characterization of the reservoir rock

... the inner part of the membranes As shown in Figure 4e, many big aggregates appear in the middle part of the PVDF-PS membrane The hydrophobic property of PS polymer promoted the formation of these ... Thermal analysis of the PVDF-SPS composite membrane The TG analysis curve is presented in Figure for the investigation of the thermal stability of the PVDF membrane, PVDF-PS membrane, and the PVDF-SPS ... decomposes The swelling is due to the degradation of the cross-linking structure of the membrane in the H2O2 solution [33] The decomposition rate is larger than the swelling effect after 60 h The result

Ngày tải lên: 05/09/2013, 16:11

... organs of members of the small plant family Caricaceae [1]. The two economically most important genera of this family are the commonly grown tropical species Carica papaya and the group of highland ... higher concentration of enzymes in the latex of Vas- concellea fruits, but in addition also results from the presence of other cysteine proteinases or isoforms. In contrast to the cysteine proteinases ... proteinases or isoforms in the latex. To investigate these two hypotheses, the protein concentration per milligram of dried latex, as well as the amidase activity per milligram of protein, was measured

Ngày tải lên: 07/03/2014, 11:20

... similar pattern of five bands, one of which was also more intensive than the others. Thus, the different intensity of the bands may be the result of a different copy number of the genes in the hybridizing ... otherwise, the efficiency of the amplification will be lower than that of the considered variants, and this will result in an overestimation of the amount of genomic DNA containing one copy of the ... the biological role of the sequence (Fig. 2). The sequences of the catalytic A-chain of the MLp toxins were found to differ. However, the amino acids forming the catalytically active center of

Ngày tải lên: 07/03/2014, 15:20

... to all of the tRNA binding sites on the ribosome (i.e. A, P and E sites) [13,14]. As expected, the addi- tion of SF to the system resulted in pppGpp synthesis (Fig. 2). The speed of synthesis, ... template, the activity of the enzyme is similar to that in the absence of tRNA. This is not surprising because the template is needed to position tRNAs on the ribosome [26]. The activity of the poly(U)-dependent ... function of time. The input of radioactive GTP in the reactions is indicated by the asterisk. See Experimental procedures for more details. Table 1. Characterization of SF-activity in the poly(U)-dependent system.

Ngày tải lên: 07/03/2014, 16:20

... structure. The confor- mations of residues 8–9 are ill defined in the peptides. Thus, the introduction of a prolinoamino acid in the C-terminal tail of SP does not affect the overall structure of the ... log(DR–1)–log[B].DRisthedose-ratio[A]¢/[A] where [A]¢ is the concentration of agonist A, in the presence of the antagonist B, which is equiactive to [A], the concentration of agonist in the absence of antagonist. ... in methanol [35]. The random coil value of Pro was used for the different prolinoamino acids. Therefore, the CSDs of P 3 Leu10 depend primarily on the chemical modification of the pyrrolidine ring and

Ngày tải lên: 08/03/2014, 02:21

... mapping experiments. The last exon is composed of a coding sequence of 193 bp and of an untranslated region of at least 131 bp. The size of the 24 introns ranges from 79 bp to about 16 kb. The size of the largest ... transcript of a predicted size of  13 kb. Both human MUC4 and mouse Muc4 genes are virtually identical in terms of the class of introns, the exon number and size of exons. The sizes of the 24 mouse ... represents the codon for initiation of translation and, therefore, codes for the N-terminus of the protein. This fragment contains a 105-bp fragment of 5¢ untranslated sequence upstream of the putative

Ngày tải lên: 08/03/2014, 23:20

... vector. The nucleotides are numbered from the translation start site (ATG). The effect of the wild-type and mutants was measured as the mean of the firefly luciferase levels nor- malized by the Renilla ... conjunction with the luciferase gene in pGL3- basic vector. The nucleotides are numbered from the translation start site. The effect of the wild-type and mutants was measured as the mean of the firefly ... purpose, we tested 12 of the 14 sequence vari- ants located within the 1418 bp of the 5¢ flanking region of APOH for allele-specific regulatory effects on the expression of the dual luciferase reporter

