Crystal structure of Hyp-1, a St. John’s wort protein implicated in the biosynthesis of hypericin

Michalska, K.; Fernandes, Humberto; Sikorski, M.; Jaskólski, Mariusz

doi:10.1016/j.jsb.2009.10.008

Cited by 52 publications

(76 citation statements)

References 49 publications

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“…Another well-established fungal enzyme, TcmN aromatase/cyclase, which participates in the cyclization and structural diversification of aromatic polyketides, has also been shown to contain a PR10/Bet v1 fold (Ames et al, 2008). Generally, PR10 proteins are thought to participate in the defense of plants against microorganisms and fungi (Chadha and Das, 2006), although putative roles in plant metabolism have been proposed (Swoboda et al, 1996;Fujimoto et al, 1998;Bais et al, 2003;Michalska et al, 2010). A Bet v1 protein from white birch (Betula alba) was also reported to possess ribonuclease activity (Bufe et al, 1996), whereas others from plants such as Arabidopsis thaliana, pepper (Capsicum annuum), and tobacco (Nicotiana tabacum) have been characterized as homologs of opium poppy major latex proteins (MLPs; Osmark et al, 1998).…”

Section: Introductionmentioning

confidence: 99%

Norcoclaurine Synthase Is a Member of the Pathogenesis-Related 10/Bet v1 Protein Family

2010

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Norcoclaurine synthase (NCS) catalyzes the first committed step in the biosynthesis of benzylisoquinoline alkaloids (BIAs). NCS from Thalictrum flavum (Tf NCS), Papaver somniferum (Ps NCS1 and Ps NCS2), and Coptis japonica (Cj PR10A) share substantial identity with pathogen-related 10 (PR10) and Bet v1 proteins, whose functions are not well understood. A distinct enzyme (Cj NCS1) with similarity to 2-oxoglutarate-dependent dioxygenases was suggested as the bona fide NCS in C. japonica. Here, we validate the exclusive role of PR10/Bet v1-type NCS enzymes in BIA metabolism. Immunolocalization of Ps NCS2 revealed its cell type-specific occurrence in phloem sieve elements, which contain all other known BIA biosynthetic enzymes. In opium poppy, NCS transcripts and proteins were abundant in root and stem, but at low levels in leaf and carpel. Silencing of NCS in opium poppy profoundly reduced alkaloid levels compared with controls. Immunoprecipitation of NCS from total protein extracts of T. flavum cells resulted in a nearly complete attenuation of NCS activity. A Ps NCS2-green fluorescent protein fusion introduced by microprojectile bombardment into opium poppy cells initially localized to the endoplasmic reticulum but subsequently sorted to the vacuole. In our hands, Cj NCS1 did not catalyze the formation of (S)-norcoclaurine from dopamine and 4-hydroxyphenylacetaldehyde.

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Section: Introductionmentioning

confidence: 99%

Norcoclaurine Synthase Is a Member of the Pathogenesis-Related 10/Bet v1 Protein Family

2010

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“…The applicability of the protocol for immunoblotting analysis was demonstrated by detecting Hyp-1 in H. perforatum leaves at different stages of development. Hyp-1 is a phenolic coupling protein belonging to a pathogenesisrelated class 10 (PR-10) family [10,11]. Hyp-1 has been suggested to attend to the biosynthesis of hypericin in H. perforatum [10] but not studied so far at the protein level in H. perforatum tissues.…”

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confidence: 99%

Optimization of Protein Extraction from Hypericum perforatum Tissues and Immunoblotting Detection of Hyp-1 at Different Stages of Leaf Development

2010

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Sample preparation is crucial for obtaining high-quality proteins for the purpose of electrophoretic separation and further analysis from tissues that contain high levels of interfering compounds. Hypericum perforatum is a medicinal plant that contains high amounts of phenolic compounds, of which hypericins, hyperforins, and flavonoids contribute to the antidepressant activities of the plant. This study focuses on obtaining optimized amounts of high-quality proteins from H. perforatum, which are suitable for electrophoretic analyses. From the tested protein extraction solutions, sodium borate buffers at pH 9 and 10 gave the best protein yields from mature H. perforatum leaves. With these buffers, relatively high protein yields could also be obtained from roots, stems, and flower buds. The protein extracts of all organs were well resolved in SDS-PAGE after an efficient removal of non-protein contaminants with PVPP, phenol extraction, and methanolic ammonium acetate precipitation. The method was suitable for high-quality protein extraction also from other tested species of genus Hypericum. The applicability of the protocol for immunoblotting was demonstrated by detecting Hyp-1 in H. perforatum leaves at different stages of development. Hyp-1, which has been suggested to attend to the biosynthesis of hypericin, accumulated in high amounts in H. perforatum leaves at mature stage.

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“…Four NCS enzymes namely Tf NCS from Thalictrum flavum, Ps NCS1 and Ps NCS2 from Papaver somniferum, and Cj PR10A from Coptis japonica share substantial identity with PR10 and Bet v1 proteins [66]. Similarly, the phenolic oxidative coupling protein (Hyp-1) from Hypericum perforatum which catalyze the condensation of two emodine molecules to the bioactive naphtha dianthrone hypericin, shows approximately 40% sequence identity with classic PR-10 proteins [67][68][69].…”

Section: Pr-10 Proteins: An Overviewmentioning

confidence: 99%

The Pathogenesis Related Class 10 proteins in Plant Defense against Biotic and Abiotic Stresses

Jain¹

2015

APAR

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One of the most represented group of Pathogenesis Related (PR) genes are those of the PR-10 class. PR-10 proteins are members of multi genic family, and they often occur in clusters at specific loci following gene duplication and amplification events. To date, large number of PR-10 genes have been cloned and characterized in different species in response to abiotic and biotic stress. This review is focused on recent studies that have described the role, distribution and structure of PR-10 genes in plant genomes. Recent findings have provided insights into the functional roles of PR-10 proteins as ribonuclease, as cytokinin-specific binding proteins, a mammalian lipid transport and plant abscisic acid (ABA) receptor proteins, or as enzyme, (S)-norco claurine synthase. PR-10 proteins are differentially expressed in the presence of different signaling molecules, biotic stresses such as fungal, viral and bacterial pathogens and a number of abiotic stresses. The possibility to use this knowledge for genetic improvement of plant resistance to pathogens through classical breeding approach or transgenic technology is discussed.

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Crystal structure of Hyp-1, a St. John’s wort protein implicated in the biosynthesis of hypericin

Cited by 52 publications

References 49 publications

Norcoclaurine Synthase Is a Member of the Pathogenesis-Related 10/Bet v1 Protein Family

Norcoclaurine Synthase Is a Member of the Pathogenesis-Related 10/Bet v1 Protein Family

Optimization of Protein Extraction from Hypericum perforatum Tissues and Immunoblotting Detection of Hyp-1 at Different Stages of Leaf Development

The Pathogenesis Related Class 10 proteins in Plant Defense against Biotic and Abiotic Stresses

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