Strecker degradation of amino acids promoted by a camphor-derived sulfonamide

A camphor-derived sulfonimine with a conjugated carbonyl group, oxoimine 1 (O2SNC10H13O), reacts with amino acids (glycine, L-alanine, L-phenylalanine, L-leucine) to form a compound O2SNC10H13NC10H14NSO2 (2) which was characterized by spectroscopic means (MS and NMR) and supported by DFT calculations. The product, a single diastereoisomer, contains two oxoimine units connected by a –N= bridge, and thus has a structural analogy to the colored product Ruhemann´s purple obtained by the ninhydrin reaction with amino acids. A plausible reaction mechanism that involves zwitterions, a Strecker degradation of an intermediate imine and water-catalyzed tautomerizations was developed by means of DFT calculations on potential transition states

Genotype and phenotype landscape of MEN2 in 554 medullary thyroid cancer patients: the BrasMEN study

Multiple endocrine neoplasia type 2 (MEN2) is an autosomal dominant genetic disease caused by RET gene germline mutations that is characterized by medullary thyroid carcinoma (MTC) associated with other endocrine tumors. Several reports have demonstrated that the RET mutation profile may vary according to the geographical area. In this study, we collected clinical and molecular data from 554 patients with surgically confirmed MTC from 176 families with MEN2 in 18 different Brazili an centers to compare the type and prevalence of RET mutations with those from other countries. The most frequent mutations, classified by the number of families affected, occur in codon 634, exon 11 (76 families), followed by codon 918, exon 16 (34 families: 26 with M918T and 8 with M918V) and codon 804, exon 14 (22 families: 15 with V804M and 7 with V804L). When compared with other major published series from Europe, there are several similarities and some differences. While the mutations in codons C618, C620, C630, E768 and S891 present a similar prevalence, some mutations have a lower prevalence in Brazil, and others are found mainly in Brazil (G533C and M918V). These results reflect the singular proportion of European, Amerindian and African ancestries in the Brazilian mosaic genome83289298CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DO RIO GRANDE DO SUL - FAPERGSSem informaçãoSem informação2006/60402-1; 2010/51547-1; 2013/01476-9; 2014/06570-6; 2009/50575-4; 2010/51546-5; 2012/21942-116/2551-0000482-

Isolation of natural red colorants from fermented broth using ionic liquid-based aqueous two-phase systems

There is a growing demand for natural colorants. This is prompting the search for new alternative and \"benign\" separation systems allowing higher recoveries, extraction yields, and selectivities. This work investigates the use of aqueous two-phase systems (ATPS) based on ionic liquids as extraction processes for the recovery of red colorants from the fermented broth of Penicillium purpurogenum DPUA 1275. Several ATPS based on quaternary ammonium and imidazolium were studied in this work aiming at separating the red colorants produced from the remaining colorants and contaminant proteins present in the fermented broth. The results suggest that the red colorants can be isolated by an appropriate manipulation of some of the process conditions, such as the use of quaternary ammonium with short alkyl chains, alkaline media, and short tie-line lengths (extraction point systems with lower concentrations of ionic liquid). These conditions allow large partition coefficients for the red colorants (K (red) = 24.4 +/- A 2.3), high protein removal (60.7 +/- A 2.8 %) and selectivity parameters (S (red/prot) = 10.05)

LPS Removal from an E. Coli Fermentation Broth Using Aqueous Two-Phase Micellar System

In biotechnology, endotoxin (LPS) removal from recombinant proteins is a critical and challenging step in the preparation of injectable therapeutics, as endotoxin is a natural component of bacterial expression systems widely used to manufacture therapeutic proteins. The viability of large-scale industrial production of recombinant biomolecules of pharmaceutical interest significantly depends on the separation and purification techniques used. The aim of this work was to evaluate the use of aqueous two-phase micellar system (ATPMS) for endotoxin removal from preparations containing recombinant proteins of pharmaceutical interest, such as green fluorescent protein (GFPuv). Partition assays were carried out initially using pure LPS, and afterwards in the presence of E. coli cell lysate. The ATPMS technology proved to be effective in GFPuv recovery, preferentially into the micelle-poor phase (K(GFPuv) < 1.00), and LPS removal into the micelle-rich phase (%REM(LPS) > 98.00%). Therefore, this system can be exploited as the first step for purification in biotechnology processes for removal of higher LPS concentrations. (C) 2010 American Institute of Chemical Engineers Biotechnol. Prog., 26: 1644-1653, 2010Capes - BrazilNational Council for Scientific and Technological Development (CNPq - Brazil)State of Sao Paulo Research Support Foundation (Fapesp - Brazil

Extraction of tetracycline from fermentation broth using aqueous two-phase systems composed of polyethylene glycol and cholinium-based salts

Aiming at developing not only cheaper but also biocompatible and sustainable extraction and purification processes for antibiotics, in this work it was evaluated the ability of aqueous two-phase systems (ATPS) composed of polyethylene glycol (PEG) and cholinium-based salts to extract tetracycline from the fermented broth of Streptomyces aureofaciens. Conventional polymer/salt and salt/salt ATPS were also studied for comparison purposes. The novel systems here proposed are able to extract tetracycline directly from the fermentation broth with extraction efficiencies higher than 80%. A tailored extraction ability of these systems can also be achieved, with preferential extractions either for the polymer- or salt-rich phases, and which further depend on the cholinium-based salt employed. The gathered results support the applicability of biocompatible ATPS in the extraction of antibiotics from complex matrices and can be envisaged as valuable platforms to be applied at the industrial level by pharmaceutical companies. (c) 2013 Elsevier Ltd. All rights reserved

