Data-independent liquid chromatography/mass spectrometry (LC/MS^E ) detection and quantification of the secreted Apium graveolens pathogen defense protein mannitol dehydrogenase

Plant cells secrete a wide variety of defense-related proteins into the extracellular space or apoplast in response to pathogen attack. One of these, mannitol dehydrogenase (MTD), is normally a cytoplasmic enzyme whose primary role is the regulation of intracellular levels of the sugar alcohol mannitol in plants. Recent immunological and biochemical evidence, however, suggests that MTD is also secreted into the apoplast in response to pathogen...