A simple and sensitive experiment for measurement of JCC couplings between backbone carbonyl and methyl carbons in isotopically enriched proteins

1993 ◽  
Vol 3 (4) ◽  
Author(s):  
Stephan Grzesiek ◽  
GeertenW. Vuister ◽  
Ad Bax
Keyword(s):  
Backbone Carbonyl ◽  
Sensitive Experiment

Using Cluster Analysis to Improve Marketing Experiments

1971 ◽  
Vol 8 (3) ◽  
pp. 340-347 ◽  
Author(s):  
George S. Day ◽  
Roger M. Heeler
Keyword(s):  
Cluster Analysis ◽  
Space Representation ◽  
Reduced Space ◽  
High Degree ◽  
Degree Of Similarity ◽  
Sensitive Experiment ◽  
Selection Of

When the selection of a sample of stores or cities requires a high degree of similarity among the test units in order to ensure a sensitive experiment, the sample may no longer represent the market. These conflicting requirements can be satisfied by choosing the sample from clusters displayed in a reduced space representation of the market.

Inter-residue interactions in alpha-helical transmembrane proteins

2018 ◽  
Vol 35 (15) ◽  
pp. 2578-2584 ◽  
Author(s):  
Eduardo Mayol ◽  
Mercedes Campillo ◽  
Arnau Cordomí ◽  
Mireia Olivella
Keyword(s):  
Membrane Proteins ◽  
Present Report ◽  
Protein Structures ◽  
Transmembrane Proteins ◽  
Globular Proteins ◽  
Supplementary Information ◽  
Backbone Carbonyl ◽  
Composition Characteristic ◽  
Almost All ◽  
Residue Composition

Abstract Motivation The number of available membrane protein structures has markedly increased in the last years and, in parallel, the reliability of the methods to detect transmembrane (TM) segments. In the present report, we characterized inter-residue interactions in α-helical membrane proteins using a dataset of 3462 TM helices from 430 proteins. This is by far the largest analysis published to date. Results Our analysis of residue–residue interactions in TM segments of membrane proteins shows that almost all interactions involve aliphatic residues and Phe. There is lack of polar–polar, polar–charged and charged–charged interactions except for those between Thr or Ser sidechains and the backbone carbonyl of aliphatic and Phe residues. The results are discussed in the context of the preferences of amino acids to be in the protein core or exposed to the lipid bilayer and to occupy specific positions along the TM segment. Comparison to datasets of β-barrel membrane proteins and of α-helical globular proteins unveils the specific patterns of interactions and residue composition characteristic of α-helical membrane proteins that are the clue to understanding their structure. Availability and implementation Results data and datasets used are available at http://lmc.uab.cat/TMalphaDB/interactions.php. Supplementary information Supplementary data are available at Bioinformatics online.

scholarly journals On the satisfaction of backbone-carbonyl lone pairs of electrons in protein structures

2016 ◽  
Vol 25 (4) ◽  
pp. 887-897 ◽  
Author(s):  
Gail J. Bartlett ◽  
Derek N. Woolfson
Keyword(s):  
Protein Structures ◽  
Backbone Carbonyl ◽  
Lone Pairs

scholarly journals Molecular determinants for agonist recognition and discrimination in P2X2 receptors

2019 ◽  
Vol 151 (7) ◽  
pp. 898-911 ◽  
Author(s):  
Federica Gasparri ◽  
Jesper Wengel ◽  
Thomas Grutter ◽  
Stephan A. Pless
Keyword(s):  
Drug Targets ◽  
P2x Receptors ◽  
Carbonyl Oxygen ◽  
Site Directed Mutagenesis ◽  
Side Chain ◽  
Ligand Recognition ◽  
Directed Mutagenesis ◽  
Backbone Carbonyl ◽  
Molecular Determinants ◽  
Atp Analogues

P2X receptors (P2XRs) are trimeric ligand-gated ion channels that open a cation-selective pore in response to ATP binding. P2XRs contribute to synaptic transmission and are involved in pain and inflammation, thus representing valuable drug targets. Recent crystal structures have confirmed the findings of previous studies with regards to the amino acid chains involved in ligand recognition, but they have also suggested that backbone carbonyl atoms contribute to ATP recognition and discrimination. Here we use a combination of site-directed mutagenesis, amide-to-ester substitutions, and a range of ATP analogues with subtle alterations to either base or sugar component to investigate the contributions of backbone carbonyl atoms toward ligand recognition and discrimination in rat P2X2Rs. Our findings demonstrate that while the Lys69 backbone carbonyl makes an important contribution to ligand recognition, the discrimination between different ligands is mediated by both the side chain and the backbone carbonyl oxygen of Thr184. Together, our data demonstrate how conserved elements in P2X2Rs recognize and discriminate agonists.

