Identification of enzymes

Identification of Enzymes of the Ubiquitin-mediated Proteolytic System... 

Figure 2. Efficiency of an rDNA approach to enzyme commercialization. Areas in boxes refer to the typical times required for Identification, Scale-up and Commercialization. Efficiencies are recognized in Identification of enzymes (protein engineering) and shortened Scale-up times (generic hosts).

Iatsimirskaia E, Tulebaev S, Storozhuk E, et al. Metabolism of rifabutin in human enterocyte and liver microsomes kinetic paramters, identification of enzyme systems, and drug interactions with macrolides and antifungal agents. Clin Pharmacol Ther 1997 61 554-562. 

Chance, B. The identification of enzyme-substrate compounds. In Modern Trends in Physiology and Biochemistry (Woods Hall Lecture dedicated to the Memory of Leonor Michaelis). E.S. Guzman Barron (eds.) pp. 25-46. Academic Press, New York, 1952. 

Significant progress has been made in the identification of enzymes from P. cyclopium which catalyse the various reactions of cyclopenin (124) and cyclopenol (125) biosynthesis.105 One of these is cyclopeptine dehydrogenase which catalyses the interconversion of (122) and (123).105a,1°6 Further research107 has shown that... 

JH can be inactivated by opening of the epoxide ring to a diol 45, or by hydrolysis to the free acid 47, and sometimes further by phosphorylation of the diol (Scheme 5). As the isolation and identification of enzymes involved in hormone synthesis and catabolism advances, a JH diol kinase has been isolated from the tobacco hornworm Manduca sexta that converts JH I diol into the phosphate 48.91 This enzyme is probably the first example of a phosphotransferase directly involved in the catabolism and inactivation of a lipid-soluble hormone. It was much less active in catalysing the phosphorylation of JH II or JH III diols and was inactive with the free JH acids.91... 

The examples provided in this Chapter demonstrate that directed evolution resembles a very useful tool to create enzyme activities hardly accessible by means of rational protein design (Table 14.1). Even if the desired substrate specificity is known from other biocatalysts - e.g. phospholipase A1 activity - the advantage of the directed evolution approach resides in the already achieved functional expression of a particular protein. Thus bottlenecks arising from the identification of enzymes by traditional screening and cultivation methods can be circumvented. In addition, directed evolution can dramatically reduce the time required for the provision of a suitable tailor-made enzyme, also because cloning and functional expression of the biocatalyst has already been achieved. 

As discussed above, not all of the proteins identified by mode-of-action studies employing the SMART approach are suitable drug targets. However, the identification of enzymes of the glycolytic complex by affinity chromatography and their validation by BIAcore analysis finally led to the working hypothesis that Leflimo-... 

Reference given only to original identification of enzyme. 

The chemogenomics approach has not been applied in the identification of lipoamide-, biotin-, and cobalamin-dependent enzymes. Given the stable, covalent bond between lipoamide and biotin with enzymes, only the replacement with inactive cofactor analogs during protein folding can lead to the identification of enzymes associated to loss of function. 

Momen, FI. (1979). Biochemistry of intraerythrocytic parasites. I. Identification of enzymes of parasite origin by starch-gel electrophoresis. Ann. Trap. Med. Parasitol. 73,109-115. 

To understand the dynamics of LPs in vivo, it is necessary to review the enzymes involved in LPA production and degradation. After the identification of the receptors, the identification of enzymes responsible for LP synthesis and degradation has accelerated our understanding of lipid biology (Fig. 10.3). 

Adam, G. C., Sorensen, E. J., Cravatt, B. F. (2002b). Trifunctional chemical probes for the consolidated detection and identification of enzyme activities from complex proteomes. Molecular Cellular Proteomics MCP, 1, 828—835. 

The identification of enzymes selectively expressed by tumor cells and tissues may provide a rich source of new biomarkers and targets for the diagnosis and treatment of cancer. In one such effort, the activity, subcellular distribution, and glycosylation state of members from the SH superfamily of enzymes was quantitatively profiled across a panel of human cancer cell lines [20]. The SHs represent one of the largest and most diverse enzyme classes in higher eukaryotic proteomes, consisting of proteases, lipases, esterases,... 

---