Localization and Composition of Fructans in Stem and Rhizome of Agave tequilana Weber var. azul

20 de enero de 2021

Te invitamos a leer: “Localization and Composition of Fructans in Stem and Rhizome of Agave tequilana Weber var. azul” publicado en Frontiers, trabajo de Arely V. Pérez López, June Simpson, Alan D. Gomez Vargas del Departamento de Ingeniería Genética del Cinvestav Irapuato; Malcolm R. Clench del Centre for Mass Spectrometry Imaging de Sheffield Hallam University y José J. Ordaz Ortiz, profesor investigador del Laboratorio de Metabolómica y Espectrometría de Masas de la UGA-Langebio.

Autores: Arely V. Perez-Lopez¹, June Simpson¹, Malcolm R. Clench², Alan D. Gomez-Vargas¹ and Jose J. Ordaz-Ortiz³.

1. Department of Genetic Engineering. CINVESTAV Unidad Irapuato, Irapuato, Mexico.
2. Centre for Mass Spectrometry Imaging, Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, United Kingdom.
3. Metabolomics and Mass Spectrometry Laboratory. National Laboratory of Genomics for Biodiversity. Unidad de Genómica Avanzada (CINVESTAV), lrapuato, Mexico.

Felicitamos al estudiantado y profesorado que contribuyeron en esta investigación por su arduo trabajo.

Abstract: Methodology combining mass spectrometry imaging (MSI) with ion mobility separation (IMS) has emerged as a biological imaging technique due to its versatility, sensitivity and label-free approach, This technique has been shown to separate isomeric compounds such as lipids, amino acids, carboxylic acids and carbohydrates. This report describes mass spectrometry imaging in combination with traveling-wave ion mobility separation and matrix-assisted laser desorption/ionization (MALDI). Positive ionization mode was used to locate fructans on tissue printed sections of Agave rhizome and stem tissue and distinguished fructan isoforms. Here we show the location of fructans ranging from DP3 to DP17 to be differentially abundant across the stem tissue and for the first time, experimental collision cross sections of endogenous fructan structures have been collected, revealing at least two isoforms for fructans of DP4, DPS, DP6, DP?, DPS, DP10, and DP11 . This demonstrates that complex fructans such as agavins can be located and their isoforms resolved using a combination of MALDI, IMS, and MSI, without the need for extraction or derivatization. Use of this methodology uncovered patterns of fructan localization consistent with functional differences where higher DP fructans are found toward the central section of the stem supporting a role in long term carbohydrate storage whereas lower DP fructans are concentrated in the highly vascularized central core of rhizomes supporting a role in mobilization of carbohydrates from the mother plant to developing offsets. Tissue specific patterns of expression of genes encoding enzymes involved in fructan metabolism are consistent with fructan structures and localization.

Keywords: fructan, Agave tequilana, mass spectrometry imaging, ion mobility separation, degree of polymerization, fructan isoform, fructan metabolism, collision cross section.