Jan Jensen edited In_the_case_of_2OED__.tex  almost 9 years ago

Commit id: 06f273aa30fdfde717843a4e1adb89cff26ea670

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In the case of 2OED the RMSD ($r$) value for CB can be reduced (increased) to 1.8 ppm (0.71) by removing a single outlier identified by the Generalized Extreme Studentized Deviate Test. The outlier is Ala20 for which ProCS15 and DFT predict a CB chemical shielding value of XX and xx ppm, respectively. Inspection of the structure shows that the CB atom is only xx 3.1  Å from the center of the phenol ring N atom  of Tyr45, so this deviation is most likely due to ring current effects, which are Ala26 - an interaction  not yet included for non-hydrogen atoms taken into account  in ProCS. the parameterization of ProCS15.  Similarly (also for 2OED), the RMSD ($r$) value for H can be reduced (increased) to 0.6 ppm (0.91) by removing a single outlier identified by the Generalized Extreme Studentized Deviate Test. The outlier is Gln2 for which ProCS15 and DFT predict a CB chemical shielding value of XX and xx ppm, respectively. Inspection of the structure shows that the H atom is within 1.77 Å of the OE1 atom of the Gln side chain and with 2.54 Å of an HE atom of the Met1 side chain. While the former interaction should be included in the $\sigma_{BB}^{i-1}$ term, the latter interaction is not and may be responsible for the large deviation. This residue is also identified as an outlier for N and removing it reduces (increases) the RMSD ($r$) value to XX and XX, respectively.