b general method for synthesising ruthenium ii complexes

... cobalt (II) complexes formed with L1-L9 A newly established method for the NMR spectroscopic assignment of Co (II) complexes, and some preliminary studies of combinatorial libraries by mixing two Co (II) ... constant in Hz s Singlet d Doublet t Triplet dd Doublet of doublets ddd Doublet of doublets of doublets dt Doublet of triplets td Triplet of doublets m Multiplet br Broad Mass Spectrometry (MS) ... 3b units, and the structure of the complexes formed from 3a and 3b. 66,68,22,12,88,87 Ligand contains two subunits, two 2,2 -bipyridine units bridged by an oxomethylene unit ( 3b) and one 4,6-bis(2...

Ngày tải lên: 02/07/2014, 13:33

... also because of its direct involvement in substrate binding (Fig 3A ,B) Indeed, as detailed above, Asp291 stabilizes DHAP through interaction with the inhibitor carbonyl group, and is therefore ... C1 (Fig 3B) Such a conformation is compatible with establishment of an aromatic hydrogen bond between Phe297 and the double bonds present in ACMS We carried out a careful comparison between the ... dimeric forms in solution [18] Therefore, the available structural data suggest Fig Ribbon representation of the overall structure of hACMSD The (a ⁄ b) 8 barrel domain is colored in light blue and...

Ngày tải lên: 18/02/2014, 06:20

... remove unbound, excess b subunit The b subunit was purified from E coli BL21 (DE3) carrying pET1 9b( H6bG), as described above for glycerol dehydratase staining for glycerol dehydratase was performed ... respectively Plasmid pUSI2E(bG) was digested with NdeI and BglII Resulting 600-bp NdeI-BglII fragment was inserted into the NdeI-BglII region of pET1 9b to produce pET1 9b( H6bG) A pair of synthetic ... and BglII Resulting 210-bp fragment was ligated with the 1.5-kb HindIII-EcoRV fragment from pUSI2E(GD) and pUSI2E digested with HindIII and BglII to yield pUSI2E(aG) DNA segments encoding the b...

Ngày tải lên: 21/02/2014, 03:20

... et al Structure of Bg7S, a XEGIP-like protein of soybean Structured digital abstract l Bg7S binds to Bg7S by x-ray crystallography (View interaction) l Bg7S binds to Bg7S by cosedimentation in ... disulfide bonds supposedly stabilize the three-dimen- Structure of Bg7S, a XEGIP-like protein of soybean sional structure of Bg7S The Cys209–Cys418 bond seems to be significant for stabilization ... Interestingly, Bg7S seemed to form a dimer at both weakly acidic pH (6.0) and weakly basic pH (8–9) Table DASA in dimer formation The DASA of the AB dimer is defined as [(ASA of A) + (ASA of B) ) (ASA of AB...

Ngày tải lên: 14/03/2014, 23:20

... tetrasaccharide backbone (XXXG) For many years, endo -b- 1,4-glucanases have been considered to be a subgroup of cellulases (EC 3.2.1.4) Recently, however, it has been clarified that some endo -b- 1,4glucanases ... with Xyl side chains and a fourth unbranched Glc residue, and XXGG-type xyloglucans have two consecutive branched backbone residues and two unbranched backbone residues Various microorganisms ... responsible for the exo-activity of OXG-RCBH, and the absence of the loop is associated with endo-activity in XEG Therefore, it is most likely that the endoactivity of XEG is primarily attributable...

Ngày tải lên: 23/03/2014, 05:22

... 2008 FEBS C Michaux et al be partly responsible for the larger flexibility of the cold b- lactamase and for its ability to hydrolyze large substrates Both psychrophilic b- lactamases have fewer ion ... structures have been solved for psychrophilic proteins, probably because their thermolability and flexibility result in handling and crystallization difficulties [26] Analysis of the available 3D structures ... selected because most previous data published for b- lactamases, obtained using the same substrates and techniques, have been recorded at this temperature The range of cephalosporin substrate concentrations...

Ngày tải lên: 23/03/2014, 07:20

... Cytochrome b5 62 is about 10% identical and aligns with an R.M.S.D of 1.73 for 83 residues, Fig 32 A B Figure 32 Structure overlap for the helical bundle of AtCyP38 with (A) PsbQ and (B) cytochrome b5 62 ... helical bundle will become accessible for interaction with the thylakoid trans-membrane phosphatase Phosphatase binding of AtCyP38 inhibits the 111 dephosphorylation process by phosphatase Binding ... the sandwiched region in between This is probably of great significance in its interaction with other proteins A B Helical bundle β-barrel Helical bundle C Helical bundle Active site Figure...

