Naegleria gruberi metabolism

The completion of the genome project for Naegleria gruberi provides a unique insight into the metabolic capacities of an organism, for which there is an almost complete lack of experimental data. The metabolism of Naegleria seems to be extremely versatile, as can be expected for a free-living amoeboflagellate, but although considered to be fully aerobic, its genome also predicts important anaerobic traits. Other predictions are that carbohydrates are oxidised to carbon dioxide and water when oxygen is not limiting and that in the absence of oxygen the end-products will be succinate, acetate and minor quantities of ethanol and d-lactate. The hybrid mitochondrion/hydrogenosome has both cytochromes and an [Fe] hydrogenase, but seems to lack pyruvate-ferredoxin oxidoreductase. Genomic information also provides the possibility to identify drugs with a possible mode of action in the fatal primary amoebic meningoencephalitis caused by the closely related opportunistic pathogen Naegleria fowleri.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (85 K)Download as PowerPoint slideHighlights► The metabolic capacities of the amoeba Naegleria gruberi as deduced from its genome sequence are discussed. ► Carbohydrate, fatty acid, purine, pyrimidine and amino acid metabolism are all considered. ► Capacity to function both aerobically and in the absence of oxygen seems to be present. ► Some potential drug targets in the related human pathogen Naegleria fowleri are identified.