Selective reverse micellar extraction of penicillin acylase from E coli

Abstract

The recovery of penicillin acylase from E coli by a new reverse micellar treatment is described. The results are compared with the cell disruption by ultrasound followed by reverse micellar extraction. The process gave selective extraction of penicillin acylase directly from the periplasmic space of E coli without disrupting the cells. Unlike ultrasonication which breaks open the cells entirely, making subsequent processing dif®cult and expensive, reverse micellar treatment of cells gave a moderate recovery of 60% of enzyme activity in a highly pure form.

Reverse micellar extraction of bromelain from Ananas comosus L. Merryl

“…Anionic surfactants such as AOT, favor forward extraction at pH values lower than the iso-electric point of the protein. 12 In the present study, when experiments were performed at aqueous phase pH lower than 4.2, white precipitate was observed at the aqueous-organic interphase. A similar observation was made by Chang et al 7 for the AOT/isooctane system at lower pH.…”

“…Proteins with hydrophobic surface patches exhibit similar behavior and may be retained in the reverse micellar phase even at unfavorable conditions of pH and/or higher ionic strength. 12 The maximum back extraction efficiency of 38.48% and an activity recovery of 95.93% was obtained at 0.5 mol L −1 KBr. Variation in the extraction efficiency with two different salts (KCl and KBr) at the same concentration indicated the effect of anions on back extraction.…”

Extraction of Bovine Serum Albumin Using Reverse Micelles Formed by Hexadecyl Trimethyl Ammonium Chloride

“…The cationic surfactant CTAC was used to form the reverse micelles, and the inner surfaces of reverse micelles were positively charged. When the initial aqueous pH is higher than the isoelectric point of the BSA that will be negatively charged, the transferring protein into reverse micelles will be observed [23]. The more the number of protein negative charge carried by the greater initial aqueous pH, the stronger the electrostatic attraction between the inner surface of reverse micelle and BSA.…”

Reverse micellar solutions aided permeabilization of baker's yeast

“…We have been investigating reverse micellar solutions (RMSs) to permeabilize microbial cells for selective release of intracellular proteins directly from the cells [22][23][24][25]. Selective permeabilization of Escherichia coli for recovery of periplasmic enzymes such as, penicillin acylase and alkaline phosphatase, using RMSs of sodium di-octyl sulfosuccinate (AOT) in aliphatic hydrocarbons, has been reported previously [22][23][24]. The RMS can be further manipulated for more selective partitioning of the desired enzymes into the reverse micelles.…”

“…Surfactants and organic solvents, the two basic building blocks of reverse micelles, are however, known to individually permeabilize microbial cells [6][7][8][9][10][11][18][19][20][21]. We have been investigating reverse micellar solutions (RMSs) to permeabilize microbial cells for selective release of intracellular proteins directly from the cells [22][23][24][25]. Selective permeabilization of Escherichia coli for recovery of periplasmic enzymes such as, penicillin acylase and alkaline phosphatase, using RMSs of sodium di-octyl sulfosuccinate (AOT) in aliphatic hydrocarbons, has been reported previously [22][23][24].…”