Strathprints Home | Open Access | Browse | Search | User area | Copyright | Help | Library Home | SUPrimo

The roles of the alternative NADH dehydrogenases during oxidative stress in cultures of the filamentous fungus Aspergillus niger

O'Donnell, Andrew and Harvey, Linda M. and Mcneil, Brian (2011) The roles of the alternative NADH dehydrogenases during oxidative stress in cultures of the filamentous fungus Aspergillus niger. Fungal biology, 115 (4-5). pp. 359-369. ISSN 1878-6146

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

Despite the importance of filamentous fungi in the biotechnology industry, little is known about their metabolism under the stressful conditions experienced in typical production fermenters. In the present study, oxygen enrichment was used to recreate an industrial batch process, and the effects of the increasing dissolved oxygen tension were studied as regards the cellular metabolism. It was found that elevated dissolved oxygen tension led to an oxidatively stressful environment, as detailed by rapid initial increases in reactive oxygen species (ROS) concentrations and antioxidant enzyme activities. Intracellular protein concentrations also decreased in oxygenated cultures; this appeared to be concomitant with a decrease in the adenosine-5'-triphosphate (ATP) pool in these cultures. Oxygenated cultures showed early senescence and death compared to aerated control cultures. Despite earlier studies proposing various mechanisms for such findings in fungal cultures subjected to oxidative stress, these findings can best be explained by the fact that in such cultures the activity of alternative NADH dehydrogenases was significantly increased, which served to maintain lower ROS concentrations throughout the duration of the process but in doing so also reduced the ability of the organism to create a proton motive force by which to drive ATP synthesis. The findings of the present study help further our understanding of the central roles of these highly conserved enzymes within fungal metabolism under oxidative stress.

Item type: Article
ID code: 33115
Notes: Copyright © 2011 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.
Keywords: adenosine triphosphate, aspergillus niger, biomass, cell culture techniques, fungal proteins, nadh dehydrogenase, oxidative stress, oxygen, reactive oxygen species, Therapeutics. Pharmacology, Infectious Diseases, Genetics, Ecology, Evolution, Behavior and Systematics, Plant Science
Subjects: Medicine > Therapeutics. Pharmacology
Department: Faculty of Science > Strathclyde Institute of Pharmacy and Biomedical Sciences
Related URLs:
    Depositing user: Pure Administrator
    Date Deposited: 05 Sep 2011 16:20
    Last modified: 25 Apr 2014 05:06
    URI: http://strathprints.strath.ac.uk/id/eprint/33115

    Actions (login required)

    View Item