Ngày tải lên: 15/03/2014, 10:20

... postulated in the experiment of Fig. 2. Mutation of the essential amino acid Ser237 Establishment of the E. coli expression system of GluV8 enabled the roles of certain amino acids com- prising the protease ... heat in the presence of SDS. Role of N-terminal Val69 in processing of the GluV8 proform Finally, the role of N-terminal Val69 of mature GluV8 was investigated. It has been proposed that the a-amino group ... N-termini of the processed forms were not the 69th substituted amino acids, but entirely Ile70. These results show that thermolysin attacks the Xaa69-Ile70 bond of the mutant rather than the Ser-Xaa69 (Xaa

Ngày tải lên: 16/03/2014, 06:20

... quality of the end product (softer texture of ice cream, faster ripening of cheese, etc.) and also lessens the problem of lactose intolerance, which is prevalent in more than half of the world’s ... All these positions are located at the surface of the jelly roll domain of Bga1 and thus most probably are glycosylated in vivo. To further substantiate these findings, in gel digestion of the ... that of d-galactose. The degree of transglycosylation was dependent on the concentration of the substrate, as also found in other studies [12,13]. Activity of Bga1 on polymeric substrates The

Ngày tải lên: 16/03/2014, 11:20

... have the same structure as the original monomer, with the exception of the ‘hinge loop’ that connects the tail with the rest of the structure (often referred to as the ‘body’). The interface between ... from the rest of the protein during thermal denaturation would also require a substantial unfolding of the whole protein and thus dissociation of the N-terminal domain from the rest of the protein ... Glu103 residues of one subunit and Arg104 residues of the other [8]. In this dimer, the rel- ative positions of the two subunits would prepare the molecule for the swapping of the N-terminal domain while,

Ngày tải lên: 16/03/2014, 13:20

... properties of SPC4. The absorption spectrum of purified SPC4 was recorded in 50 m M sodium acetate pH 5. The inset shows the spectrum of the extract- ed heme. (B) MALDI-TOF-MS analysis of SPC4 heme. Characterization ... (T m ¼ 74 °C) [37]. In the presence of Ca 2+ , the T m of SPC4 is near that of soybean peroxidase, which is one of the most stable plant peroxidases with a T m of 90 °Cin the presence of calcium [38]. In ... is needed to establish the proximal calcium binding site. The binding of Ca 2+ has been proposed to change the electronic properties of the heme iron or the topology of the heme vicinity and might

Ngày tải lên: 16/03/2014, 13:20

... Accord- ing to the model, the N-1 atom of His79 is located 2.4 A ˚ from the 8a C atom of the isoalloxazine ring in FAD, and the S atom of Cys138 is located 1.8 A ˚ from the C-6 atom. The distance ... [14]. Furthermore, we consider the hypso- chromic shift of the first maximum of the difference spectrum to 360 nm a unique feature of the 6-S-cystei- nyl, 8a-N1-histidyl FAD. Together, these observations support ... with the modelling data of the FAD surroundings (Fig. 6), leads to the conclusion that His79 is bound at the N-1 position of histidine. The higher pK a value is attributed to the influence of the

Ngày tải lên: 16/03/2014, 14:20

... NMR characterization of the Nogo-A functional domains (Eur J Biochem 271) 3513 Fig Schematic representation of the domain organization of the human Nogo-A protein (A) The domain organization of ... in an aqueous environment The NMR structure of Nogo-40 was therefore determined in the presence of the helix-stabilizing solvent trifluoroethanol The solution structure of Nogo-40 revealed two well-defined ... Song1,2 Department of Biological Sciences and 2Department of Biochemistry, National University of Singapore, Singapore The recent discovery of the Nogo family of myelin inhibitors and the Nogo-66 receptor

