In recent years, enzymes have become widely used as the additives in laundry products for
reducing the energy consumption and satisfying the customer-expected cleaning effect.
Boosting the stability of these enzymes has become a crucial task in both industry and
laboratory. Subtilisin savinase, as an enzyme product from Novozymes A/S, has these types
of needs as well, since it is usually subjected to the auto-proteolysis issues in the aqueous
solution.
The overall purpose of this project is to integratively characterize the structural properties and
conformational dynamics in savinase by multiple experimental techniques. The results from
these studies can indicate the structural stability of savinase. In addition, the work in this
thesis will deposit several structural datasets that are derived from a variety of
characterization techniques (including x-ray crystallography, hydrogen-deuterium exchange
by mass spectrometry and solution nuclear magnetic resonance spectroscopy), therefore
offering a rich source of structural information for the future rational design of savinase.
The thesis begins with the background knowledge of enzyme stability. In the subsequent
chapter, the background of the targeted enzyme for these structural studies, savinase, is
introduced. Chapter 3 briefly introduces the experimental techniques for studying the
structural insights and conformational fluctuations of savinase, including x-ray
crystallography, hydrogen-deuterium exchange mass spectrometry (HDX-MS), and solution
nuclear magnetic resonance (NMR) spectroscopy. In the following chapter of the results, I
described all the results of x-ray crystallographic, HDX-MS, and solution NMR studies. In
the end, the conclusions and the future perspectives are addressed, majorly focus on the
structural stability of savinase. Several relevant appendices are attached with this thesis.