Ngày tải lên: 14/09/2015, 17:50

... salt bridges contribute favorably to protein stability, recent computational and experimental evidence shows that salt bridges can be stabilizing or destabilizing Due to systemic protein flexibility, ... properly, their flexibility may be achieved by repulsive forces between closely placed charged residues The instability caused by the high surface charge density should be somehow balanced Otherwise, ... pairs because for each new pair the burial cost is cut in half: only one additional residue must be desolvated and immobilized (Yip et al, 1995) 2.1.1.6 Metal binding Metals have long been known...

Ngày tải lên: 16/09/2015, 08:31

... in kinetic behaviour between TaLcc1 and rMaL must therefore be attributable to the variations in several residues forming the binding pocket, most likely Asp236, Ala193 and Val428 observed in ... affects both the activity and the stability of the enzyme [40] The Leu559 fi Ala mutation greatly reduced the turnover number for ABTS, whereas the turnover number for the phenolic substrates ... factor contributing to the rate of substrate oxidation (Table 1) The kinetics of substrate oxidation by laccases has also been shown to be pH-dependent [47] At higher pH values, phenolic substrates...

Ngày tải lên: 14/02/2014, 18:20

... Markov Model for nuclear localization signal prediction BMC Bioinformatics 10, 202 27 Valenzuela SM, Martin DK, Por SB, Robbins JM, Warton K, Bootcov MR, Schofield PR, Campbell TJ & Breit SN (1997) ... signals by karyopherin alpha Structure 8, 329–338 22 Fontes MR, Teh T, Jans D, Brinkworth RI & Kobe B (2003) Structural basis for the specificity of bipartite nuclear localization sequence binding by ... depolarization Evidence for auto-inhibitory regulation of NLS binding J Biol Chem 275, 21218–21223 Kobe B (1999) Autoinhibition by an internal nuclear localization signal revealed by the crystal structure...

Ngày tải lên: 14/02/2014, 19:20

... active in its Mn-bound form than in its Fe-bound form (Table 1) We propose two possible explanations for this finding One is related to inhibition of the binding of the superoxide substrate and the ... six-coordinated structure was observed in Fe-bound ApeSOD, but not in the Mn-bound form, because the crystal contained neither superoxide substrate, nor anionic inhibitors The answer to this question ... of apo (green), Mn-bound (magenta) and Fe-bound (cyan) ApeSODs are superimposed and shown as a stereo view The metal cofactor of the Mn-bound form is indicated by a ball (B) Tetramer structures...

Ngày tải lên: 14/02/2014, 22:20

... interactions with a substrate molecule Both PhyK structures resemble that of AppA in the substratebound state It therefore seems that PhyK is always kept in a conformation suitable for phytate binding, 1290 ... freedom for the bulky phytate to rotate for further dephosphorylation steps or for alternative substrates to bind to the active site Indeed, PhyK is able to dephosphorylate a number of substrates ... binding by hydrogen bond formation, and its dipole facilitates substrate binding as well The hydrogen bond between the backbone nitrogen atom of Asp291 and the 3phosphate of the substrate is the only...

Ngày tải lên: 16/02/2014, 09:20

... Shkl||Fobs| ) k|Fcalc|| ⁄ Shkl|Fobs| R-factor ¼ ShklTest||Fobs| ) k|Fcalc|| ⁄ ShklTest|Fobs| a 2158 b Free Szabo R, Wu QY, Dickson RB, Netzel-Arnett S, Antalis TM & Bugge TH (2003) Type II transmembrane ... hydrophobic residues, but some polar interactions are also possible, and these can be exploited by the design of specific inhibitors To the west, the pocket is limited by Lys224 side chain The flexibility ... connects both interaction surfaces and could probably harbor a linker peptide between two N-terminal domains In enteropeptidase, a bridge of polar residues separates both interaction surfaces In both...

Ngày tải lên: 19/02/2014, 00:20

... a carboxylate residue also exists, Glu in the case of LpxC (Glu78), Asp in the cases of MshB and BcZBP (Asp14 for BcZBP and Asp15 for MshB) It is believed that this residue could act as a general ... mechanism of BcZBP is probably similar to those proposed for MshB and LpxC This hypothesis was further explored by modeling the binding of substrate (GlcNAc) in the predicted active site of BcZBP (Fig ... length of the substrate However, both the specific substrate of the enzyme and the biochemical pathway in which BcZBP is involved remain to be identified Crystal structure of BcZBP from B cereus The...

