Báo cáo khoa học: Enzymatic investigation of the Staphylococcus aureus type I signal peptidase SpsB – implications for the search for novel antibiotics ppt

... presence of inhibitor, v0is the initial velocityin the absence of inhibitor but with (2%) dimethylsulfoxide. The IC50value was determined by ﬁtting the percentinhibition versus inhibitor concentration ... asantibiotic targets because of their essentiality, the eas-ier accessibility of the catalytic domain for potentialinhibitors as a result of being located on the outer side of the cytoplasmic ... of these amino acids areperturbed by substrate binding [17], highlighting theirsigniﬁcance. In SpsB, it is also likely that one or more of the amino acids immediately preceding the catalyticserine...

Tài liệu Báo cáo khoa học: An investigation of the substrate speciﬁcity of the xyloglucanase Cel74A from Hypocrea jecorina pdf

... in the presence andabsence of 2 mm inhibitor. The inhibitors were not hydro-lyzed in the time course of these experiments (10 min).Docking experimentsDocking of the oligosaccharide XXXG into ... contribution of allfour subsites to ligand binding is reﬂected in the higherdegree of inhibition of activity on XXXG by cello-tetraose (60% decrease in activity) compared to cello-triose ... con-taminating enzyme activities. Nevertheless, this sub-strate mixture is still very useful for the qualitativeanalysis of the degradation pattern, and will bereferred to as XXXGXXXG for simplicity.From...

Báo cáo khoa học: Spectroscopic investigation of the reaction mechanism of CopB-B, the catalytic fragment from an archaeal thermophilic ATP-driven heavy metal transporter potx

... resolvedwithin the manual mixing time. This reversible ligandcompetition shows that the nucleotide portion of the analogue is responsible for the specific interaction with the protein.A titration of the ... freezingotherwise invisible intermediates or investigatingsite-specific mutants.Kinetic process of ATP hydrolysisKinetic modelling requires theoretical values for cata-lytic events as an input, ... F0þEA½Et½F1ð3ÞEquilibrium binding of other nucleotides in the presence of mant-ATP For determination of binding constants of non-fluorescentnucleotides, a series of competition titration experiments[43]...

Báo cáo khoa học: Enzymatic features of the glucose metabolism in tumor cells ppt

... overexpressed in metastatic tumors andspeciﬁc inhibition of TKTL1 mRNA can inhibit cellproliferation in several types of cancer cells [22 1–2 24].However, direct determinations of TK activities intumors ... mutations have hit a set of keyproteins involved in the stabilization of the genomeand the regulation of cell proliferation and apoptosis, the transformation into a malignant cell type is accom-plished. ... 6-phosphate inhibition of HK-2. Thisremarkable difference has led to the suggestion thatHK-1 is the dominant isoform in tissues with high cat-abolic (=glycolytic) activity whereas HK-2 is bettersuited...

Báo cáo khoa học: Enzymatic oxidation of NADP+ to its 4-oxo derivative is a side-reaction displayed only by the adrenodoxin reductase type of ferredoxin-NADP+ reductases potx

... Slight alterations in the posi-tioning of the nicotinamide ring in the active site havebeen observed by comparing the mutant with the wild -type enzyme. The described 0.7 A˚shift of the nicotinamide ... emit blue light by ﬂuorescence [8]. We exclude the formation of the species modiﬁed in position 3 of the nicotinamide ring because of the poor reactivity of thisposition towards nucleophilic ... for 3-carboxamide-4-pyridone adenine dinucleotide phosphate formation inwhich the initial and rate-determining step is the nucleophilic attack of the nicotinamide moiety by an active site water...

Báo cáo khoa học: Enzymatic actions of Pasteurella multocida toxin detected by monoclonal antibodies recognizing the deamidated a subunit of the heterotrimeric GTPase Gq potx

... essential for the activity of the mitogenicPasteurella multocida toxin. Biochemistry 42, 497 1–4 977.19 Pullinger GD, Sowdhamini R & Lax AJ (2001) Locali-zation of functional domains of the mitogenic ... antibodies enabledus to detect PMT-induced deamidation in situ, indicat-ing them to be powerful probes for characterizing the actions of the toxin.ResultsAnalysis of enzymatic actions of ... Q209Eanti-β-actinanti-Gα13anti-Gα11anti-Gαsanti-G i2 WB:Fig. 1. Isolation of GaqQ209E-speciﬁc antibodies. (A) Alignment of amino acid sequences of the switch 2 region in the a subunits of mouseheterotrimeric GTPases...

Báo cáo khoa học: Enzymatic properties of the lactate dehydrogenase enzyme from Plasmodium falciparum pdf

... derivedfrom the cotton seed plant, is a known inhibitor of dehydrogenases. Inhibition of PfLDH by gossypolderivatives has proved parasiticidal in vitro [2] and the search for speciﬁc inhibitors is underway ... raises the possibility that substrate speciﬁcity is different from the LDHs thus far investigated in detail, both eukaryoticand prokaryotic. To investigate this possibility, the activity of the ... prod-uct inhibition matrix is shown in Fig. 2. The inhibition patterns found in these experimentsare summarized in Table 1. They show that an orderedsequential bi-bi system in which NADH binds...

Báo cáo khoa học: Enzymatic control of anhydrobiosis-related accumulation of trehalose in the sleeping chironomid, Polypedilum vanderplanki pdf

... improving the manuscript. This study was supported in part by the Promotion of Basic Research Activities for InnovativeBioscience (PROBRAIN), and by KAKENHI, aGrant-in-Aid for Young Scientists ... metabolismenzymes in P. vanderplanki during desiccation The activities of the enzymes involved in trehalosemetabolism were investigated during the desiccation of P. vanderplanki. As desiccation ... anhydrobiosis. Further investigation is required toanswer these questions.During the induction of dehydration in an anhydro-biotic nematode, A. avenae, lipid is used as the mostlikely carbon...

Tài liệu Báo cáo khoa học: Enzymatic properties of wild-type and active site mutants of chitinase A from Vibrio carchariae, as revealed by HPLC-MS pptx

... Bradford MMA (1976) Rapid and sensitive method for the quantitation of microgram quantities of protein util-izing the principle of protein-dye binding. Anal Biochem72, 24 8–2 54.33 Laemmli UK ... chitinase A.Having established conﬁdence in the validity of the method, we systematically investigated, by using ESIMS, the kinetic properties of chitinase A with pNP-glycosides, chitooligosaccharides, ... retaining mechanism. The enzyme exhibitedendo characteristics, requiring a minimum of two glycosidic bonds for hydrolysis. The kinetics of hydrolysis revealed that chitinase A had greaterafﬁnity...

Báo cáo khoa học: Re-evaluation of intramolecular long-range electron transfer between tyrosine and tryptophan in lysozymes Evidence for the participation of other residues doc

... calculated for the initial oxidation of the proteins above pH 4.5 by the inorganic radicals were quantitative. The estimated overallTyrOÆyields after reaction (2) varied with the protein andcould ... of irradiated solu-tion, for which the amino acid composition of peptideswas determined, were screened for the ﬂuorescence signal obtained when an excitation wavelength of 380 nm is used. The ... proteins. The rate constants differ by a factor of % 8with the protein (Table 1). For all proteins the LRET is not stoichiometric. Inaddition the TyrOÆyield varies with the protein. Theseapparently...

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