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Hideyuki Matsuura - One of the best experts on this subject based on the ideXlab platform.
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Feeding experiment using uniformly 13C-labeled α-linolenic acid supports the involvement of the decarboxylation mechanism to produce cis-jasmone in Lasiodiplodia theobromae.
Bioscience biotechnology and biochemistry, 2019Co-Authors: Ryo Matsui, Kosaku Takahashi, Kisumi Takiguchi, Kazuhiko Matsuda, Hideyuki MatsuuraAbstract:In our previous report, it was found that Lasiodiplodia theobromae produced cis-jasmone via partially utilizing the biosynthetic pathway of JA. A feeding experiment using uniformly 13C-labeled α-li...
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Biosynthesis of Resorcylic Acid Lactone (5S)-5-Hydroxylasiodiplodin in Lasiodiplodia theobromae
Bioscience biotechnology and biochemistry, 2009Co-Authors: Takasumi Kashima, Kosaku Takahashi, Hideyuki Matsuura, Kensuke NabetaAbstract:An administration study of 2H-labeled precursors showed that the 9-hydroxydecanoyl unit, the acyl intermediate of lasiodiplodin (1), was also the intermediate of (5S)-5-hydroxylasiodiplodin (2) in Lasiodiplodia theobromae. The incorporation of [O-methyl-2H3]-lasiodiplodin (6) into 2 indicated that hydroxylation at C-5 occurred after cyclization.
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Isolation and Structural Elucidation of a New Cyclohexenone Compound from Lasiodiplodia theobromae
Bioscience biotechnology and biochemistry, 2009Co-Authors: Naoki Kitaoka, Kensuke Nabeta, Hideyuki MatsuuraAbstract:A new cyclohexenone compound was isolated as a mixture of enantiomers from a culture filtrate of Lasiodiplodia theobromae. The relative structure was determined to be 4,5-dihydroxy-3-methyl-cyclohex-2-enone on the basis of MS, 1H-NMR, and 13C-NMR spectroscopic analyses, including 2D-NMR experiments. Resolution of the enantiomers was conducted by a coupling reaction with (S)-MTPA-Cl followed by HPLC separation.
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Biosynthesis of resorcylic acid lactone lasiodiplodin in Lasiodiplodia theobromae
Bioscience biotechnology and biochemistry, 2009Co-Authors: Takasumi Kashima, Kosaku Takahashi, Hideyuki Matsuura, Kensuke NabetaAbstract:The biosynthesis of lasiodiplodin (1) and its (5S)-5-hydroxylated derivative (2) were investigated by the administration of 13C-labeled acetates to Lasiodiplodia theobromae. The labeling patterns of biosynthetically 13C-labeled 1 and 2 were determined by 13C-NMR and INADEQUATE spectra, demonstrating the octaketide origins of 1 and 2. Taking into account the biosynthetic study of resorcylic acid lactones, the involvement of highly reduced acyl intermediates in the biosynthesis of lasiodiplodins was presumed; thus, we synthesized 2H-labeled hypothetical acyl intermediates of 1, 9-hydroxydecanoic acid (4) and its N-acetylcysteamine thioester (SNAC, 5). When L. theobromae was incubated with 5 mM of a 2H-labeled intermediate, the 2H-label from the intermediate was incorporated at the expected position of 1. These incorporation studies revealed that 1 was produced via a pathway which closely resembles that of resorcylic acid lactone biosynthesis.
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new potato micro tuber inducing cyclohexene compounds related to theobroxide from Lasiodiplodia theobromae
Bioscience Biotechnology and Biochemistry, 2008Co-Authors: Ryo Takei, Kosaku Takahashi, Hideyuki Matsuura, Kensuke NabetaAbstract:Two new cyclohexene compounds related to theobroxide (3) were isolated from the mycelia of Lasiodiplodia theobromae OCS71. The structures of these compounds were determined to be (4S,5S)-4,5-dihydroxy-2-methyl-cyclohex-2-enone (1) and (3aS,4R,5S,7aR)-4,5-dihydroxy-7-methyl-3a,4,5,7a-tetrahydrobenzo[1,3]dioxol-2-one (2) by means of spectroscopic analyses and chemical correlation to 3. Compound 2 was shown to take up the carbonate ion to form a carbonic acid ester non-enzymatically. The compounds also showed potato micro-tuber-inducing activities at a concentration of 10−3 M, using a culture of single-node segments of potato stems in vitro.
