Deuterium levels

The PLIMSTEX curve for 0.3 pM WT-IFABP titrated with potassium oleate fits well with a 1 1 binding model [22, 24], The K and ADi (difference between the average deuterium level of one-ligand-bound protein and that of apo protein) for WT-IFABP are (2.6 + 0.6) x lO and 13.8 + 0.7 (Table 11.1), respectively, indicating that a strong interaction between oleate and WT-IFABP occurs with protection of 14 backbone amide hydrogens. 

These optimal predictions were recently extended in Ref. [1] to many more levels, as all hydrogen and deuterium levels with principal quantum number n < 200 had their energy calculated, along with that of transitions between any pair of levels. The precision on the transitions duly includes correlations between level energies (see, e.g., Eq. (18) in [1]), so that their evaluation is optimally precise. 

A large number of growth factors, individually and in combination, were included in the nutrient solution and their effect on the growth of duckweed at high levels of deuteration was observed. At deuterium levels in... 

Once the filtered list is determined and tested against unlabeled data sets collected under HX-MS conditions, it can be applied for deuteration analysis of the full set of deuterated samples. The detection and quantification of deuterium levels rely upon the validity of this list. It proceeds to determine deuterium levels by budding theoretical isotopic expansions of a native peptide distribution across aU deuteration levels and calculating the best fit between the actual isotopic distribution and the... 

Figure 7,2 Extraction of rate constants by fitting the data to the three-component model. Two representative peptides (HC V254-267 and HC E233-M244) of native (control) and reduced gC2 are taken as examples. Deuterium levels were corrected for back-exchange. Nonlinear curve fitting were performed on KaleidaCraph (Synergy Software). Optimized parameters are shown In the Inserted tables...

Pascal, B.D., Chalmers, M.J., Busby, S.A., etal. (2007) The Deuterator Software for the determination of backbone amide deuterium levels from H/D exchange MS data BMC Bioinform, 8 (1), 156. 

Figure 8.9 The targeted HX-ETD strategy to determine site-specific deuterium levels. Following HX, quench, and enzymatic cleavage, only peptides exhibiting differential deuterium uptake in states A and B (regions marked with yellow and pink) are selected for ETD fragmentation. The time points with the maximal difference in the deuterium uptake are selected for fragmentation (See insert for color representation of the figure.)...

Gross and coworkers used the bottom-up HX-FTD method to pinpoint changes in deuterium uptake for single amides in wild-t5q)e and mutant form of apolipoprotein F4 (Apo F4) [65]. Apo F4, a major risk factor for Alzheimer s and cardiovascular diseases, is prone to aggregation where the oligomerization is promoted by residues in the C-terminal region. By comparison of deuterium levels in individual amide residues in wild-type Apo F4 and a mutant that remains in its monomeric form due to the substitutions of four C-terminal residues, several residues involved in the selfassociation process of Apo F4 were identified. 

The two naturally occurring isotopes of hydrogen are the proton and the deuteron with natural abundances of 99.985 % and 0.015 %. re.spec-tively. Whilst the former with I- 1/2 is the most commonly studied of all magnetic nuclei, the latter with /= is rarely studied in natural abundance and then only for a few specialist applications. One such application, the determination of deuterium levels in samples, is discussed in Section... 

The addition and removal of boron is easily performed although it is not yet fully automated or automatically monitored. The deuterium levels have been higher than predicted but the concentration has been kept below the maximum permissible level of 7 - An Increase of the recombination capacity by about 50 is proposed. 

In the prototype, the somewhat enhanced radlolysls rate observed causes no embarrassment. The Installed recombination unit handles the load satisfactorily. The deuterium level in the helium blanket is approximately which is well below the minimum concentration of 8-10 necessary to support combustion. Our design concentration of could be achieved by adopting a higher gas recirculation rate (about 50 cfm) and we shall do this as soon as an opportunity arises to Install greater recirculation pump capacity. 

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