Leandro S.M. e Miranda

Conformational dissection of Thermomyces lanuginosus lipase in solution

Lipases are triacyl glycerol acyl hydrolases, which catalyze hydrolysis of esters, esterification and transesterification reactions, among others. Some of these enzymes have a large hydrophobic pocket covered by an alpha-helical mobile surface loop (the lid). Protein-protein interactions can occur through adsorption of two open lids of individual lipases. We investigated the conformation and oligomeric state of Thermomyces lanuginosus lipase (TLL) in solution by spectroscopic and mass spectrometry techniques. Information about oligomerization of this important industrial enzyme is only available for TLL crystals; therefore, we have done a throughout investigation of the conformation of this lipase in solution. SDS-PAGE and mass spectrometry analysis of size-exclusion chromatography eluted fractions indicated the presence of both monomeric and dimeric populations of TLL. The stability of the enzyme upon thermal and guanidine hydrochloride treatment was examined by circular dichroism and fluorescence emission spectroscopy. Small angle x-ray scattering and ion mobility mass spectrometry analysis revealed that TLL is found as a mixture of monomers and dimers at the assayed concentrations. Although previous x-ray diffraction data showed TLL as a dimer in the crystal (PDB: 1DT3), to our knowledge our report is the first evidencing that TLL co-exists as stable dimeric and monomeric forms in solution.

Photochemistry under Continuous Flow Conditions

Flow photochemistry is a growing field and has shown many interesting applications in the recent years due to the versatility of the technique related to the flexibility on the construction of the apparatus needed for the required transformation. The use of available materials and commercial source of light makes it an attractive option to several organic chemists who want to start exploring the fruitful field of photochemical reactions.

Continuous Flow Reactions: From Green Chemistry Towards a Green Process

Continuous flow reactions are an emerging technology in the synthesis of high value molecules, such as active pharmaceutical ingredients. Several of them are advantages of this technology, and in the present text that is presented in the context

β-C-ribosyl-1,2,3-triazole analogues of guanosine as potencial antiviral agents against dengue and hepatitis C virus

th Brazilian Meeting on Organic Synthesis – 15 th BMOS – November 10-13, 2013 Campos do Jordao, Brazil -C-ribosyl-1,2,3-triazole analogues of guanosine as potencial antiviral agents against dengue and hepatitis C virus Alexandra Basilio Lopes, Nelilma Correia Romeiro, Amilcar Tanuri, Nadege LubinGermain, Rodrigo Octavio M. A. de Souza, Leandro S.M. Miranda § Federal University of Rio de Janeiro, BOSS Laboratory, † University of Cergy-Pontoise, SOSCO Laboratory, EA 4505, ≠ Federal University of Rio de Janeiro, Molecular Virology Laboratory, Federal University of Rio de Janeiro-Campus Macae Professor Aloisio Teixeira, LICC-Laboratorio Integrado de Computacao Cientifica