1. |
|
|
2. |
|
|
3. |
|
|
4. |
|
|
5. |
- Berndt, Kurt D, et al.
(författare)
-
Determination of a high-quality nuclear magnetic resonance solution structure of the bovine pancreatic trypsin inhibitor and comparison with three crystal structures
- 1992
-
Ingår i: Journal of Molecular Biology. - : Elsevier BV. - 0022-2836. ; 227, s. 757-775
-
Tidskriftsartikel (refereegranskat)abstract
- A high-quality three-dimensional structure of the bovine pancreatic trypsin inhibitor (BPTI) in aqueous solution was determined by 1H nuclear magnetic resonance (n.m.r.) spectroscopy and compared to the three available high-resolution X-ray crystal structures. A newly collected input of 642 distance constraints derived from nuclear Overhauser effects and 115 dihedral angle constraints was used for the structure calculations with the program DIANA, followed by restrained energy minimization with the program AMBER. The BPTI solution structure is represented by a group of 20 conformers with an average root-mean-square deviation (RMSD) relative to the mean solution structure of 0.43 A for backbone atoms and 0.92 A for all heavy atoms of residues 2 to 56. The pairwise RMSD values of the three crystal structures relative to the mean solution structure are 0.76 to 0.85 A for the backbone atoms and 1.24 to 1.33 A for all heavy atoms of residues 2 to 56. Small local differences in backbone atom positions between the solution structure and the X-ray structures near residues 9, 25 to 27, 46 to 48 and 52 to 58, and conformational differences for individual amino acid side-chains were analyzed for possible correlations with intermolecular protein-protein contacts in the crystal lattices, using the pairwise RMSD values among the three crystal structures as a reference.
|
|
6. |
|
|
7. |
- Brunne, R M, et al.
(författare)
-
Structure and internal dynamics of the bovine pancreatic trypsin inhibitor in aqueous solution from long-time molecular dynamics simulations
- 1995
-
Ingår i: Proteins. - : Wiley. - 0887-3585 .- 1097-0134. ; 23:1, s. 49-62
-
Tidskriftsartikel (refereegranskat)abstract
- Structural and dynamic properties of bovine pancreatic trypsin inhibitor (BPTI) in aqueous solution are investigated using two molecular dynamics (MD) simulations: one of 1.4 ns length and one of 0.8 ns length in which atom-atom distance bounds derived from NMR spectroscopy are included in the potential energy function to make the trajectory satisfy these experimental data more closely. The simulated properties of BPTI are compared with crystal and solution structures of BPTI, and found to be in agreement with the available experimental data. The best agreement with experiment was obtained when atom-atom distance restraints were applied in a time-averaged manner in the simulation. The polypeptide segments found to be most flexible in the MD simulations coincide closely with those showing differences between the crystal and solution structures of BPTI.
|
|
8. |
- Elgán, Tobias H., et al.
