Analysis of Photorespiratory Intermediates Under Transient Conditions by Mass Spectrometry.

Photorespiration is an essential process of phototropic organisms caused by the limited ability of rubisco to distinguish between CO2 and O2. To understand the metabolic flux through the photorespiratory pathway, we combined a mass spectrometry-based approach with a shift experiment from elevated CO2 (3000 ppm) to ambient CO2 (390 ppm). Here, we describe a protocol for quantifying photorespiratory intermediates, starting from plant cultivation through extraction and evaluation.