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A.-CH. BERGMAN et aI.
mated size of the protein substrate. The computer screens available protein and
nucleic acid databases and the output is generated in the form of a list with possible candidates. If the protein is not in the database, the peptide extract can be
further analyzed with tandem mass spectrometry (MS/MS, Fig. 6.1) using the
nanoelectrospray ion source (Wilm and Mann, 1996). Via collision-induced disI-D/2-D
Gel electrophoresis
I In-gel digestion
I
I Fragments
I Mass spectrometry I
/ \
MS/MS
I Microblotter I
j
I Isolated peptide I
j
High-sensitivity
Edman
degradation
Electroblotting
(PVDF)
j
j
High-sensitivity
Edman
degradation
Fig. 6.1. Schematic outline of the recommended strategy for characterization of gel separated proteins (cf. text)