Enzymes structure-function correlation

Eppler et al. [103] viewed these results as having a potential relationship to salt-activated enzyme preparations, particularly in relation to the mobility of enzyme-bound water. Specifically, the authors examined both water mobility [as measured by T2-derived correlation times, (tc)D20] and NaF-activated enzyme activity and observed a linear relationship. This suggests that the salt-activated enzymes contain a more mobile water population than salt-free enzymes, which facilitates a more aqueous-like local environment and dramatically increases enzyme activity through increased flexibility. Therefore, enzyme activation appears to correlate with the properties of enzyme-associated water. Once again, the physicochemical properties of water dictate enzyme structure, function, and dynamics. Hence, salt activation has proven to be a useful technique in activating enzymes for use in organic solvents and has provided a quantitative tool to better understand the role of water in enzymatic catalysis in dehydrated media. 

Hempel J, Kaiser R, Jdmvall H. Mitochondrial aldehyde dehydrogenase from human liver primary structure, differences in relation to the cytosolic enzyme and functional correlations. Eur J Biochem 1985 153 13-28. 

Solomon El, Brunold TC, Davis MI, et al. Geometric and electronic structure/function correlations in non-heme iron enzymes. Chern Rev 100 235-349,2000. 

The properties of superoxide dismutases (SOD s) have been extensively reviewed . Currently, it seems attractive to work on the biological activity of superoxide dismutases, whereas the chemical aspects are sometimes disregarded. However, devoid of a founded knowledge of the biophysical parameters of these enzymes, the catalytic action of the superoxide dismutases could never have been understood. Thus, a solid structure function correlation is essential. 

Shurki, A., Warshel, A. (2003). Structure/function correlations of enzymes using MM, QM/MM and related approaches methods, concepts, Pitfalls and current progress. In V. Dagett (Ed.)> Protein simulations, Adv. Protein Chem. (Vol. 66, p. 249). San Diego Academic. 

Once the primary structure-function correlates of the well-characterized members of the enolase superfamily were elucidated, that information could be used to understand other superfamily members for which much less information was available. Two examples given below show the power of this technique for prediction of function from unknown reading frames and for extending the understanding of the function and mechanism of enzymes that have been incompletely characterized. The use of superfamily analysis for limited characterization of proteins of unknown function is also illustrated. 

I. B. Vipond and S. E. Halford, Molec. Microbiol., 9, 225 (1993). Structure-Function Correlation for the EcoRV Restriction Enzyme From Non-Specific Binding to Specific DNA Cleavage. 

The increase in levels of tissue CAT is compatible with previous results which showed that LLLT induced an increase in CAT activity of irradiated isolated cardio-myocytes compared to controls. It was suggested that laser therapy efficacy in chronic wounds and ulcers can be attributed to the activation of CAT in tissue fluids [62]. He-Ne laser has been shown to cause photoactivation and structural modifications of catalase enzymes that positively correlated with its functional properties in cell free system [63]. 

The regions of residues 46-49 and of tyrosine 115 must be located in the section of the binding site which interacts with that part of the substrates or inhibitors extending to the 3 -carbon side of the basic structural element, R-dpT. This region is probably of importance in the binding function of the enzyme. More exact correlation of affinity labeling... 

Characterize the structure and dynamics of active sites in enzymes and the correlated motions of secondary and tertiary structures. Measure half-lifetimes of individual steps of electron- and ion-transport during catalytic cycles. Synthesize ligands for metal centers and functionalize inorganic pores to attain enzyme-like activity and selectivity with inorganic-like robustness. 

The wealth of information on eubacterial and eukaryotic citrate synthases, and the correlations of structure, function and taxonomy, have prompted us to extend these studies to the archaebacteria. With the exception of a few methanogens, the enzyme is present in all major groups [46], and thus is a good candidate for comparative enzymology. 

In Chapter 25, Yang and Wen discussed the physicochemical properties of DESs and reviewed their uses as new reaction media for biocatalytic transformation, either as such or as a co-solvent with water. They have introduced a new type of DESs, natural DESs (NADESs), which possess an enormous potential for applications due to their non-toxicity, sustainability, and friendliness to the environment. The advantages of using DESs over the conventional ILs are low cost, easy preparation with high piuity and biodegradability, and low toxicity. More studies of DES on biocatalysis with the following perspectives have been suggested, (i) correlation between the stmctme and composition of a DES and its physicochemical properties (ii) correlation between the structure of a DES and its interaction with an enzyme and (iii) correlation between the DES structure and enzyme function. 

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