Beginning about October 1, the Proteomics Shared Resource will be offering has a new mass spec instrument that should greatly increase the productivity of proteomics experiments. Specifically, this instrument is a ThermoFisher LTQ Velos linear ion trap mass spectrometer with an electron transfer dissociation source. It was awarded through an S10 shared equipment grant from NCRR.
This instrument more than doubles the number of proteins that can be identified in complex mixtures. This extreme sensitivity will be especially useful to investigators who are sample- limited. The electron transfer dissociation source on the new instrument will also facilitate analysis of post-translational modifications. For example, sites of phosphorylation are difficult to detect using the more typical collision-induced dissociation used on older instruments, which causes a loss of the phosphate group from peptides, resulting in poor fragmentation of peptide bonds and loss of sequence information. In contrast, the new electron transfer dissociation source is capable of fragmenting peptides to produce sequence information but will not cause phosphate loss from the peptide. What does this mean for you? Your phosphorylation sites will be more successfully localized.
But wait! There’s more! The electron transfer dissociation source will also allow analysis of larger peptide fragments than is possible when using collision-induced dissociation. Even better, these two approaches can be combined when analyzing protein digests to recover a far greater percentage of the protein’s sequence and increase the likelihood of finding modification sites.
Best of all, the new instrument will increase the proteomics core’s sample throughput. Their older LTQ instrument was being used around the clock and 7 days a week. The new instrument will allow the continued growth of the core and decrease turn-around time for results.