Teruhiko Yoshihara - One of the best experts on this subject based on the ideXlab platform.
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Novel potato micro-tuber-inducing compound, (3R,6S)-6-hydroxylasiodiplodin, from a strain of Lasiodiplodia theobromae.
Bioscience biotechnology and biochemistry, 2005Co-Authors: Kosaku Takahashi, Hideyuki Matsuura, Teruhiko YoshiharaAbstract:A novel potato micro-tuber-inducing compound was isolated from the culture broth of Lasiodiplodia theobromae Shimokita 2. The structure of the isolated compound was determined as (3R,6S)-6-hydroxylasiodiplodin by means of spectroscopic analyses, the modified Mosher method, and chemical conversion. The compound showed potato micro-tuber-inducing activity at a concentration of 10−4 M, using the culture of single-node segments of potato stems in vitro.
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syntheses of β resorcylic acid derivatives novel potato micro tuber inducing substances isolated from Lasiodiplodia theobromae
Tetrahedron, 2001Co-Authors: Qing Yang, Hiroaki Toshima, Teruhiko YoshiharaAbstract:Abstract The syntheses of β-resorcylic acid derivatives 1 and 2, isolated from fungus Lasiodiplodia theobromae, and their dimethyl ethers were accomplished. (R)-(−)-1,3-Butanediol was used as a chiral source of the side chain C6-synthon. The dianion of the benzoic acid moiety was alkylated with C6-bromide to give the desired skeleton. Several β-resorcylic acid derivatives including 1 and 2 were synthesized via hydrogenation, lactonization, demethylation and esterification. The (R)-configuration of the stereogenic center in the side chain was proved by this synthesis. It is confirmed that two phenolic hydroxy groups are required for 1 and 2 to exhibit potato micro-tuber inducing activity.
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Novel resorcinol derivatives from Lasiodiplodia theobromae.
Zeitschrift für Naturforschung C, 2000Co-Authors: Yang Qing, Maki Asai, Teruhiko YoshiharaAbstract:Abstract Two novel resorcinol derivatives were isolated from the mycelium of Lasiodiplodia theobromae IFO 31059 as potato micro-tuber inducing compounds. Their structures were established by spectroscopic methods as ethyl (6′R)-2,4-dihydroxy-6-(6′-hydroxyheptyl)benzoate (8) and isobutyl (6′R)-2.4-dihydroxy-6-(6′-hydroxyheptyl)benzoate (9). The absolute stereochemistry of the asymmetric center of (8) was determined by an advanced Mosher method.
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Potato micro-tuber inducing hydroxylasiodiplodins from Lasiodiplodia theobromae.
Phytochemistry, 2000Co-Authors: Qing Yang, Hideyuki Matsuura, Maki Asai, Teruhiko YoshiharaAbstract:Three hydroxylasiodiplodins were isolated from the mycelium extracts of Lasiodiplodia theobromae IFO 31059; and their structures were identified as (3R),(4S)-4-hydroxylasiodiplodin, (3R),(6R)-6-hydroxy-de-O-methyllasiodiplodin and (3R),(5R)-5-hydroxy-de-O-methyllasiodiplodin. All showed potato micro-tuber inducing activity.
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Three lasiodiplodins from Lasiodiplodia theobromae ifo 31059
Phytochemistry, 1998Co-Authors: Hideyuki Matsuura, Kaoru Nakamori, Teruhiko Yoshihara, El-sayed A. Omer, Chiaki Hatakeyama, Akitami IchiharaAbstract:Abstract Three new fungal metabolites were isolated from the culture filtrate of the fungus, Lasiodiplodia theobromae IFO 31059 and identified as (5 R ) and (5 S ) 5-hydroxylasiodiplodins and 5-oxolasiodiplodin. The first two showed weak potato micro-tuber inducing activities, although only at very high dosage levels.
