Biosynthesis of itaconic acid in Aspergillus terreus. II. Early stages in glucose dissimilation and the role of citrate.
نویسندگان
چکیده
We have shown that crude, cell-free extracts of Aspergillus terreus contain aconitase and cis-aconitic decarboxylase, and therefore quantitatively decarboxylate cis-aconitic, citric, and d-isocitric acids to itaconic acid and CO2 (1, 2). With use of labeled substrates, it has been shown that the isotope distributions in itaconic acid are consistent with the formation of cis-aconitic acid from citric acid and the subsequent decarboxylation of this compound (3). However, using whole cell preparations, Calam et al. (4), and more recently Eimhjellen and Larsen (5), were unable to demonstrate extensive conversion of citric to itaconic acid. It therefore seemed desirable to outline the intermediate stages between glucose uptake by A. terreus and itaconic acid synthesis and particularly to clarify the role of citric acid. Evidence has been obtained to indicate that in this organism glucose is dissimilated largely by the Embden-Meyerhof reactions and the tricarboxylic acid cycle. Citric acid is regarded as a precursor of itaconic acid; possible reasons why citric acid appears to be a poor precursor are discussed.
منابع مشابه
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عنوان ژورنال:
- The Journal of biological chemistry
دوره 226 2 شماره
صفحات -
تاریخ انتشار 1957