Lysozyme mass spectrum

Figure 12.9 MALDI-TOF mass spectrum of chicken egg-white lysozyme. The peak at 14,307.7578 daltons (amu) is due to the monoprotonated protein, M+H+, and that at 28,614.2188 daltons is due to an impurity formed by dimerization of the protein. Other peaks are various protonated species, M+H rH ...

Figure 8. Ion chromatogram (top) of a lysozyme derived tryptic peptide fraction obtained using thermospray discharge ionization HPLC-MS. The resulting mass spectrum of one of the peptides (val-phe-gly-arg) is shown (bottom).

The Mass Spectrum of the Peak Eluted at 30.35 Minutes in the Tryptic Digest Chromatogram of Lysozyme w/R A Courtesy of the Hewlett-Packard Company. 

FIGURE 5.7 ECD FT-ICR mass spectrum of [M + 2H] +ions of the lysozyme [52-63] tryptic peptide FESNFNTQATNR. 

FIGURE 6.15 Laser desorption mass spectrum of lysozyme using a slurry of glycerol and ultrafine metal powder as the matrix. (Reprinted with permission from reference 53). 

Figure 7.1. Laser ionization mass spectrum of lysozyme from chicken egg white, mol. wt. 14,306 Da. (Reproduced with permission from Tanaka, K. Waki, H. Ido, Y. Akita, S. Yoshida, Y Yoshida, T. Protein and polymer analyses up to miz 100,000 by laser ionization time-of-flight mass spectrometry. Rapid Commun. Mass Spectrom. 1988, 2, 151-153.)...

ESI spectrum of phage X lysozyme m/z in Th and the number of charges are indicated on each peak. The molecular mass is measured as being 17 828 2.0 Da. 

The TOF technique is considerably more sensitive than the magnetic-sector alternative, and protein samples of up to 100 kilodaltons (100,000 amu) can be separated with a mass accuracy of 3 ppm. Figure 10.9 shows a MALDI-TOF spectrum of chicken egg-white lysozyme, MW = 14,306.7578 daltons. (Biochemists generally use the unit dalton, abbreviated Da, instead of amu.)... 

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