Peptide molecular weights

Apply to the column 1.0ml of peptide solution (dissolved in equilibration buffer) to be reduced. Normally, small peptides (molecular weight less than or equal to that of insulin) require no deforming agent (denaturant) such as guanidine to be completely reduced. 

Covey, T.R. Bonner, R.F. Shushan, B.I. Henion, J.D. The Determination of Protein, Oligonucleotide, and Peptide Molecular Weights by lon-Spray-MS. Rapid Commun. Mass Spectrom. 1988, 2, 249-256. 

Selective detection of posttranslational modifications is possible through collision-induced formation of low-mass fragment ions that serve as selective markers for the modifications of interest. Collision-induced fragmentation, which is turned on while scanning the lower mass range, is turned off during the remainder of the scan (e.g. m/z 400-2400). In this way peptide molecular weight information and modification-selective, low-mass marker ions are detected in the... 

T.R. Covey, R.F. Bonner, B.I. Shushan, J.D. Henion, The determination of protein, oligonucleotide and peptide molecular weights by ESI-MS, Rapid Commun. Mass Spectrom., 2 (1988) 249. 

Optimum flow rate as a function of peptide molecular weight. 

Disulfide bonding is determined by comparing peptide molecular weights with and without reduction and alkylation. 

The amino acids with uncharged polar R groups are G, S, T, C, Y, N, and Q. Let a large population of 100-unit peptides be prepared using these components chosen at random, (a) Construct a plot of the probability density function based on the peptide molecular weight, (b) Do likewise for the probability distribution function. Do the plots match expectations formed prior to the exercise ... 

Fig. 7. GPC traces illustrating the evolution of pols peptide molecular weight and monomer consumption during the pol3rmerization of y-benzyl-L-glutamate N-carboxyanhydride (Bn-Glu NCA). Targeted number-average degree of polymerization was 440. After 17 h, monomer consumption is >99%.

Proteolysis has been widely used to improve the surface properties of proteins [3,4]. Partial proteolysis may facilitate the unfolding of polypeptides and increase the heterogeneity of the protein, that is, the peptide molecular weight distribution, resulting in improved surface properties. The factors affecting enzymatic hydrolysis as well as the production of protein hydrolysates are described in detail in Chapter 2 of this book. In this section, therefore, we show only examples of the systematic approach on a structural factor relating to amphiphilic or amphoteric properties of peptides produced by proteolysis. 

The synthesis of peptides by enzymatic hydrolysis of proteins was carried out with gas-vortex gradientless bioreactor of type BIOK-022. As enzymes were used pepsin and trypsin. Initial concentration of the protein substrates was 20% on weight. Temperature of the synthesis was 36-40 C. Synthesis was carried out during 1 h. Received peptides molecular weight was 800-1100 g/mol of titration method with formalin [2],... 

---