Carbohydrate metabolism in Acanthamoeba castellanii. 1. The activity of key enzymes and [¹⁴C]-glucose metabolism

Abstract

1973. Carbohydrate metabolism in Acanthamoeba castellanii. 1. The activity of key enzyrnes and ['4C]-glucose metabolism. Can. J. Microbiol. 19: 1131-1136.The specific activities of a number of the key enzyrnes involved in carbohydrate metabolism in Acantha1noeba castellanii (Neff clone 1-12) have been determined. The following Embden-Meyerhof and pentose phosphate pathway enzymes were present: glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, hexokinase, phosphofructokinase, hexose diphosphatase, aldolase, glyceraldehydephosphate dehydrogenase, pyruvate kinase, and pyruvate-phosphate dikinase. The following tricarboxylic acid cycle enzyrnes were also found: citrate synthase, aconitase, isocitrate dehydrogenase, succinate dehydrogenase, fumarate hydratase, and malate dehydrogenase. The degradation of glu~ose-U-'~C to 14C02 was examined. Aerobic 14C02 production from glu~ose-U-'~C was 3.4-fold greater than anaerobic production. The data provide further evidence that the Embden-Meyerhof, pentose phosphate, and tricarboxylic acid cycle pathways are probably functional in A. castellanii. PRESCOTT, L. M., H. E. HOYME, D. CROCKETT et E. HUI. 1973. Carbohydrate metabolism in Acanthamoeba castellatzii. 1. The activity of key enzyrnes and [14C]-glucose metabolism. Can. J. Microbiol.19: 1131-1136. Nous avons determine les activitks spkcifiques de plusieurs enzyrnes clees impliquies dans le metabolisme des carbohydrates chez Acanthatnoeba castellanii (Neff clone 1-12). Dans les chemins metaboliques d'Embden-Meyerhof et du phosphate pentose, les enzyrnes suivantes sont presentes: la dehydrogenase glucose-6-phosphate, la dehydrogenase 6-phosphogluconate, l'hexokinase, la phosphofructokinase, la diphosphatase hexose, l'aldolase, la dehydrogenase glyceraldehyde phosphate, la kinase pyruvate, et la dikinase pyruvate-phosphate. Dans le cycle de l'acide tricarboxylique, les enzyrnes suivantes sont aussi trouvees: la synthase citrate, l'aconitase, la dehydrogenase isocitrate, la dehydrogenase succinate, l'hydratase fumarate et la dehydrogenase malate. La degradation du g l~c o s e -U -~~C en 14C02 fut examinee. La production aerobique du 14C02 a partir du glucose-U-14C est 3.4 fois superieure que la production anaerobique. Les donnees fournissent d'autres evidences que les chemins metaboliques d'Embden-Meyerhof, du phosphate pentose et du cycle de l'acide tricarboxylique sont probablement fonctionnels chez A. castellanii.praduit par le journal]

Effect of Glucose on Glycine Requirement of Acanthamoeba castellanii*

“…Acanthamoeba has a functional Embden-Meyerhof pathway (16) and excess glucose could favor the formation of serine from the prevalent intracellular alanine pools. Since, however, Acanthamoeba also has a functional glyoxylate cycle which can be glucogenic (17), acetate as a carbon source in the growth medium should supply the same intermediates, albeit not necessarily at a rate consonant with demand.…”

Glucose metabolism in the pathogenic free‐living amoebae: Tempting targets for treatment development

“…The three pFLA PKs share ~50% sequence identity with Hs PK. Interestingly, in addition to Ac PK, A. castellanii also possess a pyruvate‐phosphate dikinase (PPDK), the enzyme that catalyzes the conversion of pyruvate to PEP that has been shown to act in the glycolytic or gluconeogenic pathway in some systems (Prescott et al., 1973).…”

‘Targeting the feast of a sleeping beast’: Nutrient and mineral dependencies of encysted Acanthamoeba castellanii

“…The molecular and cell biology of encystment in Acanthamoeba have been reviewed extensively (Lloyd, 2014). There is evidence of the existence of the Embden‐Meyerhof, pentose phosphate and tricarboxylic acid cycle pathways that are functional in Acanthamoeba castellanii (Prescott, Hoyme, Crockett, & Hui, 1973) that shows the dependency of this protist pathogen on glucose. Inhibition of signalling pathways that target ion channels, cell surface receptors and second messengers like Ca 2+ and calmodulin have shown to affect these metabolic processes in an encysted Acanthamoeba (Baig, Iqbal, & Khan, 2013).…”