Ngày tải lên: 19/02/2014, 00:20

... eglinC (PDB 1sbn [32]) and subtilisin Carlsberg in complex with eglinC (PDB 1cse [33]), ovomucoid turkey inhibitor (OMTKY3; PDB 1r0r [34]) or the double-headed tomato inhibitor II (TI2; PDB 1oyv ... inhibitors Structures of PRK with inhibitors or sub- Fig Stereo plot illustrating inhibitor binding in subtilases The binding loop of chymotrypsin inhibitor II (CI2) in complex with subtilisin BPN ... Calcium binding site Binding of calcium ions in subtilases has been shown to be essential for correct folding and stability [15] A total of four calcium binding sites have been reported for the...

Ngày tải lên: 19/02/2014, 07:20

... shared by members of the subtilisin superfamily, where calcium binding has been shown to be essential for correct folding and structural stability [48,49] Considering the stabilizing effect of binding ... high-resolution dataset was obtained at the BW 7B beamline at EMBL outstation DESY Hamburg Data collection statistics for the synchrotron data, which was used to build the structure of the Vibrio proteinase, ... Coombs JM & Brenchley JE (2000) Approaches for deciphering the structural basis of low temperature enzyme activity Biochim Biophys Acta 1543, 417–433 Narinx E, Baise E & Gerday C (1997) Subtilisin...

Ngày tải lên: 19/02/2014, 16:20

... brucei) are summarized in Table With all mutants, and for both organisms, a decrease in kcat for the forward reaction was observed For T brucei, however, and unlike B stearothermophilus GAPDH, ... the extended/bent conformation of inhibitors inside the active site: (a) substitution of Ser247 in T cruzi gGAPDH by Ala246 in T brucei gGAPDH; (b) different conformations adopted by Thr226/Thr225 ... different behaviour patterns for these inhibitors First, the derivatives with the closest structural homology to the substrate behaved as inhibitors with respect to both substrates (GAP and 1,3-BPGA)...

Ngày tải lên: 20/02/2014, 02:21

... in Zymomonas mobilis pyruvate decarboxylase Biochem J 315, 745–751 34 Killenberg-Jabs, M., Konig, S., Eberhardt, I., Hohmann, S & ¨ Hubner, G (1997) Role of Glu51 for cofactor binding and cata¨ ... from brewer’s yeast Biomed Biochim Acta 47, 9–18 46 Baburina, I., Gao, Y., Hu, Z., Jordan, F., Hohmann, S & Furey, W (1994) Substrate activation of brewers’ yeast pyruvate decarboxylase is abolished ... abolished by mutation of cysteine 221 to serine Biochemistry 33, 5630–5635 47 Baburina, I., Li, H., Bennion, B. , Furey, W & Jordan, F (1998) Interdomain information transfer during substrate activation...

Ngày tải lên: 20/02/2014, 11:20

... [protein data bank (PDB) 3if5] [10], and glutaminases from E coli (PDB 1u60) [5], B subtilis (PDB 1mki, 3brm, 2osu) [5], Geobacillus kaustophilus (PDB 2pby) and human kidney (PDB 3czd) have been determined ... glutaminases from B subtilis (YbgJ) [5], E coli (YbaS) [5], G kaustophilus (PDB 2pby) and humans (PDB 3czd), except for Gln63, for which a glutamate residue is substituted in YbaS The C-a locations ... of glutaminase from B subtilis (YbgJ, Bacillus glutaminase) with covalently bound 5-oxol-norleucine (PDB 3brm) reveals its Ser74 to be the catalytic nucleophile [5] On the basis of their crystal...

Ngày tải lên: 06/03/2014, 09:22

... distant interactions between elements of primary FEBS Journal 272 (2005) 166–179 ª 2004 FEBS structure, and include a hydrogen bond between the backbone carbonyl of Asn263 and the backbone amide of ... maltotriose binding site, formed by the concave surface of four SUPR repeats Close structural similarity can be seen between the first three AB repeats of NlpI and MalT (Fig 7B) However, by the sixth ... products were doubly digested with NcoI and BamHI (New England Biolabs, Beverly, MA, USA), and purified by agarose gel electrophoresis onto dialysis membrane, prior to ligation into doubly digested,...

Ngày tải lên: 07/03/2014, 16:20