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Chapter 22: QGE (page 599)

Protein molecular mass from electrospray. The enzyme lysozyme 59exhibits MHnn+peaks at m/z = 1789.1, 1590.4, 1301.5 and 1 193.1. Follow the procedure of Table 22-3 to find the mean molecular mass and its standard deviation.

Short Answer

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The mean molecular mass and standard deviation were calculated.

Step by step solution

01

Definition of Mean molecular mass and standard deviation

  • The average molar mass of a chemical mixture is defined as the mean molecular mass of the mixture.
  • Standard deviation (SD) is a metric that can be used to quantify the overall amount of variation or dispersion in a group of numbers or values.
02

Determine the mean molecular mass and its standard deviation

For each protein, the mean molecular mass and standard deviation must be determined.

The peaks shown belong to the lysozyme isotope 59.

We can readily determine the mean molecular mass and its standard deviation using the electrospray mass spectrum of lysozyme, as shown in Figure 1.


For each protein, the mean molecular mass and standard deviation were calculated.

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