HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Wynn, J. P. Articles by Ratledge, C. Search for Related Content PubMed PubMed Citation Articles by Wynn, J. P. Articles by Ratledge, C. Agricola Articles by Wynn, J. P. Articles by Ratledge, C.

Biochemical events leading to the diversion of carbon into storage lipids in the oleaginous fungi Mucor circinelloides and Mortierella alpina

Centre for Advanced Lipid Research, Department of Biological Sciences, University of Hull, Hull HU6 7RX, UK¹
Department of Microbiology, Universitii Kebangsaan, Malaysia, 43600 Bangi, Salangor Darul Ehsan, Malaysia²

Author for correspondence: James P. Wynn. Tel: +44 1482 465507. Fax: +44 1482 465458. e-mail: j.p.wynn{at}biosci.hull.ac.uk

The biochemical events associated with the onset of lipid accumulation in Mucor circinelloides and Mortierella alpina, under conditions of nitrogen-limited growth, have been elucidated; they differ in key aspects from those described in oleaginous yeasts. The NAD⁺:isocitrate dehydrogenases of Mc. circinelloides and Mort. alpina were not absolutely dependent on AMP for activity. Furthermore, changes in the cellular adenine nucleotide pools and energy charge were different from those reported for oleaginous yeasts. In Mc. circinelloides ATP, ADP and AMP concentrations all decreased by 50% after nitrogen limitation, leading to a constant energy charge at the expense of the size of the total adenylate pool. Pyruvate carboxylase in Mc. circinelloides was cytosolic, having implications for the organization of lipid synthesis in filamentous fungi. As a result of the data obtained, a revised and more concerted mechanism for the initiation of storage lipid accumulation is put forward for filamentous fungi.

Keywords: AMP deaminase, NAD⁺:isocitrate dehydrogenase, lipid accumulation

Abbreviations: dO₂, dissolved oxygen concentration; NAD:ICDH, NAD⁺:isocitrate dehydrogenase; PFK, phosphofructokinase

This article has been cited by other articles:

				Y. Zhang, I. P. Adams, and C. Ratledge Malic enzyme: the controlling activity for lipid production? Overexpression of malic enzyme in Mucor circinelloides leads to a 2.5-fold increase in lipid accumulation Microbiology, July 1, 2007; 153(7): 2013 - 2025. [Abstract] [Full Text] [PDF]

				Y. Kamisaka, N. Noda, and M. Yamaoka Appearance of Smaller Lipid Bodies and Protein Kinase Activation in the Lipid Body Fraction Are Induced by an Increase in the Nitrogen Source in the Mortierella Fungus J. Biochem., February 1, 2004; 135(2): 269 - 276. [Abstract] [Full Text] [PDF]