The biosynthesis of reticuline

Tewari, Shobha; Bhakuni, D. S.; Kapil, R. S.

doi:10.1039/c39750000554

Cited by 13 publications

(8 citation statements)

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“…This is also consistent with the sequence of 0-methylation of phenethylamine and tetrahydroisoquinolines in the biosynthesis of peyote alkaloids [18]. The observation that (R,S)-[1-3H]-4 '-O-methylnorlaudanosoline (0.18 %) is slightly better incorporated into reticuline than (R ,S)-[1-3H]-6-0-methylnorlaudanosoline (0.12 %) in feeding experiments to Litsea glutinosa [19] may be within experimental error, but demonstrates that the enzyme systems introducing the second 0-methyl-group are probably rather unspecific.…”

Section: Discussionsupporting

confidence: 87%

Partial Purification and Properties of S-Adenosylmethionine: (R), (S)-Norlaudanosoline-6-O-Methyltransferase from Argemone platyceras Cell Cultures

1983

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A new enzyme, S-adenosylmethionine: (R), (S)-norlaudanosoline-6-O-methyltransferase, was isolated from the soluble protein extract of A. PLATYCERAS cell cultures and purified approximately 80-fold. This enzyme catalyses the formation of 6-O-methylnorlaudanosoline, and, to a minor extent, 7-O-methylnorlaudanosoline from SAM and (S), as well as (R), norlaudanosoline. The apparent molcular weight of the enzyme is 47000 Dalton. The pH-optimum of the enzyme is 7.5, the temperature optimum, 35 degrees C. Apparent K (M) values for (S) and (R)-norlaudanosoline were 0.2 mM, and for SAM, 0.05 mM. The transferase shows high substrate specificity for tetrahydrobenzylisoquinoline alkaloids. Simple orthophenols, like phenylpropane derivatives, coumarins or flavonoids, are not accepted as substrates. The enzyme is widely distributed in benzylisoquinoline-containing plant cell cultures and is present in differentiated plants like PAPAVER SOMNIFERUM.

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Section: Discussionsupporting

confidence: 87%

Partial Purification and Properties of S-Adenosylmethionine: (R), (S)-Norlaudanosoline-6-O-Methyltransferase from Argemone platyceras Cell Cultures

1983

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“…10) or related phenylacetaldehydes. The suggestion by HAHN [6], proposed many years ago, that the carbon atom at position 1 of benzylisoquinoline alkaloids is biogenetically derived from an appropriate a-keto-acid via a Pictet-Spengler-ring closure reaction which has received much recent support, [7][8][9][10][11] is now ruled out in our opinion. (S)norlaudanosoline is the first intermediate in the benzylisoquinoline pathway.…”

Section: Discussionmentioning

confidence: 99%

“…1 (route II). The intermediary nature of norlaudanosoline-1-carboxylic acid was recently claimed to be supported by in vivo [7][8][9] and in vitro [10, 111 experiments. In order to distinguish between route I or II ( Fig. 1) it was clearly necessary to study the early steps of isoquinoline biosynthesis at the cell-free level.…”

Section: Introductionmentioning

confidence: 99%

Partial Purification and Properties of (S)-Norlaudanosoline Synthase fromEschscholtzia tenuifoliaCell Cultures

et al. 1983

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A new enzyme, (S)-norlaudanosoline synthase, which catalyses the synthesis of (S)-norlaudanosoline from dopamine and 3,4-dihydroxyphenylacetaldehyde was isolated from the soluble protein extract of ESCHSCHOLTZIA TENUIFOLIA cell suspension cultures and purified approximately 40-fold. The apparent molecular weight of the enzyme is 15 500 Dalton. The pH optimum is 7.8, temperature optimum 40 degrees C, apparent K (M) values for dopamine and dihydroxyphenyl-acetaldehyde are 1.5 mM and 0.7 mM respectively. The synthase shows high substrate specificity in that only the phenylacetaldehydes are transformed but not the phenylpyruvates. No apparent cofactor requirement could be demonstrated. By means of isoelectric focusing and disc-gel electrophoresis evidence was obtained for the existence of four norlaudanosoline synthase isoenzymes, none of which catalyses the reaction of dopamine with 3,4-dihydroxyphenylpyruvate. These enzymes are responsible for the synthesis of (S)-norlaudanosoline, the key intermediate in the formation of isoquinoline alkaloids occurring in the plant kingdom.

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“…A new lipid constituent methyl 11, 12, 15-trihydroxy-13 (14)-octadecenoate (86) was recently isolated from the leaves of A. annua [61]. A lipophilic fraction of A. annua was found to contain aurantiamide acetate, a dipeptide (87) [84] ( Figure 10).…”

Section: Miscellaneous Components and Natural Products From Endophytementioning

confidence: 99%

“…The structure elucidation including its relative and absolute configuration of compound 60 was not based on the real isolation from essential oil extract but was determined with the help of organic synthesis [60]. The new bisnor cadinane sesquiterpene 61 was lately isolated from A. annua [61]. In addition, two sesquiterpene plant hormones, abscisic acid (62), and its methyl ester (63) were found in an Indian growing A. annua [62] (Figure 7, Table 1).…”

Section: Terpenoids From a Annuamentioning

confidence: 99%

A golden phoenix arising from the herbal nest — A review and reflection on the study of antimalarial drug Qinghaosu

Liu

2010

Front. Chem. China

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Qinghaosu (QHS) and its derivatives are a new generation of antimalarial drugs characterized by fast action, high efficacy, and good tolerance. This feature article states the discovery of QHS from traditional Chinese medicine qinghao (Artemisia annua L.) and reviews the progress during the past four decades in the research of phytochemistry of A. annua, chemical reactions and biotransformation of QHS, chemical synthesis and biosynthesis of QHS, synthesis and antimalarial activity of QHS derivatives and analogs, pharmacological studies, clinical application, and the antimalarial mechanism. Undoubtedly, QHS is an example of the value of traditional Chinese medicine in modern medicinal research.

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The biosynthesis of reticuline

Cited by 13 publications

References 0 publications

Partial Purification and Properties of S-Adenosylmethionine: (R), (S)-Norlaudanosoline-6-O-Methyltransferase from Argemone platyceras Cell Cultures

Partial Purification and Properties of S-Adenosylmethionine: (R), (S)-Norlaudanosoline-6-O-Methyltransferase from Argemone platyceras Cell Cultures

Partial Purification and Properties of (S)-Norlaudanosoline Synthase fromEschscholtzia tenuifoliaCell Cultures

A golden phoenix arising from the herbal nest — A review and reflection on the study of antimalarial drug Qinghaosu

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