The thioredoxin-like fold is a well conserved fold that is present in many families of proteins. One such superfamily of proteins include the GSTs which are involved in phase II detoxification. GSTs primarily catalyse the metabolism of xenobiotics but are also involved in transporting non–substrate ligands and reactive compounds. The GST fold comprises an N-terminal thioredoxin domain and an all alpha helical C-terminal domain and is present in at least 18 classes of proteins. The N-terminal thioredoxin domain is characterised by the βαβαββα topology and can be further divided into two structural motifs, an N-terminal (βαβ) and a C-terminal (αββα) motif. A well conserved hydrophobic network exists between these two motifs and the role of the C-terminal motif is elucidated in this study using class Alpha GST as a model protein. A topologically conserved valine (Val58) and an isoleucine (Ile75) located on β3 and α3, respectively, were mutated to alanine. Secondary and tertiary structural characterisation as well as ligandin function of the mutant enzymes displayed no major structural alteration with respect to the wild-type enzyme. This was confirmed with high resolution crystal structures obtained. Enzymatic activity was maintained indicating that no structural alterations have occured that affects the active site dynamics and the domain interface as a result of the induced mutations. Thermal denaturation studies, however, indicated a slight destabilisation in the enzyme in the case of the valine mutation, but a large destabilisation was witnessed as a result of the isoleucine mutation. This is further observed in denaturant-induced equilibrium studies where the thermodynamic stability of proteins can be determined. Furthermore, as a result of the isoleucine mutation, the enzyme unfolds via a populated intermediate in contrast to the wild-type which globally unfolds via a two-state mechanism with no stable intermediates being populated. Pulse-proteolysis was employed as an additional probe for thermodynamic stability where the enzyme was digested by thermolysin at varying denaturant concentrations. Pulse-proteolysis results were in agreement with the thermal and denaturant-induced stability studies further confirming that the isoleucince substitution causes a large destabilisation. Thus these conserved hydrophobic residues of the thioredoxin C-subdomain play a crucial stabilising role in the GST fold.

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Thesis (Honors)--Liberty University Honors Program, 2007.

Thesis (Honors)--Liberty University Honors Program, 2007. / Includes bibliographical references. Also available through Liberty University's Digital Commons.

Thesis (Honors)--Liberty University Honors Program, 2007. / Includes bibliographical references. Also available through Liberty University's Digital Commons.

Zugl.: Vallendar, Univ., Diss., 2005.

No description available.

Many academic studies in the past have focussed on how to create value for businesses in terms of adding profit to the bottom line through performance, and many argue that adding value for the client is also viewed as a profitable business strategy. This strategy translates as a win-win business relationship since long-term relationships ensure customer loyalty, customer retention and repeat business. In the services sector, it is difficult to quantify the worth or value that a particular service has since services are intangible products. The perception of value of such a service is known as “perceived value” since value recognition rests with the consumer who attempts to quantify the worth of that service. It is generally accepted in the services sector that establishing long-term, mutually beneficial, meaningful business relationships add value for the client and helps them to attach a value to the services that company provides. A company cannot establish such relationships without the help of its employees who represents the face of the organisation and implements the value adding strategy on the organisation’s behalf. Recent studies have begun to address this, examining value creation in business relationships in the context of the sale of tangible goods. The process of value creation for customers in services relationships remains underresearched. Perceived value explains why customers choose one particular service over another, why service companies gain competitive advantage by maintaining genuine longterm customer relationships, and why “the personal touch”, created through emotional attributes such as trust, caring and empathy, adds value from customers’ perspective. This dissertation presents a study of perceived value from the perspective of the customer within the context of the delivery of a credence product in a services relationship model. Using grounded theory methodology; following in-depth interviews with consumers of general insurance, a number of customer-value creation dimensions for businesses have been identified. Parallel interviews with members of staff from the supplier company add a further perspective. This research demonstrates how organisations or suppliers in the services industry can add value when delivering a credence product in a services relationship context. It is believed that an understanding of the value-adding dimensions can be implemented to create opportunities to build value for customers, with commensurate benefits for suppliers. Following analysis of the interviews held with each buyer, a total of six value dimensions are identified in the findings chapter. Each dimension is individually described, discussed, and illustrated with quotations from customers and supplier’s staff. Other issues relating to value arising from the interviews are examined in the discussion chapter. Three areas for further research are proposed in the conclusion.

EVA is the difference between a firm¡¦s net operating profit after taxes and its cost of invested capital. While in EVA calculation, some adjustments on GAAP are made to avoid potential information distortion. This study is to calculate CSC¡¦s EVA using Stern Stewart & Co.¡¦s approach and to discuss its information contents. The conclusions of this study are presented as follows¡G 1.For CSC, EVA is better than RI and traditional accounting measures of EPS and ROE in explaining stock prices and MVA. 2.The superiority of EVA to RI in explaining stock prices and MVA means that equity equivalent reserve adjustments are needed for calculating EVA. 3.EVA explains share prices and MVA better after CSC privatized, but the sensitivity of share prices and MVA response to EVA has decreased. 4.By stepwise regression tests, contemporary share prices are best explained by lagged EVA. Contemporary EVA cannot predict future share prices. Implication of this study: CSC¡¦s EVA measure has higher correlation with its share prices and MVA, EVA results would be reflected to share prices and MVA. Therefore, investment evaluation, performance appraisal and bonus plan by EVA-based are suitable for CSC and its subsidiaries. Using plenty surplus cash to purchase back shares for reducing capital stocks is the most efficient way for CSC to increase EVA. Disclosing EVA related information may improve company transparence and therefore enhance share prices and shareholders¡¦ wealth.

No description available.