Chapter 5, Problem 29CQ

(a)

Summary Introduction

To explain: The reason for the different positive charges on different particles of the protein.

Concept introduction: The proteins involves creating positively charged ions of the protein and separating them, according to their mass to charge ratio (m/z) is called Electrospray ionization mass spectrometry (ESI-MS). It is the ionization technique to produce ions using an electrospray from macromolecules.

(b)

Summary Introduction

To determine: The maximum positive charge present in hen egg-white lysozyme (HEWL).

Concept introduction: The proteins involves creating positively charged ions of the protein and separating them, according to their mass to charge ratio (m/z) is called Electrospray ionization mass spectrometry (ESI-MS). It is the ionization technique to produce ions using an electrospray from macromolecules.

Given: The amino acid composition (in numbers of residues per chain) of hen egg-white lysozyme (HEWL) is as follows:

P 2   Y 3   N 14   H 1

D 7   M 2   L 8   E 2

C 8   R 11   G 12   F 3

A 12   I 6   K 6   V 6

S 10   W 6   T 7   Q 3