Long-term future projections for the Greenland and Antarctic ice sheets with the model SICOPOLIS

2021 ◽  
Author(s):  
Ralf Greve ◽  
Christopher Chambers ◽  
Reinhard Calov ◽  
Takashi Obase ◽  
Fuyuki Saito ◽  
...  
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Ice Sheets ◽  
Future Climate ◽  
Model Intercomparison ◽  
Mass Losses ◽  
Intercomparison Project ◽  
Sensitive Experiment ◽  
Antarctic Ice Sheets

<p>The Coupled Model Intercomparison Project Phase 6 (CMIP6) is a major international climate modelling initiative. As part of it, the Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) was devised to assess the likely sea-level-rise contribution from the Greenland and Antarctic ice sheets until the year 2100. This was achieved by defining a set of future climate scenarios by evaluating results of CMIP5 and CMIP6 global climate models (GCMs, including MIROC) over and surrounding the Greenland and Antarctic ice sheets. These scenarios were used as forcings for a variety of ice-sheet models operated by different working groups worldwide (Goelzer et al. 2020, doi: 10.5194/tc-14-3071-2020; Seroussi et al. 2020, doi: 10.5194/tc-14-3033-2020).</p><p>Here, we use the model SICOPOLIS to carry out extended versions of the ISMIP6 future climate experiments for the Greenland and Antarctic ice sheets until the year 3000. For the atmospheric forcing (anomalies of surface mass balance and temperature) beyond 2100, we sample randomly the ten-year interval 2091-2100, while the oceanic forcing beyond 2100 is kept fixed at 2100 conditions. We conduct experiments for the pessimistic, "business as usual" pathway RCP8.5 (CMIP5) / SSP5-8.5 (CMIP6), and for the optimistic RCP2.6 (CMIP5) / SSP1-2.6 (CMIP6) pathway that represents substantial emissions reductions. For the unforced, constant-climate control runs, both ice sheets are stable until the year 3000. For RCP8.5/SSP5-8.5, they suffer massive mass losses: For Greenland, ~1.7 m SLE (sea-level equivalent) for the 12-experiment mean, and ~3.5 m SLE for the most sensitive experiment. For Antarctica, ~3.3 m SLE for the 14-experiment mean, and ~5.3 m SLE for the most sensitive experiment. For RCP2.6/SSP1-2.6, the mass losses are limited to a two-experiment mean of ~0.26 m SLE for Greenland, and a three-experiment mean of ~0.25 m SLE for Antarctica. Climate-change mitigation during the next decades will therefore be an efficient means for limiting the contribution of the ice sheets to sea-level rise in the long term.</p>

The Comparison Study of Targeting Observation for Extratropical Transition of Hurricane Fabian

2012 ◽  
Vol 518-523 ◽  
pp. 5840-5845
Author(s):  
Hua Chen ◽  
Xue Ting Zhang
Keyword(s):  
Positive Impact ◽  
Signal Propagation ◽  
Comparison Study ◽  
Extratropical Transition ◽  
Random Experiment ◽  
Targeted Observations ◽  
Propagation Methods ◽  
And Control ◽  
The Impact ◽  
Sensitive Experiment

This study compares the propagation methods of the impact of targeted observations during the extratropical transition (ET) of Hurricane Fabian in three denial experiments. In sensitive experiment, the signal (forecast difference between denial experiments and control) propagates from the tropical cyclone (TC) to the midlatitude jet through the interaction between the TC and the jet itself. Thereafter, signals propagate eastward along the jet by way of Rossby wave packets. Some differences exist between random/Atlantic and sensitive experiment although many of their signal propagation characteristics are similar. The signal in random experiment is the weakest, and that in Atlantic experiment is the strongest. In Atlantic experiment, initial signals appear not only in Fabian, but also in other regions. In some cases, signals even do not appear in Fabian. Its propagation method is similar to that in sensitive and random experiment except some signals exist at ridges occasionally. From the discussion above, we conclude that targeted observations have more positive impact than random observations, but can not replace observations taken in the whole Atlantic.

Ca2+Coordination to Backbone Carbonyl Oxygen Atoms in Calmodulin and Other EF-Hand Proteins: 15N Chemical Shifts as Probes for Monitoring Individual-Site Ca2+Coordination†

Biochemistry ◽  
1998 ◽  
Vol 37 (20) ◽  
pp. 7617-7629 ◽  
Author(s):  
Rodolfo R. Biekofsky ◽  
Stephen R. Martin ◽  
J. Peter Browne ◽  
Peter M. Bayley ◽  
James Feeney
Keyword(s):  
Chemical Shifts ◽  
Carbonyl Oxygen ◽  
Backbone Carbonyl ◽  
Individual Site ◽  
Ef Hand ◽  
Oxygen Atoms
Sign in / Sign up

Export Citation Format

Share Document