title: The source of "fairy rings": 2-azahypoxanthine and its metabolite found in a novel purine metabolic pathway in plants.
abstract: Rings or arcs of fungus-stimulated plant growth occur worldwide; these are commonly referred to as "fairy rings". In 2010, we discovered 2-azahypoxanthine (AHX), a compound responsible for the fairy-ring phenomenon caused by fungus; AHX stimulated the growth of all the plants tested. Herein, we reveal the isolation and structure determination of a common metabolite of AHX in plants, 2-aza-8-oxohypoxanthine (AOH). AHX is chemically synthesized from 5-aminoimidazole-4-carboxamide (AICA), and AHX can be converted into AOH by xanthine oxidase. AICA is one of the members of the purine metabolic pathway in animals, plants, and microorganisms. However, further metabolism of AICA remains elusive. Based on these results and facts, we hypothesized that plants themselves produce AHX and AOH through a pathway similar to the chemical synthesis. Herein, we demonstrate the existence of endogenous AHX and AOH and a novel purine pathway to produce them in plants.
authors.affiliation: Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529 (Japan).
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Choi
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ohnishi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yamakawa
authors.forename: Shogo
authors.initials: S
authors.lastname: Takeda
authors.forename: Shuhei
authors.initials: S
authors.lastname: Sekiguchi
authors.forename: Waki
authors.initials: W
authors.lastname: Maruyama
authors.forename: Kimiko
authors.initials: K
authors.lastname: Yamashita
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Suzuki
authors.forename: Akio
authors.initials: A
authors.lastname: Morita
authors.forename: Takashi
authors.initials: T
authors.lastname: Ikka
authors.forename: Reiko
authors.initials: R
authors.lastname: Motohashi
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kiriiwa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tobina
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Asai
authors.forename: Shinji
authors.initials: S
authors.lastname: Tokuyama
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Hirai
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yasuda
authors.forename: Keiichi
authors.initials: K
authors.lastname: Noguchi
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Asakawa
authors.forename: Shimpei
authors.initials: S
authors.lastname: Sugiyama
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Kan
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kawagishi
mesh_terms: D018360:Crystallography, X-Ray; D007042:Hypoxanthines / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D008968:Molecular Conformation; D012275:Oryza / Q000378:metabolism*; D011687:Purines / Q000737:chemistry / Q000378:metabolism*; D014969:Xanthine Oxidase / Q000378:metabolism
chemical_list: D007042:Hypoxanthines; D011687:Purines; D014969:Xanthine Oxidase; C012759:2-azahypoxanthine; C030985:purine
keywords: biosynthesis; fairy rings; microarrays; natural products; purine metabolism