DHFR protein

The catalytic activities of the fortified wheat germ cell-free systems supplemented with each fraction were investigated (Fig. 2). As shown in Fig. 2, only 0 - 40 % ammonium sulfate fraction showed an enhancement in DHFR protein synthesis. This enhancement of protein experimental results and the fact that the various eukaryotic initiation factors are contained in synthesis was also confirmed by SDS-PAGE and autoradiography (Fig. 3). From the above 0-40 % ammonium sulfate fraction [5, 6], it can be concluded that the amount of initiation factors in a conventionally prepared wheat germ cell-fi extract is deficient for the translation of DHFR with internal ribosome entry site. Therefore, it needs to supplement a wheat germ cell-free extract with the fraction containing the limited initiation factors for the efficient protein translation, and this fortified cell-free system can be easily made by simple... 

Two more models related to the GB formalism should be mentioned as they may provide some insights for future development. It was shown that a somewhat similar expression of the solvation energy can be obtained from the boundary element formalism [60]. The method was applied successfully to the docking of a variety of ligands to the DHFR protein [61]. Another approach for the estimation of the fGB function was reported recently [62]. The method is based on the screened Coulomb potential and seems to reproduce the structure of small peptides correctly [63]. 

DHFR protein molecule. The protein fold through its complex vibrational modes apparently may couple some set of motions to a promotional vibration that fosters passage of the reactive ternary complex over the activation barrier. 

Fig. 3. Autoradiograph of SDS-PAGE of in vitro translated dihydrofolate reductase (DHFR) in the wheat germ cell-free protein synthesis systems with (n) 4 pi of ribosome fiaction, (III) 4 pi of 0 -40 % ammonium sulfate fraction, or (IV) 4 pi of 40 - 60% ammonium sulfate fraction, respectively. Lane I is control dihydrofolate reductase produced in the normal wheat germ cell-free protein synthesis system.

Protein synthesis and selective inhibition 5.3 DHFR inhibitors... 

Folic acid antagonist inhibits dihydrofolate reductase (DHFR) blocks reduction of folate to tetrahydrofolate inhibits de novo purine synthesis results in arrest of DNA, RNA, and protein synthesis... 

Figure 5.10. Protein complementation assay using murine DHFR. The F[l,2] and F[3] fragments are each fused to the homodimerizing GCN4 leucine zipper protein. A. Transformation of both Z-F[l,2] and Z-F[3] constructs results in reconstituted DHFR and growth of E. coh on agar plates containing trimethoprim. B. Transformation of Z-F[l,2] or Z-F[3] alone does not result in trimethoprim resistant E. coli cells. Figure adapted from Pelletier et al. (1998).

KarmaData contains information which the user enters, e.g., QSAR equations, congener set, as well as information about previously studied enzyme-ligand binding complexes. KarmaData contains several classes and subclasses. For example, in KarmaData, there is a class called proteins, a subclass in proteins called dehydrogenase, a particular member of dehydrogenase c led DHFR, and a specific instance of DHFR called chicken (vide ir a). Chicken DHFR contains those attributes which are specific to itself, and inherits properties from units DHFR, dehydrogenase, and proteins. 

Fig. 13 CORCEMA-ST optimized structure of bovine DHFR/TMP complex. Protein residues within the binding pocket are aqua blue and ligand residues light purple. The hydrogens were omitted for clarity. Reprinted with permission from [75] 2005, American Chemical Society...

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