Hiltunen Lea H, Laakso Into, Chobot Vladimír, Hakala Kati S, Weckman Anja, Valkonen Jari P T
Department of Applied Biology, University of Helsinki, P.O. Box 27, FI-00014, Finland.
J Agric Food Chem. 2006 May 3;54(9):3372-9. doi: 10.1021/jf060270m.
Plant-pathogenic Streptomyces species produce a variety of different phytotoxic 4-nitroindol-3-yl-containing 2,5-dioxopiperazines (thaxtomins) that induce scab symptoms on potato tubers (Solanum tuberosum). The possible mutual synergistic or antagonistic effects of thaxtomins are unknown. Modified methodology using column chromatography allowed the purification of thaxtomin A in large quantities (27 mg, HPLC purity of 97%). Thaxtomin A ortho isomer, thaxtomin B, and C-14 deoxythaxtomin B (thaxtomin D) were also purified. All four compounds induced similar symptoms of reduced root and shoot growth, root swelling (10-200 ppb), or necrosis (200-1000 ppb) on micropropagated in vitro cultures of potato. The scab-resistant potato cvs. Sabina and Nicola were more tolerant to thaxtomins than was the scab-susceptible cv. Matilda. Thaxtomins applied in combinations showed additive effects but no synergism, whereas thaxtomins A and B displayed antagonism with thaxtomin A ortho isomer.
植物致病链霉菌物种产生多种不同的含4-硝基吲哚-3-基的具有植物毒性的2,5-二氧代哌嗪（thaxomins），这些物质会在马铃薯块茎（Solanum tuberosum）上引发疮痂症状。thaxomins可能存在的相互协同或拮抗作用尚不清楚。使用柱色谱的改良方法能够大量纯化thaxomin A（27毫克，HPLC纯度为97%）。thaxomin A邻位异构体、thaxomin B和C-14脱氧thaxomin B（thaxomin D）也得到了纯化。所有这四种化合物在马铃薯微繁殖离体培养物上均引发了类似的症状，即根和芽生长受抑制、根肿胀（10 - 200 ppb）或坏死（200 - 1000 ppb）。抗疮痂马铃薯品种Sabina和Nicola对thaxomins的耐受性高于感疮痂品种Matilda。组合施用thaxomins显示出相加效应但无协同作用，而thaxomins A和B与thaxomin A邻位异构体表现出拮抗作用。
