A protein consists of two types of peptide chains (A and B) with an unknown stoichiometry (AxBy). When you ran this protein directly on reversed phase-HPLC with UV monitor set at 280 nm, two peaks were resolved. Mass spec determined that the peaks represented Chain A and Chain B, respectively. The peak area is 500,000 for Peak A (Chain A) and 100,000 for Peak B (Chain B). The molecular masses of Chain A and Chain B are 25,000 and 5000, respectively. The extinction coefficients for Chain A and Chain B are 1 mL/mg.cm and 0.5 mL/mg.cm, respectively. Please calculate x/y.

A protein consists of two types of peptide chains (A and B) with an unknown stoichiometry (AxBy). When you ran this protein directly on reversed phase-HPLC with UV monitor set at 280 nm, two peaks were resolved. Mass spec determined that the peaks represented Chain A and Chain B, respectively. The peak area is 500,000 for Peak A (Chain A) and 100,000 for Peak B (Chain B). The molecular masses of Chain A and Chain B are 25,000 and 5000, respectively. The extinction coefficients for Chain A and Chain B are 1 mL/mg.cm and 0.5 mL/mg.cm, respectively. Please calculate x/y.

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter14: Mass Spectrometry

Section: Chapter Questions

Problem 14.37P

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