Proteases, genetic engineering

In 1989, two enzymes based on genetic engineering techniques were introduced, ie, a cloned alkaline protease (IBIS) and a protein engineered Subtihsin Novo (Genencor, California). Lipase and ceUulase types of detergent enzymes have also begun to appear. 

Some recent approaches to orientated immobilization exploited methods of genetic engineering to introduce suitable binding site like a cysteine residue [101]. Mansfeld and Ulbrich-Hofmann introduced cysteine on a thermolysinelike neutral protease from Bacillus stearothermophilus [114]. This approach is especially interesting since it allows the introduction of cystein residues in different positions of the protein molecule and therefore enables one to study the effects of molecule orientation on its biological activity [115]. More information about the oriented immobilization can be found in recent reviews of Turkova [101,110]. 

Two genetically engineered variants of human t-PA have better pharmacological properties than alteplase. Reteplase (Retavase) contains only the peptide domains required for hbrin binding and protease activity. These... 

Apart from proteases, cutinases and lipases were demonstrated to hydrolyse PA. Hydrolysis of PA with a lipase (not further specified) was confirmed by using FTIR analysis and dye-binding assays [32]. Several reports have assessed the potential of cutinases for PA functionalisation, and a fungal cutinase from F. solani was successfully genetically engineered towards higher activity on a PA oligomer and PA [23-25]. 

E. Liberation of Biologically Functional Peptides IV Genetic Engineering of Milk Proteins and Proteases... 

Birk, Y, Ed., Plant Protease Inhibitors Significance in Nutrition, Plant Protection, Cancer Prevention, and Genetic Engineering, Springer, Berhn, 2003. 

Apart from proteases and amidases, a cutinase from Fusarium solani has been shown to hydrolyze polyamides and genetic engineering was successfully used to achieve higher activity [88-90], Interestingly, the same cutinase was also able to hydrolyze PET. 

An area at the forefront of commercial applications of genetic engineering is the production of enzymes from genetically modified organisms. The milkclotting protease, chymosin, has been the first food ingredient produced via recombinant DNA techniques to be cleared for food use (21). The use of designed enzymes adjusted to specific process requirements will also provide new possibilities in the field of flavors. 

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