Liquid-liquid extraction of a Schistosoma mansoni recombinant protein from an Escherichia coli extract in aqueous two-phase system

Abstract

This work describes the partition of a Schistosoma mansoni tegumental antigen produced by a recombinant Escherichia coli strain using an aqueous two-phase system composed of polyethylene glycol (PEG) and potassium phosphate. The effects of the polymer molecular weight, tie line length and pH on antigen partitioning were investigated. The detection of the antigen in both phases were determined by ELISA. The system composed of PEG 3550 (19.7% w/w) and potassium phosphate (17.7% w/w) led to a yield of 59% and an antigen puri®cation factor of 3 in the PEG-rich phase. It was observed that the antigen partition in ATPS was strongly affected by the pH value and tie line length. In addition, it was possible in a single step, to remove the cell debris, that precipitated at the interface of the system.

Extraction of amylase from fermentation broth in poly (Ethylene Glycol) salt aqueous two-phase system

“…In order to perform large-scale purification of enzymes and proteins an efficient downstream processing technique amenable to preserve biological activity is needed (Tanuja et al 1997). Extraction in aqueous two-phase system (ATPS) is a suitable method for the first step of a separation procedure removing some contaminants in a simple and economic process (Chaves et al 2000;Hatti-Kual 1996;Kula et al 1982). Aqueous twophase systems are based on water-soluble polymers and salts and/or two different watersoluble polymers.…”

“…This separation procedure, i.e. partition, is influenced by phase system parameters, such as the molecular weight of the polymer, pH, type and concentration of phase forming components (Chaves et al 2000). The PEG/salt system is suitable for downstream processing of amylase, due to its high capacity biocompatibility and low costs.…”

"Extração da pró-toxina épsilon e de uma protease a partir de ´Clostridium perfringens´ em sistemas de duas fases aquosas utilizando PEG/citrato"

“…O ELISA é um método imunoenzimático que permite quantificar os anticorpos ou antígenos presentes em amostras biológicas. O seu princípio básico é a imobilização de um dos reagentes numa fase sólida, enquanto o outro reagente pode ser ligado a uma enzima, com a preservação da atividade biológica dos reagentes (antígenos e anticorpos) (Chaves et al, 2000).…”