Non-native states of cardosin A induced by acetonitrile: Activity modulation via polypeptide chains rearrangements

Cardosin A (EC: 3.4.23) is an enzyme containing two polypeptide chains, purified from pistils of Cynara cardunculus L., a cardoon, used for milk clotting in cheese making. It is amemberof the aspartic proteinases (APs), like pepsin and HIV-proteinase that are composed by two symmetric units comprising the active site. Cardosin A is thought to be involved in many cellular events such as in pollen–pistil interaction and adhesion dependent recognition mechanisms. In the present study, the structural and activity effects of different amounts of acetonitrile (ACN) in cardosin A are presented. The results indicate that low ACN concentrations (up to 10% ACN) reversibly stimulate theenzymeactivity accompanied by slight secondary structure induction. In light of the structural and stability studies performed so far, cardosin A can adopt conformational alterations that can result in activity modulation via polypeptide chains rearrangements.Cardosin A;Acetonitrile; Aspartic proteinases; Foldin

The expression of cyclooxygenase 2 in retinoblastoma: Primary enucleated eyes and enucleation after conservative treatment

PURPOSE: To provide insight into the relationship between cyclooxygenase,2 (COX-2) expression and histopathologic features of retinoblastoma specimens treated either by primary or secondary enucleation.DESIGN: Laboratory investigation.METHODS: Twenty-five retinoblastoma specimens received between 1994 and 2003 were retrieved for this study from the Ocular Pathology Registry, Federal University of São Paulo, Brazil and the Henry C. Witelson Ocular Pathology Laboratory and Registry, McGill University, Montreal, Canada. the specimens retrieved were divided into two groups: Group 1, enucleation was performed as a form of primary treatment (n = 15) and Group 11, enucleation after failure of conservative treatment (n = 10). Patient information and formalin,fixed, paraffin-embedded specimens were obtained. New sections of these blocks were used for hematoxylin and eosin stain and for immunoassay using a monoclonal mouse anti-COX,2 antibody. Two independent ophthalmic pathologists reviewed all of the microslides.RESULTS: Twenty-three specimens (92%) presented a high expression of COX,2 (15 in Group 1; eight in Group 11) and there was no statistical difference in COX,2 expression between the two groups (P = .07). However, all specimens expressed COX-2 to a different degree. the areas of tumor invasion were positive for COX-2 in 87.5% of the two groups.CONCLUSION: Most retinoblastoma specimens revealed a high COX 2 expression. Future studies will be necessary to correlate the high expression of COX-2 in retinoblastoma and a possible applicability of anti-COX-2 medications in the treatment of these tumors.McGill Univ, Henry C Witelson Ocular Pathol Lab, Montreal, PQ, CanadaUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, BrazilUniversidade Federal de São Paulo, Pediat Oncol Inst, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, BrazilUniversidade Federal de São Paulo, Pediat Oncol Inst, São Paulo, BrazilWeb of Scienc

Copper Complexes with 1,10-Phenanthroline Derivatives: Underlying Factors Affecting Their Cytotoxicity

The interpretation of in vitro cytotoxicity data of Cu(II)-1,10-phenanthroline (phen) complexes normally does not take into account the speciation that complexes undergo in cell incubation media and its implications in cellular uptake and mechanisms of action. We synthesize and test the activity of several distinct Cu(II)-phen compounds; up to 24 h of incubation, the cytotoxic activity differs for the Cu complexes and the corresponding free ligands, but for longer incubation times (e.g., 72 h), all compounds display similar activity. Combining the use of several spectroscopic, spectrometric, and electrochemical techniques, the speciation of Cu-phen compounds in cell incubation media is evaluated, indicating that the originally added complex almost totally decomposed and that Cu(II) and phen are mainly bound to bovine serum albumin. Several methods are used to disclose relationships between structure, activity, speciation in incubation media, cellular uptake, distribution of Cu in cells, and cytotoxicity. Contrary to what is reported in most studies, we conclude that interaction with cell components and cell death involves the separate action of Cu ions and phen molecules, not [Cu(phen)(n)] species. This conclusion should similarly apply to many other Cu-ligand systems reported to date.Fundacao para a Ciencia e Tecnologia (FCT)Portuguese Foundation for Science and TechnologyEuropean Commission [UID/Multi/04349/2019, UIDB/00100/2020, UID/QUI/50006/2019, UID/BIO/04565/2020]FCTPortuguese Foundation for Science and TechnologyEuropean Commission [IF/00841/2012, IF/00007/2015, SFRH/BD/108743/2015]Programa Operacional Regional de Lisboa 2020 [007317]PROTEOMASS Scientific SocietyCOST Action, NECTAR (Network for Equilibria and Chemical Thermodynamics Advanced Research) - COST (European Cooperation in Science and Technology) [CA18202]info:eu-repo/semantics/publishedVersio