Ngày tải lên: 16/03/2014, 16:20

... the assay, in contrast to that of the mammalian d-PGAM that was enhanced 300% by the addition of its cofactor. The increase ofthemutaseactivityoftheLeishmania fraction might be explained by the ... Figure 1A shows the activity upon the addition of 3PGA in the presence of 0.55 U of ENO and a sample of each cell fraction. Under these conditions, the main reaction monitored should be the PGAM- and ... determine the influence of the presence of metal ions on the accessi- bility of the active-site histidines. Table 2 shows the results for the different EDTA-treated enzyme samples. Clearly, the histidines

Ngày tải lên: 16/03/2014, 16:20

... studies and the recent release of a fully annotated map of the Plasmodium falciparum genome have shown the presence of a complete battery of enzymes of the Embden–Meyerhof– Parnas pathway of glycolysis ... buffers (Fig 4) The optimum pH for oxidation of malate in the presence of NAD was 10.2 and for the reduction of OAA using NADH as the cofactor it was 7.0 Further kinetic characterization of enzyme ... considering the sequence identity of only 26% between the two enzymes On the other hand the structure appears to be similar to that of Pf LDH with a rmsd of 0.8 between the Ca atoms (Fig 5) Both the cofactor

Ngày tải lên: 16/03/2014, 18:20

... about fivefold over the case of the empty vector control or the case of the GAL4–DBD–MET with ethanol. This activation by JH III can also be described as about twofold when compared to the case of GAL4–DBD with ... lm. Among these, JH III, which is one of the native JHs of Drosophila, was found to be the most effective over the range of concentrations tested. Of note is that JH III was conspicuously active in the ... (Fig. 6). In both cases, the fluorescence of the fusion proteins was seen in the nucleus. In these experiments the use of cultured cells allows for com- plete depletion of JH. These observations are

Ngày tải lên: 16/03/2014, 18:20

... to the N-terminus of the protein. An A-ring endo-vinyl group of the chromophore is abso- lutely required for this covalent attachment [15,21]. Our data support the proposal that the lack of the conserved ... [7,16]. The covalent binding of biliverdin IXa was confirmed by zinc-induced red fluorescence (Fig. 3C). The form initially synthesized after the addition of biliverdin IXa to apo-BphP in the dark is the ... therefore the site and kind of attachment of the bilin chromophore in the bacterial phytochromes is controversial [1,21,22]. To investigate whether the chromophore is attached via a thioether linkage

Ngày tải lên: 16/03/2014, 18:20

... cm )1 ) of the Fe(II)–CO complex of isolated PAS-B in the low (left) and high (right) fre- quency regions. The lower spectra are of the Fe(II)– 12 C 16 O complexes, the middle spectra are of the ... cm )1 , and the presence of a band at 1467 cm )1 indicated partial photodissociation of CO from heme. The CO-isotope dependences of the resonance Raman spectra of the Fe(II)–CO complex of PAS-B are ... discussed in the last part of Results. Table 1 summarizes the spectral maxima of the wild-type and His mutant PAS-B complexes. The Soret peaks of the Fe(III) and Fe(II) complexes of wild-type

Ngày tải lên: 16/03/2014, 22:20

... Four regions of the sequence of RBP at the opening of the barrel make contacts with TTR [32]. The residues in RBP in three of the regions involved in these contacts are identified in Fig. 6. The protein ... ps through the 160 unbiased MD simulations. These data demonstrate the broadness of the conform- ational space explored in the study. Analysis of the range of RMSD values seen for the MD conformers shows ... a study of the role of the C-terminal region of the RBP sequence which was excluded from the simulations reported here. Comparison with other molten globule states Overall, analysis of the partially

Ngày tải lên: 16/03/2014, 23:20

... understand the relationships among the polymorphs. Heats of solution of the various polymorphs need to be measured, in order to prove the relative order of stabilities for these solid forms. At the ... a wavelength of 1.540600 Å. The X-ray data was collected using an MBraun curved PSD with a chamber depth of 1 cm. The focal radius of the system was 57 mm, and the 5 cm length of the PSD subtended ... samples which were isolated. These results are summarized in Table 4. In many cases the mixture of polymorphs can be accounted for by the addition of the DSC results of the component pure polymorphs....

Ngày tải lên: 14/02/2014, 03:20