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Comparative gas phase and pulsed liquid phase sequencing on a modified Applied Biosystems 477A sequencer.

M Baumann
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Abstract

A simple and inexpensive modification of the Applied Biosystems 477A sequencer, to run in the pulsed liquid-phase and in the gas-phase mode of the Edman chemistry, is described. This modification is especially useful for sequencing samples on polyvinylidene difluoride (PVDF) membranes. Additional carriers are required if a sample on a PVDF membrane is sequenced with the pulsed liquid-phase degradation program of the 477A. In the gas-phase mode no such carriers are needed. This eliminates time-consuming preconditioning sequencer cycles and reduces the sequencer background. In addition, initial coupling yields in the gas-phase mode exceeded those in the pulsed liquid-phase mode, whereas the average repetitive yields were similar. Samples spotted onto glass fiber filters pretreated with polybrene and samples spotted or electroblotted onto PVDF membranes were examined. A number of advantages of the gas-phase mode are presented.

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Amino Acid SequenceElectrophoresis, Polyacrylamide GelGasesGlassHexadimethrine BromideLactoglobulinsMembranes, ArtificialMolecular Sequence DataMuramidasePolyvinylsProteinsTrifluoroacetic AcidFluorocarbon PolymersComparative StudyJournal Article

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M Baumann. 1990-11-01. Comparative gas phase and pulsed liquid phase sequencing on a modified Applied Biosystems 477A sequencer.. https://doi.org/10.1016/0003-2697(90)90181-8

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