Báo cáo khoa học: Mutational analysis of substrate recognition by human arginase type I ) agmatinase activity of the N130D variant pot

... further corro- borate the existence of active site differences between the isoenzymic forms of human arginase. In fact, whereas partial arginase activity is retained by the N130D variant of arginase ... ligands for the a-carb- oxylate group of the substrate arginine. As this is the Fig. 4. Effects of dialysis against EDTA on the catalytic activity o...

Ngày tải lên: 16/03/2014, 12:20

... proteolysis is involved. PAI-1 belongs to the serine protease inhibitor (serpin) family whose antiproteolytic activity is governed by their structural flexibility. In the active serpin conformation, the reactive ... terms of specific inhibitory activity (Table 2). Thus, the introduced mutations did not compromise the correct folding of PAI-1 in its active conformation. Com...

Ngày tải lên: 20/02/2014, 11:20

... structures of the maltose-maltodextrin-binding protein of the thermo- acidophilic bacterium Alicyclobacillus acidocaldarius provide insight into acid stability of proteins. J Mol Biol 335, 261–274. 23 ... C-domain part of the sugar-binding site. The C-domain part consists of four regions designated region C -I (residues 170–17 7), region C-II (residues 227–23 2), regio...

Ngày tải lên: 19/02/2014, 00:20

... Federico II, Italy 2 CEINGE Biotecnologie avanzate, Napoli, Italy 3 Dipartimento di Chimica Organica e Biochimica, Universita ` di Napoli Federico II, Italy 4 Dipartimento di Chimica, Universita ` di ... ⁄ substrate ratio, temperature and pH conditions in order to maintain the stability of the complex and drive the hydrolysis towards the regions of the protein not involved in...

Ngày tải lên: 06/03/2014, 00:21

... l M , respectively. Therefore, the enzyme exhibited significantly stronger inhibition by aromatic organic acids than by small aliphatic organic acids. n-Butyric acid is known not only as a competitive inhibitor ... greater, compared the wild -type enzyme (Table 3). Discussion Substrate specificity comparison with other NHases The kinetic parameters of P. thermophila NHase, wit...

Ngày tải lên: 16/03/2014, 16:20

... this role, explaining the residual activity of the D215N mutant. The possibility to interact is obviously lost in the D215A mutant which in fact is one of the least active mutants described in ... catalysis in family 18 chitinases proceeds via formation of an oxazolinium ion. This intermediate is formed upon nucleophilic attack of the carbonyl oxygen of the N-acetyl...

Ngày tải lên: 07/03/2014, 14:20

... University of Insubria, Varese, Italy 4 Department of Neuroscience, University of Torino, Italy Introduction Parkinson’s disease (PD) is a sporadic neurodegenera- tive disorder of unknown etiology ... significantly affected by a-synuclein overexpression (Fig. S 2). Discussion Proteins differentially expressed in this model are individually linked to PD Most of the identified pr...

Ngày tải lên: 15/02/2014, 01:20

... 0, inhibition is competitive; if a = 1, inhibition is noncompetitive; if a > 1, inhibition is mixed. If the ternary complex ESL is nonproductive (b = 0), there is linear mixed inhibition. If ... parabolic competitive inhibition. Parabolic inhibition suggests that the binding of more than one benzalkonium con- tributes to the inhibition (Fig. 4). The multiplicity of cation b...

Ngày tải lên: 18/02/2014, 17:20

... DCMU would inhibit completely the activity of PSII by preventing the reduction of the PQ pool [21,22], drastically channging the typical FI trace of thylakoids by eliminating the J–P rise [4,24]. ... reactions involved in the reduction of the acceptor side of PSII [33]. In this simulated model, the J I phase was calculated to be simultaneous with the initial...

Ngày tải lên: 19/02/2014, 05:20

... the matrix and their ionization properties, will not differ significantly. Thus, the relative intensities of the different peaks constitute a fair estimate of the fraction of each species in a particular ... group of the Lys9 side-chain, which simultaneously interacts with the main phosphate of the substrate [32]. The closer positioning of the N-terminus to the...

Ngày tải lên: 19/02/2014, 12:20