Low Oxygen Availability Increases Itaconate Production by Ustilago maydis

Biotechnology and Bioengineering, vol. 122, pp. 3007–3017

Abstract

Itaconic acid is a monomer for high performance polymers. While produced in industry with the filamentous fungi Aspergillus terreus, the production with the smut fungus Ustilago maydis was proposed recently. The strict aerobic process suffers from high power input via gassing and stirring. Here, we investigated in detail possible scenarios for the reduction of energy use during cultivation. In contrast to fermentations with other organic acids, in which even small oxygen concentrations in the medium hinders production, low oxygen availability correlated with increased itaconic acid titer and yield. This is somewhat surprising, as not only the sensitivity of itaconic acid producing U. maydis to oxygen deprivation was previously reported, but also the lower degree of reduction compared to glucose is not directly arguing for improved yield. Scale ups from 0.4 to 30 L using different criteria confirmed the positive impact of low availability of oxygen on itaconic acid production, suggesting a shift in metabolic pathways under restricted oxygen conditions. Oxygen limitation, encountered more likely in industrial fermenters, can be effectively used as a process control strategy to enhance itaconic acid production in U. maydis, offering a new approach for improving the efficiency of industrial-scale biotechnological production.

Authors 8

1. Wolfgang Laudensack

   University of Kaiserslautern · Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau

   Affiliation as printed

   Institute of Bioprocess Engineering University of Kaiserslautern‑Landau Kaiserslautern Germany

2. Felix Bartzack

   University of Kaiserslautern · Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau

   Affiliation as printed

   Institute of Bioprocess Engineering University of Kaiserslautern‑Landau Kaiserslautern Germany

3. Niklas Erdmann

   University of Kaiserslautern · Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau

   Affiliation as printed

   Institute of Bioprocess Engineering University of Kaiserslautern‑Landau Kaiserslautern Germany

4. Sonja Schönrock

   Karlsruhe Institute of Technology

   Affiliation as printed

   Karlsruhe Institute of Technology Institute of Process Engineering in Life Sciences Karlsruhe Germany

   Karlsruhe Institute of Technology, Institute of Process Engineering in Life Sciences, Karlsruhe, Germany

5. Emely Fuderer

   Karlsruhe Institute of Technology

   Affiliation as printed

   Karlsruhe Institute of Technology Institute of Process Engineering in Life Sciences Karlsruhe Germany

   Karlsruhe Institute of Technology, Institute of Process Engineering in Life Sciences, Karlsruhe, Germany

6. Dirk Holtmann

   Karlsruhe Institute of Technology

   Affiliation as printed

   Karlsruhe Institute of Technology Institute of Process Engineering in Life Sciences Karlsruhe Germany

   Karlsruhe Institute of Technology, Institute of Process Engineering in Life Sciences, Karlsruhe, Germany

7. Lars M. Blank Aachen ABBt – Aachen Biology and Biotechnology iAMB-Institute of Applied Microbiology

   RWTH Aachen University

   Affiliation as printed

   ABBt – Aachen Biology and Biotechnology, iAMB ‐ Institute of Applied Microbiology RWTH Aachen University Aachen Germany

8. Roland Ulber corresponding

   University of Kaiserslautern · Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau

   Affiliation as printed

   Institute of Bioprocess Engineering University of Kaiserslautern‑Landau Kaiserslautern Germany