Akitami Ichihara - One of the best experts on this subject based on the ideXlab platform.
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Novel Cyclohexene Compound from Lasiodiplodia theobromae IFO 31059.
Bioscience biotechnology and biochemistry, 1998Co-Authors: Hideyuki Matsuura, Akitami Ichihara, Naomi Obara, Noriko Chisaka, Teruhiko YoshiharaAbstract:A novel cyclohexene compound (1), which is structurally related to theobroxide (2), was isolated from a culture filtrate of the fungus, Lasiodiplodia theobromae IFO 31059. The potato micro-tuber-inducing activity of this compound was observed at a concentration of 10-3 M in the medium, whereas theobroxide (2) showed its activity at 10-5 M.
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Three lasiodiplodins from Lasiodiplodia theobromae ifo 31059
Phytochemistry, 1998Co-Authors: Hideyuki Matsuura, Kaoru Nakamori, Teruhiko Yoshihara, El-sayed A. Omer, Chiaki Hatakeyama, Akitami IchiharaAbstract:Abstract Three new fungal metabolites were isolated from the culture filtrate of the fungus, Lasiodiplodia theobromae IFO 31059 and identified as (5 R ) and (5 S ) 5-hydroxylasiodiplodins and 5-oxolasiodiplodin. The first two showed weak potato micro-tuber inducing activities, although only at very high dosage levels.
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Potato micro-tuber inducing substances from Lasiodiplodia theobromae
Phytochemistry, 1994Co-Authors: Kaoru Nakamori, Hideyuki Matsuura, Teruhiko Yoshihara, Akitami Ichihara, Yasunori KodaAbstract:Abstract Three potato-tuber inducing substances were isolated from Lasiodiplodia theobromae IFO 31059, and their structures identified as mellein, jasmonic acid and a previously unrecorded cyclohexene named theobroxide.
Kensuke Nabeta - One of the best experts on this subject based on the ideXlab platform.
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Biosynthesis of Resorcylic Acid Lactone (5S)-5-Hydroxylasiodiplodin in Lasiodiplodia theobromae
Bioscience biotechnology and biochemistry, 2009Co-Authors: Takasumi Kashima, Kosaku Takahashi, Hideyuki Matsuura, Kensuke NabetaAbstract:An administration study of 2H-labeled precursors showed that the 9-hydroxydecanoyl unit, the acyl intermediate of lasiodiplodin (1), was also the intermediate of (5S)-5-hydroxylasiodiplodin (2) in Lasiodiplodia theobromae. The incorporation of [O-methyl-2H3]-lasiodiplodin (6) into 2 indicated that hydroxylation at C-5 occurred after cyclization.
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Isolation and Structural Elucidation of a New Cyclohexenone Compound from Lasiodiplodia theobromae
Bioscience biotechnology and biochemistry, 2009Co-Authors: Naoki Kitaoka, Kensuke Nabeta, Hideyuki MatsuuraAbstract:A new cyclohexenone compound was isolated as a mixture of enantiomers from a culture filtrate of Lasiodiplodia theobromae. The relative structure was determined to be 4,5-dihydroxy-3-methyl-cyclohex-2-enone on the basis of MS, 1H-NMR, and 13C-NMR spectroscopic analyses, including 2D-NMR experiments. Resolution of the enantiomers was conducted by a coupling reaction with (S)-MTPA-Cl followed by HPLC separation.
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Biosynthesis of resorcylic acid lactone lasiodiplodin in Lasiodiplodia theobromae
Bioscience biotechnology and biochemistry, 2009Co-Authors: Takasumi Kashima, Kosaku Takahashi, Hideyuki Matsuura, Kensuke NabetaAbstract:The biosynthesis of lasiodiplodin (1) and its (5S)-5-hydroxylated derivative (2) were investigated by the administration of 13C-labeled acetates to Lasiodiplodia theobromae. The labeling patterns of biosynthetically 13C-labeled 1 and 2 were determined by 13C-NMR and INADEQUATE spectra, demonstrating the octaketide origins of 1 and 2. Taking into account the biosynthetic study of resorcylic acid lactones, the involvement of highly reduced acyl intermediates in the biosynthesis of lasiodiplodins was presumed; thus, we synthesized 2H-labeled hypothetical acyl intermediates of 1, 9-hydroxydecanoic acid (4) and its N-acetylcysteamine thioester (SNAC, 5). When L. theobromae was incubated with 5 mM of a 2H-labeled intermediate, the 2H-label from the intermediate was incorporated at the expected position of 1. These incorporation studies revealed that 1 was produced via a pathway which closely resembles that of resorcylic acid lactone biosynthesis.
