Analytical Chemistry Tools:
LC-Tandem MS/MS: The Dismukes lab is equipped with commercial QQQ and Q-TOF mass spectrometers coupled to LC chromatographic separation systems for nano-flow LC and 2D nano-cube LC. These are among the most sensitive mass spectrometers available (lod = Femtogram). They feature robust operation and amenability towards the detection of small, polar metabolites. The use of isotopic-labeled inputs also allows for the direct time-resolved monitoring of pathway fluxes. Chemical extraction parameters have been optimized for Synechococcus sp. PCC7002. Cellular metabolites are extracted by ice cold extraction buffer. The extracts are subsequently separated using Reversed-phase Ion-pairing (RIP) chromatography, the effluent of which is analyzed using a Agilent 6400 Series Triple Quadrupole (QQQ) mass spectrometer. Targeted metabolites are detected via predetermined mass breakdown channels, and concentrations are estimated based on compound-specific calibration curves.