Cover, Masthead, and Table of Contents PSF Vol. 41 no. 2

Cover, Masthead, and Table of Contents PSF Vol. 41 no.

Evaluation of the Tat export pathway for the production of recombinant proteins in Escherichia coli

Recently, the twin-arginine translocation (Tat) pathway has raised interest due to reports of its unique proofreading ability to export correctly folded proteins. However, only a few recombinant proteins fused to an N-terminal Tat signal peptide have been reported to be exported via Tat. The hypothesis for this thesis was to evaluate whether the range of proteins of interest that can be exported by the Tat pathway can be extended by C-terminally fusing them to a natural Tat substrate (NTS). Thus, the NTS would act as a soluble carrier to improve cytoplasmic solubility and facilitate Tat export. Moreover, the CyDisCo technology enabling cytoplasmic formation of disulphide bonds was investigated to reach this goal. Initially, a robust fractionation method was developed to assess protein localisation with due diligence. A panel of NTS and reporter proteins were evaluated for the respective role of the soluble carrier and the protein of interest. None of the selected NTS and only PhoA and hGH of the tested reporter proteins were shown to export specifically via Tat. After the review of the fusion design to use the valid reporter proteins as the soluble carrier, three proteins of interest were expressed with and without the soluble carriers. This fusion strategy did not extend Tat acceptance. Overall, this project confirmed the difficulty to export a recombinant protein via the Tat pathway. Additionally, CyDisCo was demonstrated to improve expression of recombinant proteins but did not form native disulphide bonds. However, this project revealed unexpected export of sfGFP, hGH and FABP4 including the recombinant proteins fused to hGH without a signal peptide. This unidentified translocation mechanism(s) needs further characterisation which can lead to the discovery of a new export pathway(s) and may highlight a promising alternative way to target proteins of interest to the periplasm

Bibliografía

Contiene las reseñas de algunas de las obras que recibió la Biblioteca de la Universidad Católica Bolivariana. La ultima obra del profesor J. M. Yepes / Jesús Antonio Hoyos; La teoría de Frankestein en el derecho internacional privado / Alfredo Cock A.; Mi gente por Efe Gómez / José Mejía Mejía; Historia de Colombia por Julio César García / Emilio Robledo; Régimen legal de aguas en Colombia por V. Botero Isaza / G. Jaramillo Btos; Intorni Agli Escritti e Discorsi di Mussolini por Carlos Miró-Quesada Laos / Abel Naranjo Villegas; Maximo Gomez, el generalismo por B. Souza / Gabriel Henao Mejía; Páginas desconocidas de don Juan Montalvo / Jorge Luis Arango J

Notas

En esta sección se publican los siguientes temas: Lógica, fenomenología y formulismo jurídico / Luis E. Nieto Arteta; Vida interior / Alfonso Francisco Ramírez; La crisis contemporánea / José de la Riva Agüero

MACHADO DE ASSIS E O MUNDO DESAGREGADO: UMA LEITURA DE DOM CASMURRO

Este artigo tem por objetivo detectar elementos que ajudem a entender o romance Dom Casmurro a partir da abordagem de situações que difiram da expectativa contida no projeto literário brasileiro da segunda metade do século XIX. No ambiente limitado ao Rio de Janeiro, esta obra supera a descrição referente a um processo mimético de feição local para aprofundar o aspecto psicológico e os dramas da condição humana. Diante disso, buscamos do mesmo modo detectar a relação que se amplia do âmbito local e do conflito familiar para a universalidade das relações que dizem respeito à crise social brasileira no contexto de transformações políticas que têm efeito na passagem entre os séculos XIX e XX. DOI: https://doi.org/10.47295/mren.v7i2.160