Page 41 - Advances in Textile Biotechnology
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20     Advances in textile biotechnology


                               Ala182




                                 Ala184


                     Ala189           Ala81


























                     1.3  A model structure of Fusarium solani pisi cutinase representing
                     the five single substitutions Leu81Ala, Asn84Ala, Leu182Ala, Val184Ala

                     and Leu189Ala.


              biocatalysts used in different processes of textile industry. The use of site-
              directed mutagenesis and directed evolution has rapidly emerged and these
              techniques are the choice for the development and selection of mutated
              enzymes with altered and improved activity, specificity, stability and avail-

              ability. The advantages of site-directed mutagenesis are its high reproduc-
              ibility, technical simplicity and cost-effectiveness measured by
              time-consumption and consumable expenses. However, a lack of available
              structural and biochemical information limits the number of proteins that
              can be re-designed by this approach. On the other hand directed evolution
              can be used to tailor a given enzyme without the need for further structural
              and biochemical data, but, owing to the large number of variants obtained,
              this is a time-consuming and expensive method. In addition, results obtained
              can often not be transferred from one biocatalyst to another even if it is a
              structurally or functionally similar one. The high investment in time and




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