Related Articles1H-NMR studies of bovine platelet factor 4: histidine assignments and interactions with heparin.
Biochim Biophys Acta. 1991 Jun 24;1078(2):208-18
Authors: Talpas CJ, Walz DA, Lee L
1H-NMR spectroscopy has been used to assign and to characterize the two histidine C2H resonances of the heparin binding protein, bovine platelet factor 4. One histidine has a pKa value of 6.51 at 27 degrees C; the second histidine exhibits 2 pKa values of 5.52 and 5.66 at 27 degrees C. The two histidine resonances have been assigned by an analysis of their deuterium exchange kinetics. Both resonances are solvent accessible with half-times of exchange at pH 8.8 of 3.3 and 4.0 days. These two resonances have been assigned by digesting partially deuterated protein with Staphylococcus aureus V-8 proteinase, separating and purifying the resulting peptides, and determining their relative and residual hydrogen content by NMR. The results indicate that His-38 has the lower pKa value and the slower deuterium exchange rate, whereas His-50 has the higher pKa value and the faster deuterium exchange rate at pH 8.8. The 1H-NMR resonance of His-38 of bovine platelet factor 4 is preferentially perturbed by the introduction of heparin. This observation and the presence of His-38 within the belt of positively charged residues around the platelet factor 4 tetramer supports the model of the platelet factor 4-heparin complex in which the polysaccharide crosses over each of the 2 alpha-helices of the 2 dimers at right angles.
Exploring platelet chemokine antimicrobial activity: NMR backbone dynamics studies of NAP-2 and TC-1.
Exploring platelet chemokine antimicrobial activity: NMR backbone dynamics studies of NAP-2 and TC-1.
Exploring platelet chemokine antimicrobial activity: NMR backbone dynamics studies of NAP-2 and TC-1.
Antimicrob Agents Chemother. 2011 Feb 14;
Authors: Nguyen LT, Kwakman PH, Chan DI, Liu Z, de Boer L, Zaat SA, Vogel HJ
The platelet chemokines NAP-2 and TC-1 differ by only two amino acids at their carboxy-terminal end. Nevertheless they display a significant difference in their direct antimicrobial activity, with the longer NAP-2 being inactive...
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[NMR paper] Heparin binding to platelet factor-4. An NMR and site-directed mutagenesis study: arg
Heparin binding to platelet factor-4. An NMR and site-directed mutagenesis study: arginine residues are crucial for binding.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles Heparin binding to platelet factor-4. An NMR and site-directed mutagenesis study: arginine residues are crucial for binding.
Biochem J. 1995 Dec 1;312 ( Pt 2):357-65
Authors: Mayo KH, Ilyina E, Roongta V, Dundas M, Joseph J, Lai CK, Maione T, Daly TJ
Native platelet factor-4 (PF4) is an...
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[NMR paper] NMR solution structure of the 32-kDa platelet factor 4 ELR-motif N-terminal chimera:
NMR solution structure of the 32-kDa platelet factor 4 ELR-motif N-terminal chimera: a symmetric tetramer.
NMR solution structure of the 32-kDa platelet factor 4 ELR-motif N-terminal chimera: a symmetric tetramer.
Biochemistry. 1995 Sep 12;34(36):11399-409
Authors: Mayo KH, Roongta V, Ilyina E, Milius R, Barker S, Quinlan C, La Rosa G, Daly TJ
Native human platelet factor 4 (PF4) is a homotetrameric protein (70 residues/subunit) known for its anticoagulant heparin binding activity. 2D 15N--1H HSQC NMR experiments of native PF4 in solution...
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[NMR paper] Comparative studies of the interaction of human and bovine platelet factor 4 with hep
Comparative studies of the interaction of human and bovine platelet factor 4 with heparin using histidine NMR resonances as spectroscopic probes.
Related Articles Comparative studies of the interaction of human and bovine platelet factor 4 with heparin using histidine NMR resonances as spectroscopic probes.
J Protein Chem. 1993 Jun;12(3):303-9
Authors: Talpas CJ, Lee L
The pKa values of His-38 and His-50 of the heparin-binding protein, bovine platelet factor 4, are 5.6 and 6.5, respectively, as determined by 1H NMR spectroscopy. The 1H NMR...
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[NMR paper] Sequential 1H NMR assignments of kistrin, a potent platelet aggregation inhibitor and
Sequential 1H NMR assignments of kistrin, a potent platelet aggregation inhibitor and glycoprotein IIb-IIIa antagonist.
Related Articles Sequential 1H NMR assignments of kistrin, a potent platelet aggregation inhibitor and glycoprotein IIb-IIIa antagonist.
Biochemistry. 1992 Feb 4;31(4):1031-9
Authors: Adler M, Wagner G
Sequence-specific nuclear magnetic resonances assignments have been obtained for the protons of kistrin. Kistrin is a small naturally occurring snake venom protein that inhibits platelet aggregation by blocking the interaction...
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[NMR paper] Sequence-specific 1H NMR assignments and structural characterization of bovine semina
Sequence-specific 1H NMR assignments and structural characterization of bovine seminal fluid protein PDC-109 domain b.
Related Articles Sequence-specific 1H NMR assignments and structural characterization of bovine seminal fluid protein PDC-109 domain b.
Biochemistry. 1991 Feb 12;30(6):1663-72
Authors: Constantine KL, Ramesh V, Bányai L, Trexler M, Patthy L, Llinás M
Sequence-specific resonance assignments for the isolated second or b domain of the bovine seminal fluid protein PDC-109 have been obtained from analysis of two-dimensional 1H...
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[NMR paper] Low-affinity platelet factor 4 1H NMR derived aggregate equilibria indicate a physiol
Low-affinity platelet factor 4 1H NMR derived aggregate equilibria indicate a physiologic preference for monomers over dimers and tetramers.
Related Articles Low-affinity platelet factor 4 1H NMR derived aggregate equilibria indicate a physiologic preference for monomers over dimers and tetramers.
Biochemistry. 1991 Jan 29;30(4):925-34
Authors: Mayo KH
Low-affinity platelet factor 4 (LA-PF4), unlike another related, sequentially homologous (about 50%) platelet-specific protein, platelet factor 4 (PF4), is an active mitogenic and chemotactic...