(författare)
-
Determinants of activity in glutaredoxins : An in vitro evolved Grx1-like variant of Escherichia coli Grx3
- 2010
-
Ingår i: Biochemical Journal. - 0264-6021 .- 1470-8728. ; 430:3, s. 487-495
-
Tidskriftsartikel (refereegranskat)abstract
- The Escherichia coli glutaredoxins 1 and 3 (Grx1 and Grx3) are structurally similar (37% sequence identity), yet have different activities in vivo. Unlike Grx3, Grx1 efficiently reduces protein disulfides in proteins such as RR (ribonucleotide reductase), whereas it is poor at reducing S-glutathionylated proteins. An E. coli strain lacking genes encoding thioredoxins 1 and 2 and Grx1 is not viable on either rich or minimal medium; however, a M43V mutation in Grx3 restores growth under these conditions and results in a Grx1-like protein [Ortenberg, Gon, Porat and Beckwith (2004) Proc. Natl. Acad. Sci. U.S.A. 101, 7439-7944]. To uncover the structural basis of this change in activity, we have compared wild-type and mutant Grx3 using CD and NMR spectroscopy. Ligand-induced stability measurements demonstrate that the Grx3(M43V/C65Y) mutant has acquired affinity for RR. Far-UV CD spectra reveal no significant differences, but differences are observed in the near-UV region indicative of tertiary structural changes. NMR 1H- 15N HSQC (heteronuclear single quantum coherence) spectra show that approximately half of the 82 residues experience significant (Δδ > 0.03 p.p.m.) chemical shift deviations in the mutant, including nine residues experiencing extensive (Δδ ≥ 0.15 p.p.m.) deviations. To test whether the M43V mutation alters dynamic properties of Grx3, H/D (hydrogen/deuterium) exchange experiments were performed demonstrating that the rate at which backbone amides exchange protons with the solvent is dramatically enhanced in the mutant, particularly in the core of the protein. These data suggest that the Grx1-like activity of the Grx3(M43V/C65Y) mutant may be explained by enhanced intrinsic motion allowing for increased specificity towards larger substrates such as RR.
|
|
9. |
- Güntert, P, et al.
(författare)
-
The Program Asno for Computer-Supported Collection of Noe Upper Distance Constraints as Input for Protein-Structure Determination
- 1993
-
Ingår i: Journal of Biomolecular NMR. - 0925-2738 .- 1573-5001. ; 3:5, s. 601-606
-
Tidskriftsartikel (refereegranskat)abstract
- A new program, ASNO ('ASsign NOes'), for computer-supported NOE cross-peak assignments is described. ASNO is used for structure refinement in several rounds of NOESY cross-peak assignments and 3D structure calculations, where the preliminary structures are used as a reference to resolve ambiguities in NOE assignments which are otherwise based on the chemical shifts available from the sequence-specific resonance assignments. The practical use of ASNO for proteins is illustrated with the structure determination of Dendrotoxin K from Dendroaspis polylepis polylepis.
|
|
10. |
- Kälsch, Hagen, et al.
(författare)
-
Are air pollution and traffic noise independently associated with atherosclerosis : the Heinz Nixdorf Recall Study
- 2014
-
Ingår i: European Heart Journal. - : Oxford University Press (OUP). - 0195-668X .- 1522-9645. ; 35:13, s. 853-60
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS: Living close to high traffic has been linked to subclinical atherosclerosis, however it is not clear, whether fine particulate matter (PM) air pollution or noise, two important traffic-related exposures, are responsible for the association. We investigate the independent associations of long-term exposure to fine PM and road traffic noise with thoracic aortic calcification (TAC), a reliable measure of subclinical atherosclerosis.METHODS AND RESULTS: We used baseline data (2000-2003) from the German Heinz Nixdorf Recall Study, a population-based cohort of 4814 randomly selected participants. We assessed residential long-term exposure to PM with a chemistry transport model, and to road traffic noise using façade levels from noise models as weighted 24 h mean noise (Lden) and night-time noise (Lnight). Thoracic aortic calcification was quantified from non-contrast enhanced electron beam computed tomography. We used multiple linear regression to estimate associations of environmental exposures with ln(TAC+1), adjusting for each other, individual, and neighbourhood characteristics. In 4238 participants (mean age 60 years, 49.9% male), PM2.5 (aerodynamic diameter ≤2.5 µm) and Lnight are both associated with an increasing TAC-burden of 18.1% (95% CI: 6.6; 30.9%) per 2.4 µg/m(3) PM2.5 and 3.9% (95% CI 0.0; 8.0%) per 5dB(A) Lnight, respectively, in the full model and after mutual adjustment. We did not observe effect measure modification of the PM2.5 association by Lnight or vice versa.CONCLUSION: Long-term exposure to fine PM and night-time traffic noise are both independently associated with subclinical atherosclerosis and may both contribute to the association of traffic proximity with atherosclerosis.
|
|