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Book of abstracts of the 2nd Meeting of the Institute for Biotechnology and Bio...

A novel engineering systems approach for bioengineering education : the MIT-Por...

This paper discusses the importance of an engineering systems approach to international bioengineering education and how a new educationalresearch program, the MIT-Portugal Program Bioengineering Systems focus area, aims to develop future global bioengineering leaders. The program, comprising both post-graduate advanced studies and doctoral programs, commences in September 2007. Several other international-coll...

Prediction of retention time of cutinases tagged with hydrophobic peptides in h...

Hydrophobic interaction chromatography (HIC) is an important technique for protein purification, which exploits the separation of proteins based on hydrophobic interactions between the stationary phase ligands and hydrophobic regions on the protein surface. One way of enhancing the purification efficiency by HIC is the addition of short sequences of peptide tags to the target protein by genetic engineering, whi...

Cutinase : a new tool for biomodification of synthetic fibers

This paper describes two methods to monitor esterase hydrolysis at the surface of polyester fibres (PETPolyethylene terephthalate). The hydroxyl groups were determined on the fibre surface by alkaline reaction with a reactive dye (CI Reactive Black 5) and colour intensity was determined using a reflectance spectrophotometer. The terephthalic acid solution formed was also quantified after reaction with peroxide ...

Production of 6-aminopenicillanic acid in aqueous two-phase systems by recombin...

Bioconversion of Penicillin G in PEG 20000-Dextran T 70 aqueous two-phase systems was achieved using the recombinant Escherichia coli A56 (ppA22) with intracellular penicillin acylase as catalyst. The best conversion conditions were attained for: 7%(w/v) substrate (penicillin G), enzyme activity in bottom phase 52 U/ml, pH 7.8, temperature 37°C, reaction time 40 min. Five repeated batches could be performed in ...

Application of surface response analysis to the optimization of penicillin acyl...

Penicillin acylase purification from an Escherichia coli crude extract using PEG 3350 – sodium citrate aqueous two phase systems was optimized. An experimental design was used to evaluate the influence of PEG, sodium citrate and sodium chloride on the purification parameters. A central composite design was defined centred on the previously found conditions for highest purification from an osmotic shock extract....

Stability studies of a recombinant cutinase immobilized to dextran and derivati...

Recombinant cutinase from Fusarium solani pisi was covalently attached to dextran and two derivatized silica supports, Biosil-NH2 and Biosil-Dextran-NH2. Kinetic parameters were determined for all three systems as well as for soluble cutinase. Long-term stability in aqueous media was studied; dextran may have a stabilizing role not only due to the covalent links involved but also in the same way as other polyhy...

Partial purification of penicillin acylase from Escherichia Coli in poly(ethyle...

Studies on the partition and purification of penicillin acylase from osmotic shock extract Escherichia coli were performed in poly (ethylene glycol)- citrate systems. Both partition behavior of the enzyme and total protein are similar to those described in other reports increasing ,with pH and tie-line length and decreasing with PEG molecular weight . However, some selectivity could be attained with PEG ...

Comparative studies of alcoholic fermentations using flocculent and non-floccul...

Optimization study of Escherichia coli TB1 cell disruption for cytochrome b5 re...

The recovery of a recombinant intracellular protein, cytochrome b5, from Escherichia coli TB1 cells was carried out by bead mill disintegration in a discontinuous smallscale instrument. This process was optimized by the use of experimental factorial design. Several parameters were studied: operating time, amount and size of beads, cellular suspension concentration, and presence of toluene and lysozyme. For the ...