title: Ultraviolet radiation induces stress in etiolated Landoltia punctata, as evidenced by the presence of alanine, a universal stress signal: a ¹⁵N NMR study.
abstract: Analysis with (15) N NMR revealed that alanine, a universal cellular stress signal, accumulates in etiolated duckweed plants exposed to 15-min pulsed UV light, but not in the absence of UV irradiation. The addition of 10 mm vitamin C, a radical scavenger, reduced alanine levels to zero, indicating the involvement of free radicals. Free D-alanine was detected in (15) N NMR analysis of the chiral amino acid content, using D-tartaric acid as solvent. The accumulation of D-alanine under stress conditions presents a new perspective on the biochemical processes taking place in prokaryote and eukaryote cells.
authors.affiliation: Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: E B-I
authors.initials: EB
authors.lastname: Monselise
authors.forename: A
authors.initials: A
authors.lastname: Levkovitz
authors.forename: D
authors.initials: D
authors.lastname: Kost
mesh_terms: D000409:Alanine / Q000378:metabolism*; D029064:Araceae / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects*; D001205:Ascorbic Acid / Q000494:pharmacology; D064527:Etiolation / Q000187:drug effects / Q000528:radiation effects*; D009682:Magnetic Resonance Spectroscopy; D009587:Nitrogen Isotopes; D012996:Solutions; D013312:Stress, Physiological / Q000187:drug effects / Q000528:radiation effects*; D013644:Tartrates / Q000494:pharmacology; D014466:Ultraviolet Rays
chemical_list: D009587:Nitrogen Isotopes; D012996:Solutions; D013644:Tartrates; D000409:Alanine; D001205:Ascorbic Acid; C029768:tartaric acid
keywords: 15N-NMR analysis; D-alanine accumulation; etiolated plants; nitrogen assimilation; radical scavenger; vitamin C