Báo cáo khoa học: Structural and functional consequences of single amino acid substitutions in the pyrimidine base binding pocket of Escherichia coli CMP kinase pdf

... Electron-density map of the dCMP -binding region for the R188M CMP kinase variant. The Fo) Fcomit map calculated for the dCMP–R188M CMP kinase complex in the absence of the dCMP model is green. The contour ... with the amino group and the N3 atom of the cytosine (Fig. 1). This study uses site-directed muta-genesis to further explore the contribution of these amino acids interacting with the pyrimidine ... consequence on binding or phosphorylation of the correspondingNMPs (A37 and T39 in these enzymes are equivalentto S36 in E. coli CMP kinase) .Substitution of R110 with Met in E. coli CMP kin-ase...

Tài liệu Báo cáo khoa học: Structural and functional studies of the human phosphoribosyltransferase domain containing protein 1 docx

... solutions. The ligandbound was interpreted as GMP because the N2 of the base makes a hydrogen bond to a main chain car-bonyl. Binding of a xanthine base from XMP in the same position, would lead to the ... guanine and hypoxanthinebases, respectively, indicating that Asp137 functions asa catalytic base [12]. However, a tight binding of N7 of the purine base and Asp137 was observed in HPRT in complex ... N7 (Fig. 1C). The 2¢OH of the ribose is hydro-gen bonded to the main chain and the side chain of Asp142 (Fig. 1C). Both hydroxyl groups of the riboseare involved in coordinating a putative...

Tài liệu Báo cáo khoa học: Structural and functional studies on a mesophilic stationary phase survival protein (Sur E) from Salmonella typhimurium ppt

... shown indicate the starting and ending residues of the secondary structural elements. (C) The domain-swapped dimer of St SurE. The A and B subunits areshown in green and blue, respectively. The ... determined and con-ﬁrmed by comparison with the S. typhimurium genome. The cloning strategy resulted in 14 additional amino acids from the vector at the N terminus of the expressed protein, includ-ing ... A˚). The other interactions of D234 in Aa SurE correspondto the interactions of D230 in St SurE. A different set of interactions appears to promote a rigid structureleading to domain swapping in...

Tài liệu Báo cáo khoa học: Structural and functional investigations of Ureaplasma parvum UMP kinase – a potential antibacterial drug target ppt

... 168–174are missing; in chain F, residues 1 and 168–175 are missing.All amino acid residues were present in the E chain, and part of the His-tag was observed in the B chain. A few amino acid residues ... Superposition of UpUMPK (green) on top of E. coli UMPK (blue) at the active site. (B) Binding of UMP to E. coli UMPK and the location of amino acid residues in UpUMPK based on the superposition.ABCFig. ... residues are found in disallowed regions in the Ramachandran plot; these are A4, A165, A167, B3, B4 and F165, all of which are found at either the beginning or the end of a chain. The structure has...

Tài liệu Báo cáo khoa học: Structural and functional speciﬁcities of PDGF-C and PDGF-D, the novel members of the platelet-derived growth factors family docx

... candidates.Receptor binding of PDGFs The PDGFs bind to the protein tyrosine kinase receptors PDGF receptor-a and -b. These two recep-tor isoforms dimerize upon binding the PDGFdimer, leading to three ... heparin- binding domain in the C-terminal region of the growthfactor domain but the exact residues responsible for the binding have not been identiﬁed [25]. PDGF-D hasnot been shown to bind ... active [8,10,12]. The CUB domains arebelieved to prevent PDGF-C and -D binding to theirreceptors by structurally blocking receptor -binding res-idues of the growth factor domain. In contrast, tworeports...

Báo cáo khoa học: Structural and functional aspects of unique type IV secretory components in the Helicobacter pylori cag-pathogenicity island potx

... of the moleculeinvolving a-helix A, the nearby loop, the ﬁrst and lastturns of helices E and F, and the C-terminus helices I and J. In addition, there is a lysine-rich N- and C-ter-minus, in ... anti-parallel to the same strand of a second monomer, allowing for the formation of the dimer. The surface of interactionbetween monomers also involves portion of chains D and E of the two monomers, ... this family.Finally, when crystallized in the presence of Cu(II), the protein shows the presence of the ion coordinated in a small cavity of the surface at the polar opposites of each monomer,...

Báo cáo khoa học: Structural and functional roles for b-strand 7 in the a-crystallin domain of p26, a polydisperse small heat shock protein from Artemia franciscana pdf

... within the a-crystallin domain, better understand the conse-quences of amino acid substitutions, and identify pro-tein regions involved in oligomer assembly. The fourmodiﬁed a-crystallin domain ... resem-blance, and the functional analysis mentioned previ-ously, indicate data obtained by examining bacteriallyproduced p26 are indicative of the protein synthesized in Artemia.Localization of amino acid ... remains uncer-tain.To summarize, analysis of individual amino acid substitutions, coupled with molecular modeling of protein structure, indicate that b-strand 7 of the a-crystallin domain is...

Báo cáo khoa học: Structural and functional analysis of the interaction of the AAA-peroxins Pex1p and Pex6p pptx

... hydrolysis of the nucleotide. To investi-gate the in uence of the binding and ⁄ or hydrolysis of ATP on the interaction of the AAA-peroxins, Pex1p and Pex6p carrying mutated ATP -binding sites ... do interact in vivo. We assigned their corresponding binding sites and elucidated the importance of ATP -binding and -hydrolysis of Pex1p and Pex6p for theirinteraction. We show that the interaction ... the binding sites of thesetwo AAA-proteins to their different protein regions and elucidated the importance of ATP -binding to the two AAA-cassettes of Pex1p and Pex6p for their inter-action.The...

Báo cáo khoa học: Structural and functional evidence for a singular repertoire of BMP receptor signal transducing proteins in the lophotrochozoan Crassostrea gigas suggests a shared ancestral BMP/activin pathway docx

... and the cysteine knot is boxed.Also boxed are the transmembrane domain, the ATP binding site, the L45 loop and the serine ⁄ threonine kinase domain. (B) The implied amino acid sequence of Cg-TGFbsfR2 ... the amino terminal end and C2deﬁnes the domain closest to the cell membrane. Acomparison of the inferred amino acid sequence of the C1 and C2 domains reveals that only the approximatespacing ... and XI of the receptor serine ⁄ threonine kinase domain [22]. Anotherstriking point is the phase conservation of the intron–exon boundaries that lie either side of the exon enco-ding the extracellular...

Báo cáo khoa học: Structural and functional characterization of human Iba proteins ppt

... Ca2+ binding and homodimerization of Iba1 and Iba2. Furthermore, F-actin binding and cross-linking assays were performed with both humanIba proteins, and their role in bacterial invasion wasinvestigated.ResultsCrystal ... conformationalchange of EF-hand proteins upon Ca2+ binding [18].Thus, it may be concluded that EF-hand 1 of the Ibaproteins is not capable of functional Ca2+ binding. Function of EF-hand 2 In both Iba1 ... phagocytosis[3] and to enhance the interaction of Iba1 with F-actinto a certain degree [11]. In this study F-actin binding and cross-linking by Iba proteins was calcium indepen-dent, conﬁrming previous...

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