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new potato micro tuber inducing cyclohexene compounds related to theobroxide from Lasiodiplodia theobromae
Bioscience Biotechnology and Biochemistry, 2008Co-Authors: Ryo Takei, Kosaku Takahashi, Hideyuki Matsuura, Kensuke NabetaAbstract:Two new cyclohexene compounds related to theobroxide (3) were isolated from the mycelia of Lasiodiplodia theobromae OCS71. The structures of these compounds were determined to be (4S,5S)-4,5-dihydroxy-2-methyl-cyclohex-2-enone (1) and (3aS,4R,5S,7aR)-4,5-dihydroxy-7-methyl-3a,4,5,7a-tetrahydrobenzo[1,3]dioxol-2-one (2) by means of spectroscopic analyses and chemical correlation to 3. Compound 2 was shown to take up the carbonate ion to form a carbonic acid ester non-enzymatically. The compounds also showed potato micro-tuber-inducing activities at a concentration of 10−3 M, using a culture of single-node segments of potato stems in vitro.
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biosynthesis of theobroxide and its related compounds metabolites of Lasiodiplodia theobromae
Phytochemistry, 2007Co-Authors: Ryo Takei, Kosaku Takahashi, Kensuke NabetaAbstract:Abstract Administration of 13 C labeled acetates ([1- 13 C], [2- 13 C] and [1,2- 13 C 2 ] to Lasiodiplodia theobromae showed the tetraketide origins of both theobroxide, a potato-tuber inducing substance { 1 , (1 S , 2 R , 5 S , 6 R )-3-methyl-7-oxa-bicyclo[4.1.0]hept-3-en-2,5-diol}) and its carbonyldioxy derivative { 2 , (1 S , 4 R , 5 S , 6 R )-7,9-dioxa-3-methyl-8-oxobicyclo [4.3.0]-2-nonene-4,5-diol}. The incorporation of acetate-derived hydrogen into 1 and 2 was studied using [2- 2 H 3 , 2- 13 C]acetate. Three and one deuterium atoms were incorporated at one methyl and epoxy carbons, respectively. The observed loss of deuterium atoms from the methyl group suggests a considerable amount of exchange from the methyl group of [2- 2 H 3 , 2- 13 C]acetate during biosynthesis of 1 and 2 . Incorporation of [1- 13 C]- and [1,2- 13 C 2 ]acetates indicates the carbonyl carbon of the carbonyldioxy derivative is derived from the carboxy carbon of the precursor.
Kaoru Nakamori - One of the best experts on this subject based on the ideXlab platform.
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Three lasiodiplodins from Lasiodiplodia theobromae ifo 31059
Phytochemistry, 1998Co-Authors: Hideyuki Matsuura, Kaoru Nakamori, Teruhiko Yoshihara, El-sayed A. Omer, Chiaki Hatakeyama, Akitami IchiharaAbstract:Abstract Three new fungal metabolites were isolated from the culture filtrate of the fungus, Lasiodiplodia theobromae IFO 31059 and identified as (5 R ) and (5 S ) 5-hydroxylasiodiplodins and 5-oxolasiodiplodin. The first two showed weak potato micro-tuber inducing activities, although only at very high dosage levels.
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Potato micro-tuber inducing substances from Lasiodiplodia theobromae
Phytochemistry, 1994Co-Authors: Kaoru Nakamori, Hideyuki Matsuura, Teruhiko Yoshihara, Akitami Ichihara, Yasunori KodaAbstract:Abstract Three potato-tuber inducing substances were isolated from Lasiodiplodia theobromae IFO 31059, and their structures identified as mellein, jasmonic acid and a previously unrecorded cyclohexene named theobroxide.
