Title: | Geotrichum candidum gene expression and metabolite accumulation inside the cells reflect the strain oxidative stress sensitivity and ability to produce flavour compounds |
Author(s): | Pracharova P; Lieben P; Pollet B; Beckerich JM; Bonnarme P; Landaud S; Swennen D; |
Address: | "UMR GMPA, AgroParisTech, INRA, Universite Paris-Saclay, 78850 Thiverval-Grignon, France" |
ISSN/ISBN: | 1567-1364 (Electronic) 1567-1356 (Print) 1567-1356 (Linking) |
Abstract: | "Geotrichum candidum is a fungus-like yeast widely used as a starter culture for cheese ripening for its proteolytic and lipolytic activities and its contribution to the cheese flavours. The sequenced strain G. candidum CLIB 918 was isolated from cheese Pont-L'Eveque. This strain's ability to produce volatile compounds was compared to the ability of a known strong sulphur compound producer G. candidum strain (Gc203). The aminotransferase-coding genes BAT2 and ARO8 were identified to be involved in methionine catabolism. The production of volatile compounds indicated that the sequenced strain was a moderate producer compared to the strong producer strain. The major volatile compounds were produced from sulphur amino acid, branched-chain amino acid and fatty acid metabolisms. Metabolite content of the cells showed that the ability of the strain to produce volatile compounds was inversely proportional to its ability to store amino acids inside the cells. Reduced glutathione, hypotaurine and taurine intracellular concentrations and volatile fatty aldehyde production indicated the role of oxidative stress sensitivity in flavour production. The increase in expression of several genes in a Reblochon-type cheese at the end of ripening confirmed that oxygen and iron were key factors regulating cheese flavour production" |
Keywords: | "Amino Acids/*metabolism Cheese/microbiology Flavoring Agents/*metabolism *Gene Expression Regulation, Fungal Geotrichum/*genetics/isolation & purification/*metabolism Metabolic Networks and Pathways/genetics *Oxidative Stress Volatile Organic Compounds/*m;" |
Notes: | "MedlinePracharova, P Lieben, P Pollet, B Beckerich, J M Bonnarme, P Landaud, S Swennen, D eng Research Support, Non-U.S. Gov't England 2018/10/09 FEMS Yeast Res. 2019 Jan 1; 19(1):foy111. doi: 10.1093/femsyr/foy111" |