Peptides distribution

As the layer technique with CHCA produces a homogeneous peptide distribution within the matrix, record the spectra from all parts of the sample spot. For samples prepared with DHB, use only the outer edge of the matrix spot, as the center part produces mostly salt clusters and sodiated peptide ions. 

When the medium reaches a temperature of about 55°C, divide it into aliquots and add in each of them increasing concentrations of the PRP (from 1 to 10 pM in the case of Bac7-derived fragments). Stir or shake thoroughly to get a homogenous peptide distribution. 

Stoeckli M, Staab D, Schweitzer A, Gardiner J, Seebach D (2007) Imaging of a p-peptide distribution in whole-body mice sections by MALDI mass spectrometry. J Am Soc Mass Spectrom 18 1921-1924. doi 10.1016/j.jasms.2007.08.005... 

Altelaar, A.F.M. et al., High-resolution MALDI imaging mass spectrometry allows localization of peptide distributions at cellular length scales in pituitary tissue sections, Int. J. Mass Spectrom., 260(2-3), 203, 2007. 

In a preliminary study, we compared the reproducibility and peptide distribution across eight salt fractions (0 to 2M ammonium acetate, pH = 3.5) for a protein extract of control U937 cells. Figure 8.3a compares the distribution of peptide clusters for individual salt fractions to that observed for the injection of the same sample on a one-dimensional nanoLC-chip-MS system. A total of 2028 unique peptide clusters were obtained for the injection of 100 ng of protein digest for the Cig-only separation whereas 13 848 peptide clusters (a 6-fold increase) were detected for 1.5 pg injection on the combined SCX/Cig separation. In addition to the increased sample loading capacity of SCX, its... 

Distribution and processing of egg-laying peptides, neuropeptide Y, cardio active peptides, new peptides in F-cluster including Aplysia insulin, post-trans-lational modifications of R3-14 peptides in cells, peptide distribution and transport in connectives. Aplasia mytilus inhibitory-peptide-related peptides. 

Once the filtered list is determined and tested against unlabeled data sets collected under HX-MS conditions, it can be applied for deuteration analysis of the full set of deuterated samples. The detection and quantification of deuterium levels rely upon the validity of this list. It proceeds to determine deuterium levels by budding theoretical isotopic expansions of a native peptide distribution across aU deuteration levels and calculating the best fit between the actual isotopic distribution and the... 

Rankenberg et al studied the membrane-spanning GWALP23 peptide distribution in DOPC, DMPC and DLPC bilayers of different thicknesses. Gleason et al exchanged the tryptophan residue for tyrosine in GW ALP peptides to study the membrane anchor properties of these residues. 

Stoeckli, M., Staab, D., Schweitzer, A., Gardiner, J., Seebach, D. (2007) Imaging of a [beta]-peptide distribution in whole-body... 

Using Fleximaging, digestion peptide distribution within the tissue is generated to check that all fragments of the same protein really provide the same localization. 

The 30 xm rastering of the tissue (so-called oversampling technique with a < 100 xm diameter laser spot size), nicely allows for clear differential localization of peptide families, including ones exclusively localized in the ca, and others which are predominant in the cc. Within the cc, even a distinction can be made between peptide distributions over the glandular and the storage lobes. The only way this type of peptide localization data could be obtained in the past was by tedious individual dissection of the minute subparts of the little glands followed by peptide... 

Altelaar, A. F. M. Taban, I. M. McDonneU, L. A. Verhaert, P de Lange, R. P. J. Adan, R. A. H. Mooi, W. J. Heeren, R. M. A. Piersma, S. R., High-resolution MALDl imaging mass spectrometry allows locahzation of peptide distributions at cellular length scales in pituitary tissue sections , Int. J. Mass Spectrom. 2007, 260, 203-211. 

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