Báo cáo khoa học: Probing suggested catalytic domains of glycosyltransferases by site-directed mutagenesis Tobias Hefner and Joachim Stockigt ¨ ppt

... Probing suggested catalytic domains of glycosyltransferases by site-directed mutagenesis Tobias Hefner and Joachim Sto¨ ckigt Lehrstuhl fu ¨ r Pharmazeutische Biologie, ... Escherichia coli is a member of the NRD1b family of glycosyltransferases. This enzyme was used to prove, by site-directed mutagenesis, suggested catalytic domains and reactio...

Ngày tải lên: 17/03/2014, 09:20

... genetics and function of NAT1 and NAT2: role in aromatic amine metabolism and carcinogenesis. Mutat Res 506–507, 65–77. 4 Beland FA (1990) Metabolic activation and DNA adducts of aromatic amines and ... substrates are carcino- gens and drugs, elucidation of the catalytic mechanism of these enzymes would allow a more comprehensive understanding of the origin of substr...

Ngày tải lên: 16/03/2014, 00:20

... the catalytic activity of K49-PLA 2 s was hardly detectable. Cloning and full sequencing of the PLA 2 s Cloning of venom PLA 2 s has been facilitated by PCR using properly designed primers and ... the C-termini of all the K49-PLA 2 s (Fig. 3A and [25,26]). Notably, sequences of Tpu-K49a and Tpu-K49b differed by only two substitutions, i.e. R72 and M110 in Table 1. In...

Ngày tải lên: 07/03/2014, 17:20

... a six-blade b-propeller containing five four-stranded sheets and one five-stranded sheet. Expression and purification of PhyH, PhyH-DI and PhyH-DII PhyH, PhyH-DI and PhyH-DII were each expressed in Escherichia ... V max values and lower K m value of PhyH suggests that PhyH is more catalytically efficient and has a greater affinity for InsP 6 than PhyH-DII. Substrate specificity of...

Ngày tải lên: 14/02/2014, 15:20

... reaction mix consisted of 85 ng of atdA1A2,50ngofatdA3,60ng of atdA4A5,2lLof10· Pfu buffer, 2 lLof10· dNTP (mixture of dATP, dTTP, dGTP, and dCTP, each at a con- centration of 100 mm), 2 U of Pfu Turbo ... deepest and narrowest end of the substrate-binding pocket, and is found next to the facial triad of H204, H209 and D356, which coordi- nates the catalytic mononucl...

Ngày tải lên: 19/02/2014, 02:20

... to the standard protocols. Binding of the naturally cleaved TC fragments to mAbs Expression of TC in yeast and plants was accompanied by partial cleavage of the protein at several sites by some ... immu- nological reactivity by western blotting and identified by N-terminal sequencing. Binding of mAbs to synthetic peptides of TC Two long peptides of 30 residues (P A and...

Ngày tải lên: 20/02/2014, 01:20

... features of the LPO and MPO catalytic cycle, such as the existence of Compound I and Compound II isomers and the identification of their spectroscopic properties. After addressing each of these ... each of these questions, we will propose a new hypothesis that describes an integrated vision of the catalytic mechanism of MPO and LPO. A brief survey of the absorption...

Ngày tải lên: 20/02/2014, 02:21

... stabilized by a network of hydrogen bonds between the side chain of Arg33 and the backbone of Met13 and Arg10 (three hydrogen bonds) and between the side chain of Arg10 and the backbone of Arg33 (one hydrogen ... specificity of ribonuclease A. J. Mol. Biol. 252, 328–336. 4156 J. Ko ¨ ditz et al.(Eur. J. Biochem. 271) Ó FEBS 2004 Probing the unfolding region of rib...

Ngày tải lên: 16/03/2014, 18:20

... using steady-state kinetics and NMR spectroscopic characterization of the cofac- tor pyridoxal 5¢-phosphate and binding of carbohydrate ligands. Purified H334G showed 0.05% and 1.3% of wild-type catalytic center ... Chemical 31 P shifts of the PLP phosphate resonance signal of wild-type enzyme in the absence of ligand (d), in the presence of 20 m M arsenate (s), and in...

Ngày tải lên: 23/03/2014, 07:20

... are spectra of [Co_(D97N- EcMetAP-I)], and traces H and J are spectra of [CoCo(D97N- Ec MetAP-I)]; the insert of H shows the hyperfine region of G expanded. Trace K is the spectrum of [Co_(D97A- ... C TS and C A are the total molar concentrations of metal and enzyme, respectively. The best fit obtained for the k max values at 520, 627 and 685 nm provided a P-value of 1...

Ngày tải lên: 30/03/2014, 02:20