Page 33 - Advances in Textile Biotechnology
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12     Advances in textile biotechnology































                                                      Ser264
                                   Val209

                                    Tyr156
                                             Thr181
                                                       Phe190








                     1.2  A model structure of calcium independent α-amylase–Termamyl
                       TM
                     LC  representing the fi ve single substitutions His156Tyr, Ala181Thr,
                     Asn190Phe, Ala209Val and Gln264Ser.

              (Khemakhem et al., 2009). The same strategy of methionine replacement
              by non-oxidizable amino acids was followed and the mutant  AmyUS-
              100ΔIG/ Met197Ala was created by substituting methionine 197 to alanine.
              The mutant α-amylase was found to be very stable in the presence of solid
              detergents and, in some instances, the activity was increased by 10–50%
              after incubation of the enzyme at 40 °C with Ariel, Skip, Dixan, Det, NewDet,
              Nadhif and OMO. These studies indicate that this enzyme is an important
              candidate for potential application in detergent industry (Khemakhem
              et al., 2009).




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