6 documents found, page 1 of 1
Characterization of the first two toxins isolated from the venom of the ancient...
Oliveira,Natiela Beatriz de; Magalhães,Ana Carolina Martins; Bloch Jr.,Carlos; Beirão,Paulo Sérgio Lacerda; Silva,Anita de Oliveira; Melani,Rafael D.Abstract Background: Almost all Tityus characterized toxins are from subgenera Atreus and Tityus, there are only a few data about toxins produced by Archaeotityus, an ancient group in Tityus genus. Methods: Tityus (Archaeotityus) mattogrossensis crude venom was fractionated by high performance liquid chromatography, the major fractions were tested in a frog sciatic nerve single sucrose-gap technique. Two fracti...
Polypyridyl Ruthenium Complexes: Novel DNA-Intercalating Agents against Human B...
Barolli,João P.; Corrêa,Rodrigo S.; Miranda,Fabio S.; Ribeiro,Juliana U.; Bloch Jr.,Carlos; Ellena,Javier; Moreno,Virtudes; Cominetti,Márcia R.This paper describes a new series of four DNA-intercalating agents with promising anticancer activities, based on ruthenium(II) with the planar ligand dpqQX (dpqQX = dipyrido[3,2-a:2',3'-c]quinoxaline[2,3-b]quinoxaline). The complexes identified as trans-[RuCl2(dppb)(dpqQX)], cis-[RuCl2(dppb)(dpqQX)], ct-[RuCl(CO)(dppb)(dpqQX)]PF6 and ct-[RuCl2(PPh3)2(dpqQX)] (dppb = 1,4-bis(diphenylphosphine)butane and PPh3 = ...
Cinerascetins, New Peptides from Hypsiboas cinerascens: MALDI LIFT-TOF-MS/MS de...
Almeida,Richardson A.; Gordo,Marcelo; Silva,Felipe M. A. da; Araújo,Rafael C. de; Ramada,Marcelo H. S.; Abrão,Fernando Y.; Costa,Túlio O. G.The continuous search for antimicrobial candidates pushes the pursuit of compounds in the most diverse organisms. Amphibians are known as a prolific source of antibacterial peptides. Based on the rich biodiversity of the Amazon region the unexplored green-tree frog (Hypsiboas cinerascens) was studied for its skin secretion peptide content. Chromatographic separations and established tandem mass spectrometry (MS...
Isolation and amino acid sequencing by MALDI-TOF-MS/MS of a novel antimicrobial...
Costa,Túlio O. G.; Almeida,Richardson A.; Melo,Jorge T.; Koolen,Hector H. F.; Silva,Felipe M. A. da; Leite,José Roberto S. A.; Prates,Maura V.By means of chromatographic techniques, a novel anionic peptide, named otacidin, was isolated from the skin secretions of tree Brazilian anurans Osteocephalus taurinus. The de novo sequencing of the amino acids was performed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS/MS) analyses. The antimicrobial potential of this novel metabolite was evaluated against Escher...
Isolation and Characterisation of a Reserve Protein from the Seeds of Cereus ja...
Costa,Itayguara Ribeiro da; Souza,Petrônio Augusto Simão de; Bloch Jr.,Carlos; Llamoca-Zárate,Romulo Marino; Campos,Francisco A. P.We describe here the isolation and characterisation of a major reserve protein from the seeds of Cereus jamacaru. (Cactaceae). This protein has a molecular mass of 5319 kDa and was isolated by a combination of gel filtration chromatography and reverse phase HPLC. The amino acid composition of the protein was determined and it was shown to have similarities with the amino acid composition of several proteins fro...
Zinc binding to lambda phage DNA studied by voltammetric techniques
Souza,Jurandir R. de; Castro,Clarissa S. P. de; Bloch Jr.,CarlosBinding of zinc to lambda phage DNA was investigated by differential pulse voltammetry and cyclic voltammetry. These methods rely on the direct monitoring of reduction and oxidation current of zinc in the absence and presence of this virion DNA. Titration graphs of Zn2+ with DNA were obtained in the concentration ranges from 3.57 x 10-12 to 3.92 x 10-11 mol L-1 and 6.97 x 10-12 to 5.56 x 10-11 mol L-1. These da...