PATRICK JACK SPENCER

PATRICK JACK SPENCER

(Fonte: Lattes)

Resumo

Possui graduação em Ciências Biológicas pela Universidade Presbiteriana Mackenzie (1991), mestrado em Tecnologia Nuclear pela Universidade de São Paulo (1995) e doutorado em Tecnologia Nuclear pela Universidade de São Paulo (2000) tendo sido bolsista sandwich no US Army Medical Research Institute for Infeccious Diseases (98-99). É responsável pelo Biotério de criação e manutenção de animais de laboratório do IPEN. Tem experiência na área de Bioquímica, com ênfase em Proteínas, atuando principalmente nos seguintes temas: veneno, proteínas, bothrops, irradiação e miotoxina.(Texto extraído do Currículo Lattes em 22 dez. 2021)

Página do item completo

Resultados de Busca

Agora exibindo 1 - 2 de 2

Protein identification from the parotoid macrogland secretion of Duttaphrynus melanostictus
2019 - MARIANO, DOUGLAS O.C.; MESSIAS, MARCELA D.G.; SPENCER, PATRICK J.; PIMENTA, DANIEL C.
Background: Bufonid parotoid macrogland secretion contains several low molecular mass molecules, such as alkaloids and steroids. Nevertheless, its protein content is poorly understood. Herein, we applied a sample preparation methodology that allows the analysis of viscous matrices in order to examine its proteins. Methods: Duttaphrynus melanostictus parotoid macrogland secretion was submitted to ion-exchange batch sample preparation, yielding two fractions: salt-displaced fraction and acid-displaced fraction. Each sample was then fractionated by anionic-exchange chromatography, followed by in-solution proteomic analysis. Results: Forty-two proteins could be identified, such as acyl-CoA-binding protein, alcohol dehydrogenase, calmodulin, galectin and histone. Moreover, de novo analyses yielded 153 peptides, whereas BLAST analyses corroborated some of the proteomicidentified proteins. Furthermore, the de novo peptide analyses indicate the presence of proteins related to apoptosis, cellular structure, catalysis and transport processes. Conclusions: Proper sample preparation allowed the proteomic and de novo identification of different proteins in the D. melanostictus parotoid macrogland secretion. These results may increase the knowledge about the universe of molecules that compose amphibian skin secretion, as well as to understand their biological/physiological role in the granular gland.
Biochemical analyses of proteins from duttaphrynus melanostictus (Bufo melanostictus) skin secretion
2018 - MARIANO, DOUGLAS O.C.; MESSIAS, MARCELA Di G.; PREZOTTO-NETO, JOSE P.; SPENCER, PATRICK J.; PIMENTA, DANIEL C.
A crucial step in scientific analysis can be sample preparation, and its importance increases in the same rate as the sensitivity of the following employed/desired analytical technique does. The need to analyze complex, viscous matrices is not new, and diverse approaches have been employed, with different success rates depending on the intended molecules. Solid-phase extraction, for example, has been successfully used in sample preparation for organic molecules and peptides. However, due to the usual methodological conditions, biologically active proteins are not successfully retrieved by this technique, resulting in a low rate of protein identification reported for the viscous amphibian skin secretion. Here we describe an ion-exchange batch processing sample preparation technique that allows viscous or adhesive materials (as some amphibian skin secretions) to be further processed by classical liquid chromatography approaches. According to our protocol, samples were allowed to equilibrate with a specific resin that was washed with appropriated buffers in order to yield the soluble protein fraction. In order to show the efficiency of our methodology, we have compared our results to classically prepared skin secretion, i.e., by means of filtration and centrifugation. After batch sample preparation, we were able to obtain reproductive resolved protein chromatographic profiles, as revealed by SDS-PAGE, and retrieve some biological activities, namely, hydrolases belonging to serine peptidase family. Not only that, but also the unbound fraction was rich in low molecular mass molecules, such as alkaloids and steroids, making this sample preparation technique also suitable for the enrichment of such molecules.