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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4
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pubmed:dateCreated |
1992-11-4
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pubmed:abstractText |
Three new cyclic heptapeptide hepatotoxins, [D-Ser1,ADMAdda5]microcystin-LR (1), [D-Asp3,-ADMAdda5]microcystin-LHar (2), and [ADMAdda5,Mser7]microcystin-LR (3), were isolated from the cyanobacterium (blue-green alga) Nostoc sp. strain 152, together with four known microcystins, [ADMAdda5]microcystin-LR (4), [ADMAdda5]microcystin-LHar (5), [D-Asp3,-ADMAdda5]microcystin-LR (6), and [DMAdda5]microcystin-LR (7). The structures of new microcystins were assigned on the basis of high-resolution fast atom bombardment mass spectrometry (HR FABMS), collisionally induced tandem FABMS (FABMS/MS), amino acid analysis, and gas chromatography (GC) on a chiral capillary column. All three new toxins contained 9-acetoxy-3-amino-2,6,8-trimethyl-10-phenyldeca-4,6-dienoic acid (ADMAdda) instead of the corresponding 9-methoxyl derivative (Adda), while 7 contains the corresponding 9-hydroxy analog (DMAdda). Compound 1 is the first microcystin reported that contains D-serine (D-Ser) in lieu of the D-alanine (D-Ala) unit which was thought to be an invariable amino acid component of the microcystins. Compound 2 has L-homoarginine (Har) instead of L-arginine (L-Arg) in 6 and D-aspartic acid (D-Asp) instead of D-erythro-beta-methylaspartic acid (D-MeAsp) in 5. Compound 3, the N-methylserine (Mser) variant of the N-methyldehydroalanine unit in 4, would be a biosynthetic precursor of 4.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:issn |
0893-228X
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
5
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
464-9
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:1391612-Amino Acids,
pubmed-meshheading:1391612-Bacterial Toxins,
pubmed-meshheading:1391612-Chromatography, Gas,
pubmed-meshheading:1391612-Chromatography, High Pressure Liquid,
pubmed-meshheading:1391612-Chromatography, Thin Layer,
pubmed-meshheading:1391612-Cyanobacteria,
pubmed-meshheading:1391612-Hydrolysis,
pubmed-meshheading:1391612-Liver,
pubmed-meshheading:1391612-Microcystins,
pubmed-meshheading:1391612-Molecular Structure,
pubmed-meshheading:1391612-Molecular Weight,
pubmed-meshheading:1391612-Peptides, Cyclic,
pubmed-meshheading:1391612-Spectrometry, Mass, Fast Atom Bombardment
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pubmed:articleTitle |
Three new microcystins, cyclic heptapeptide hepatotoxins, from Nostoc sp. strain 152.
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pubmed:affiliation |
Department of Microbiology, University of Helsinki, Finland.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
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