![]() ![]() ![]() The compound of claim 1, wherein Y is a residue of a hyaluronan, and X is -O-, wherein at least one hydroxyl group is substituted with -CH 2CH 2SH. The compound of claim 1, wherein X is -O- or -NH. The compound of claim 1, wherein R is CH 2CH 2. The compound of claim 1, wherein R is selected from the group consisting of CH 2CH 2, CH 2CH 2CH 2, CH 2CHR 1, CHR 1CHR 1, C(R 1) 2CHR 1 and C(R 1) 2C(R 1) 2, wherein R 1 is an alkyl group. The compound of claim 6, wherein from one primary C-6 hydroxyl group of the N-acetyl-glucosamine residue to about 100% of the primary C-6 hydroxyl groups of the N-acetyl-glucosamine residue are substituted with the group -RSH. The compound of claim 5, wherein at least one secondary hydroxyl group is substituted with the group -RSH. The compound of claim 1, wherein Y comprises a residue of a N-acetyl-glucosamine, wherein at least one primary C-6 hydroxyl group of the N-acetyl-glucosamine residue is substituted with the group -RSH. The compound of claim 1, wherein Y comprises a residue of hyaluronan. The compound of claim 1, wherein the macromolecule is a protein, selected from the group consisting of a naturally-occurring protein, a recombinant protein, an extracellular matrix protein, a chemically-modified extracellular matrix protein, a partially hydrolyzed derivative of an extracellular matrix protein, and a genetically engineered protein. The compound of claim 1, wherein the polysaccharide is selected from the group consisting of hyaluronan, chondroitin sulfate, dermatan, heparan, heparin, dermatan sulfate, heparan sulfate, alginic acid, pectin, chitosan and carboxymethylcellulose. A compound comprising the formula I Y-X-R-SH I wherein: Y is a residue of a macromolecule selected from the group consisting of an oligonucleotide, a nucleic acid or a metabolically stabilized analogue thereof, a polypeptide, a glycoprotein, a glycolipid, a polysaccharide, a protein and a glycosaminoglycan X is -O-, -S-, -NH-, or -NR′- R′ is C 1-5 alkyl and R is a substituted or unsubstituted C 2 or C 3 alkylene group. The dansyl-Edman method described here was originally introduced by Hartley ( 1).What is claimed: 1. Although the dansyl-Edman method results in successively less peptide being present at each cycle of the Edman degradation, this loss of material is compensated for by the considerable sensitivity of the dansyl method for identifying N-terminal amino acids. Instead, a small fraction (5%) of the remaining peptide is taken and the newly liberated N-terminal amino acid determined in this sample by the dansyl method ( see Chapter 20). Following the cleavage step the thiazolinone is extracted, but rather than being converted to the PTH derivative it is discarded. The dansyl-Edman method for peptide sequencing described here is based on the Edman degradation, but with the following modifications. This is known as the direct Edman degradation and is, for example, the method used in an automated sequencing machine. The PTH amino acid is then identified, normally by reverse-phase HPLC. The thiazolinone is extracted into an organic solvent, dried down, and then converted to the more stable phenylthiohydantoin (PTH) derivative (the conversion step). The N-terminal amino acids is therefore released as a derivative (the thiazolinone). g., trifluoracetic acid), which results in cleavage of the peptide bond between the first and second amino acid. The sample is then dried and treated with an anhydrous acid (e. In the first step (the coupling reaction) phenylisothocyanate (PITC) reacts with the N-terminal amino group of the peptide or protein. The overall reaction sequence is shown in Fig. The Edman degradation is a series of chemical reactions that sequentially removes N-terminal amino acids from a peptide or protein. ![]()
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