3.4.16.6 5 7 wild-type enzyme 647241 3.4.16.6 5.5 - - 731176 3.4.16.6 5.5 6 - 647234 3.4.16.6 5.6 - - 667510 3.4.16.6 5.6 - and 6.5-7.0. Activity maximum at pH 5.6 is due to activity of domain II, at pH 6.5-7.0 due to domain I 667510 3.4.16.6 5.6 - domain 1B 647241 3.4.16.6 6 - - 647238 3.4.16.6 6.3 - activity assay 698771 3.4.16.6 6.5 7 and 5.6. Activity maximum at pH 5.6 is due to activity of domain II, at pH 6.5-7.0 due to domain I 667510 3.4.16.6 7.4 - domain 2 647241