Insulin aspart (AspB28 human insulin) derivatives formed in pharmaceutical solutions.

Purpose: To isolate and identify the main insulin aspart (AspB28 human insulin) derivatives formed in pharmaceuticals (pH 7.4 at 5 degrees C), to estimate rates of formation, and to determine their biologic potencies.

Methods: Insulin aspart derivatives have been isolated by reversed-phase high-performance liquid chromatography (RP-HPLC), and identified by RP-HPLC, peptide mapping, amino acid analysis, mass spectrometry.

N- and O-glycosylation and phosphorylation of the bar secretion leader derived from the barrier protease of Saccharomyces cerevisiae.

A secretion leader derived from a domain of the extracellular Barrier protease of the yeast Saccharomyces cerevisiae has been expressed in wild-type and in mnn1, mnn9, and mnn1 mnn9 glycosylation mutant strains of S. cerevisiae. Structural comparison of the extracellular leader by mass spectrometry, peptide mapping, and elementary analysis proved that all strains produced a heterogeneous, heavily glycosylated polypeptide of 161 amino acids with both N- and O-glycosylation and phosphorylation.