Transient excretion of succinate from Trichoderma atroviride submerged mycelia reveals the complex movements and metabolism of carboxylates

• Published in: Antonie van Leeuwenhoek Vol. 100; no. 1; pp. 55 - 66
• Main Authors: Olejníková, Petra, Hudecová, Daniela, Burgstaller, Wolfgang, Kryštofová, Svetlana, Varečka, Ludovít
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-06-2011; Springer; Springer Nature B.V
• Subjects: Biochemistry; Biological and medical sciences; Biological Transport; Biomedical and Life Sciences; Biotechnology; Carboxylic acids; Carboxylic Acids - metabolism; Excretion; Fundamental and applied biological sciences. Psychology; Fungi; Life Sciences; Medical Microbiology; Metabolism; Microbiology; Miscellaneous; Mycelium - growth & development; Mycelium - metabolism; Mycology; Organic acids; Original Paper; Plant Sciences; Soil Science & Conservation; Succinic Acid - metabolism; Trichoderma - growth & development; Trichoderma - metabolism; Trichoderma atroviride; H; Trichoderma atroviride; Carboxylic acids uptake; Succinate; ATPase; Proton-motive force; Trichoderma; Enzyme; transporting ATP synthase; Metabolism; Uptake; Fungi; Hydrolases; Fungi Imperfecti
• ISSN: 0003-6072; 1572-9699
• DOI: 10.1007/s10482-011-9564-3

Submerged growth of
Trichoderma atroviride
CCM F 534 on glucose-containing medium was accompanied by the excretion of organic acids (succinate, citrate, alpha-ketoglutarate, fumarate, aconitate). The excretion of succinate was transient. After 48–72 h cultivation, millimolar amounts of succinate disappeared from the medium. We studied the mechanism of the removal of succinate from the medium and demonstrated the activation of the inward transport of succinate by submerged mycelia. This transport was carrier-mediated, had a low solute specificity, and was driven by proton-motive force. The last aspect was provided by the activation of the H
+
-ATPase, as documented by measurements of ATPase activity and expression of the
pma
gene. The disruption of the
pma
gene abolished the capacity of the mycelia to re-uptake succinate but not its production. Results show that excreted carboxylates could serve as alternative nutrients in the late phase(s) of submerged growth, explain why inward transport system(s) for carboxylates are induced, and indicate that the inward-directed transport could interfere with the production of carboxylic acids by fungi.