Exploration of Beer Proteome Using OFFGEL Prefractionation in Combination with Two-Dimensional Gel Electrophoresis with Narrow pH Range Gradients

Two-dimensional gel electrophoresis in combination with
mass spectrometry
has already been applied successfully to study beer proteome. Due
to the abundance of protein Z in beer samples, prefractionation techniques
might help to improve beer proteome coverage. Proteins from four lager
beers of different origins were separated by two-dimensional electrophoresis
(2-DE) followed by tandem mass spectrometric analysis. Initially 52
proteins mostly from Hordeum vulgare (22 proteins) and Saccharomyces species (25 proteins)
were identified. Preparative isoelectric focusing by OFFGEL Fractionator
was applied prior to 2-DE to improve its resolution power. As a result
of this combined approach, a total of 70 beer proteins from Hordeum vulgare (30 proteins), from Saccharomyces species (31 proteins), and from other sources (9 proteins) were
identified. Of these, 37 proteins have not been previously reported
in beer samples.