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| Section2 = }} Aspergillomarasmine A is an polyamino acid naturally produced by the mold ''Aspergillus versicolor''. The substance has been reported to inhibit two antibiotic resistance carbapenemase proteins in bacteria, New Delhi metallo-beta-lactamase 1 (NDM-1) and Verona integron-encoded metallo-beta-lactamase (VIM-2), and make those antibiotic-resistant bacteria susceptible to antibiotics. Aspergillomarasmine A is toxic to leaves of barley and other plants, being termed as "Toxin C" when produced by ''Pyrenophora teres''.〔 The molecule is a tetracarboxylic acid with four -COOH groups. One section of the molecule is the amino acid aspartic acid. This has two alanine molecules attached. Aspergillomarasmine B differs in that the last alanine is replaced by glycine. The name was given in 1965 by A. L. Haenni and colleagues, although the crystalline substance was first isolated in 1956 at the Société d’Etude et d’Applications Biologiques.〔 In addition to ''Aspergillus versicolor'', aspergillomarasmine A is also produced by the ascomycete ''Pyrenophora teres'' where it acts as a toxin in the barley net-spot blotch disease. In this organism the substance is produced using LL-''N''-(2-amino-2-carboxyethyl)-aspartic acid as an intermediate. Other producers of aspergillomarasmine A include ''Aspergillus flavus'',〔 ''Aspergillus oryzae'',〔 ''Colletotrichum gloeosporioides'', and ''Fusarium oxysporum''. In mice the LD50 toxic dose of aspergillomarasmine A is 159.8 mg/kg. ==Preparation== Aspergillomarasmine A can be made from a culture of molds that produce it. The liquid culture is filtered. Then from the filtrate, a precipitate is formed using calcium chloride, tricalcium phosphate and acetone. From the precipitate, the substance is redissolved at pH 9 in water. Then chromatographic separation in Amberlite IRC 50 with ammonia in water, and finally crystallisation at pH 3.0. At pH 2.5 aspergillomarasmine B crystallises. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Aspergillomarasmine A」の詳細全文を読む スポンサード リンク
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