An insulin with the native sequence but virtually no activity.

A Wollmer; G Gilge; D Brandenburg; H G Gattner

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PubMed · 8011179

An insulin with the native sequence but virtually no activity.

A Wollmer·G Gilge·D Brandenburg·H G Gattner

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Abstract

The B24-B25 peptide bond of insulin was replaced by an ester bond. To our knowledge this is the first replacement of a main chain atom reported for the hormone. It is meant to eliminate a structurally important H-bond between the imino group of B25 and the carbonyl oxygen of A19, and consequently to enhance detachment of the C-terminal B chain from the underlying A chain. On the basis of independent experimental evidence this very conformational change is believed to be a prerequisite for receptor binding. It was thus anticipated that increased flexibility would increase receptor binding and activity. Intriguingly, porcine [B24-B25 CO-O]insulin (depsi-insulin) and likewise [B24-B25 CO-O]des-(B26-B30)insulin-B25-amide (depsi-DPI-amide) were found to be only 3-4% potent.

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Adipocytes Animals Circular Dichroism Hydrogen Bonding Insulin Protein Structure, Secondary Receptor, Insulin Spectrophotometry, Ultraviolet Swine Journal Article

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A Wollmer, G Gilge, D Brandenburg, H G Gattner. 1994. An insulin with the native sequence but virtually no activity.. https://pubmed.ncbi.nlm.nih.gov/8011179/

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