OCT 2016. (11/07960-4, 14/26895-7, 12/02460-6)