Record Details
Field | Value |
---|---|
Title | Preparation and properties of polyglycyl insulin |
Names |
Wu, Lily Henson Liu
(creator) Becker, Robert R. (advisor) |
Date Issued | 1966-12-07 (iso8601) |
Note | Graduation date: 1967 |
Abstract | In order to understand more about insulin behavior in solution, Zn-free insulin was modified by adding polyglycyl chains to the molecule and then observing the effect of the peptide on the behavior of insulin under various conditions. NCA-glycine (N-Carboxyglycine anhydride) of high purity was reacted with Zn-free insulin in aqueous solution to form polyglycyl insulin. It was found by dinitrophenylation, formaldehyde titration and amino acid analysis that two N-terminal amino acids and one lysine were acylated. The length of the added glycine peptide varied with the modification conditions. Biological tests indicated that the polyglycyl insulin retained its biological activity, except for highly substituted derivatives. The derivatives were resistant to trypsin digestion. Polyglycyl insulin was more soluble than native insulin. The solubility varied with pH in a manner similar to native insulin, but was about three times more soluble between pH 4 and pH 6. Thin film dialysis experiments indicated that the polyglycyl insulin was heterogeneous with respect to the length of attached glycine peptides. Insulin forms aggregates under various conditions. In the present study the gel filtration technique was used to analyze the aggregation state of modified insulins. The polyglycyl-insulin modified as its monomer behaved the same as the native insulin. How ever, when it was modified as the dimer, the product remained as dimer under conditions where native insulin could be converted to monomer. |
Genre | Thesis/Dissertation |
Topic | Insulin |
Identifier | http://hdl.handle.net/1957/47267 |