Comparative proteomics of Rhizopus delemar ATCC 20344 unravels the role of amino acid catabolism in fumarate accumulation

PeerJ. 2017 Mar 30:5:e3133. doi: 10.7717/peerj.3133. eCollection 2017.

Abstract

The filamentous fungus Rhizopus delemar naturally accumulates relatively high amounts of fumarate. Although the culture conditions that increase fumarate yields are well established, the network underlying the accumulation of fumarate is not yet fully understood. We set out to increase the knowledge about fumarate accumulation in R. delemar. To this end, we combined a transcriptomics and proteomics approach to identify key metabolic pathways involved in fumarate production in R. delemar, and propose that a substantial part of the fumarate accumulated in R. delemar during nitrogen starvation results from the urea cycle due to amino acid catabolism.

Keywords: Amino acid metabolism; Fumarate; Nitrogen metabolism; Proteomics; Rhizopus delemar; Transcriptomics.

Grants and funding

This work has been carried out on a basis of a grant in the framework of the WUR IPOP Systems Biology program KB-17-003.02-026 “Genome-wide metabolic modelling and data integration of organic acid production in filamentous fungi” (DIO) and the BE-Basic (http://www.be-basic.org/) program F01.002 “Itaconic/fumaric acids: Novel economic and eco-efficient processes for the production of itaconic and fumaric acid” (JATR). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.