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Scytonemides A and B, cyclic peptides with 20S proteasome inhibitory activity from the cultured cyanobacterium Scytonema hofmanii.

ABSTRACT: Two cyclic peptides, scytonemides A (1) and B (2), were isolated from the cultured fresh water cyanobacterium Scytonema hofmannii (UTEX 1834) by bioassay-guided fractionation using a proteasome inhibition assay. The planar structures of the compounds were determined by a combination of MS and 1D and 2D NMR spectroscopy. The advanced Marfey's method was used to determine the absolute configuration of both peptides. Scytonemide A possesses an unusual imino linkage, while scytonemide B is a depsipeptide containing 3-hydroxyoctanoic acid in the macrocycle. Both isolates were evaluated for their inhibition of the 20S proteasome, and scytonemide A displayed an IC(50) value of 96 nM, while scytonemide B was inactive at 50 ?M.

SUBMITTER: Krunic A

PROVIDER: S-EPMC3074188 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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Scytonemides A and B, cyclic peptides with 20S proteasome inhibitory activity from the cultured cyanobacterium Scytonema hofmanii.

Krunic Aleksej A Vallat Armelle A Mo Shunyan S Lantvit Daniel D DD Swanson Steven M SM Orjala Jimmy J

Journal of natural products 20101108 11

Two cyclic peptides, scytonemides A (1) and B (2), were isolated from the cultured fresh water cyanobacterium Scytonema hofmannii (UTEX 1834) by bioassay-guided fractionation using a proteasome inhibition assay. The planar structures of the compounds were determined by a combination of MS and 1D and 2D NMR spectroscopy. The advanced Marfey's method was used to determine the absolute configuration of both peptides. Scytonemide A possesses an unusual imino linkage, while scytonemide B is a depsipe ...[more]

PMID: 21058727

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