Abstract: The present invention provides, as a method of analyzing the C-terminal amino acid sequence of a peptide with use of reaction technique for successively releasing the C-terminal amino acids, in which undesirable side reactions, such as cleavage of a peptide bond at the middle of the peptide, can be prevented and chemical treatments therein can be carried out under widely applicable conditions in the course of successive release of the C-terminal amino acids from a peptide, such a method comprising steps of dehydrating the gel on which a target peptide that has been separated by gel electrophoresis is held in the bound state; immersing it in a mixture solution of an alkanoic acid anhydride added with a small amount of a perfluoroalkanoic acid in a dipolar aprotic solvent to re-swell the gel carrier, forming a 5-oxazolone structure, at a temperature chosen in the range of from 30° C. to 80° C.

Abstract: The present invention provides, as for a method for analyzing the C-terminal amino acid sequence of a peptide by using a reaction for successively releasing the C-terminal amino acids of the peptide, which method can suppress, when successively releasing the C-terminal amino acids of a peptide of long amino acid length, such a undesirable side reaction as cleavage of peptide bond in the intermediate position of the peptide and can carry out the chemical treatment thereof under widely applicable conditions, a following method wherein a dry sample of a peptide with long amino acid length is beforehand subjected to an N-acylation treatment; by using a reaction reagent where an alkanoic acid anhydride is combined with a small amount of a perfluoroalkanoic acid, successive release of C-terminal amino acids is conducted under mild conditions; a hydrolysis treatment is applied; then, selective fragmentization at site of arginine residue is performed by digestion by trypsin; thereafter, decreases in molecular weight

Abstract: The present invention provides a method for analyzing the C-terminal amino acid sequence of a peptide by applying reaction technique for successively releasing the C-terminal amino acids therefrom, which method can suppress, when releasing the C-terminal amino acids of the peptide in sequence, such as an undesirable side reaction as cleavage of peptide bond in the intermediate position of the peptide, and allows to carry out the chemical treatment thereof under widely applicable conditions. In the method according to the present invention, an alkanoic acid anhydride and a perfluoroalkanoic acid both of vapor phase, which are supplied from a mixture containing an alkanoic acid anhydride with a small amount of a perfluoroalkanoic acid added thereto, are allowed to act on a dry sample of the peptide to be examined in a dry atmosphere at a temperature chosen in a range of 15 to 60° C.

Abstract: In a method for efficiently analyzing a posttranslational modification of a protein using no enzyme, a protein or peptide to be analyzed is reacted with an acid (a thioester or hydrazine) under certain conditions. This makes it possible to detect variously modified states of a protein or peptide, whereby the identification of each specific modifying group and the position of each modified amino acid can be efficiently analyzed using a chemical method and a mass spectrometric apparatus.

Abstract: The present invention provides, as for a method for analyzing the C-terminal amino acid sequence of a peptide by using a reaction for successively releasing the C-terminal amino acids of the peptide, which method can suppress, when successively releasing the C-terminal amino acids of a peptide of long amino acid length, such a undesirable side reaction as cleavage of peptide bond in the intermediate position of the peptide and can carry out the chemical treatment thereof under widely applicable conditions, a following method wherein a dry sample of a peptide with long amino acid length is beforehand subjected to an N-acylation treatment; by using a reaction reagent where an alkanoic acid anhydride is combined with a small amount of a perfluoroalkanoic acid, successive release of C-terminal amino acids is conducted under mild conditions; a hydrolysis treatment is applied; then, selective fragmentization at site of arginine residue is performed by digestion by trypsin; thereafter, decreases in molecular weight

Abstract: The present invention provides, as a method of analyzing the C-terminal amino acid sequence of a peptide with use of reaction technique for successively releasing the C-terminal amino acids, in which undesirable side reactions, such as cleavage of a peptide bond at the middle of the peptide, can be prevented and chemical treatments therein can be carried out under widely applicable conditions in the course of successive release of the C-terminal amino acids from a peptide, such a method comprising steps of dehydrating the gel on which a target peptide that has been separated by gel electrophoresis is held in the bound state; immersing it in a mixture solution of an alkanoic acid anhydride added with a small amount of a perfluoroalkanoic acid in a dipolar aprotic solvent to re-swell the gel carrier, forming a 5-oxazolone structure, at a temperature chosen in the range of from 30° C. to 80° C.

Abstract: The present invention provides a method for analyzing the C-terminal amino acid sequence of a peptide by applying reaction technique for successively releasing the C-terminal amino acids therefrom, which method can suppress, when releasing the C-terminal amino acids of the peptide in sequence, such a undesirable side reaction as cleavage of peptide bond in the intermediate position of the peptide, and allows to carry out the chemical treatment thereof under widely applicable conditions. In the method according to the present invention, an alkanoic acid anhydride and a perfluoroalkanoic acid both of vapor phase, which are supplied from a mixture containing an alkanoic acid anhydride with a small amount of a perfluoroalkanoic acid added thereto, are allowed to act on a dry sample of the peptide to be examined in a dry atmosphere at a temperature chosen in a range of 15 to 60° C.

Abstract: In a method for efficiently analyzing a posttranslational modification of a protein using no enzyme, a protein or peptide to be analyzed is reacted with an acid (a thioester or hydrazine) under certain conditions. This makes it possible to detect variously modified states of a protein or peptide, whereby the identification of each specific modifying group and the position of each modified amino acid can be efficiently analyzed using a chemical method and a mass spectrometric apparatus.