Glycolysis

About: Glycolysis is a research topic. Over the lifetime, 10593 publications have been published within this topic receiving 507460 citations. The topic is also known as: GO:0006096 & glycolysis.

Techniques to Monitor Glycolysis

Abstract: An increased flux through glycolysis supports the proliferation of cancer cells by providing additional energy in the form of ATP as well as glucose-derived metabolic intermediates for nucleotide, lipid, and protein biosynthesis. Thus, glycolysis and other metabolic pathways that control cell proliferation may represent valuable targets for therapeutic interventions and diagnostic procedures. In this context, the measurement of glucose uptake and lactate excretion by malignant cells may be useful to detect shifts in glucose catabolism, while determining the activity of rate-limiting glycolytic enzymes can provide insights into points of metabolic regulation. Moreover, metabolomic studies can be used to generate large, integrated datasets to track changes in carbon flux through glycolysis and its collateral anabolic pathways. As discussed here, these approaches can reveal and quantify the metabolic alterations that underlie malignant cell proliferation.

Studies on the mechanism of fructose-induced hyperuricemia in man

Abstract: The precise biochemical basis for many instances of hyperuricemia in man are not clearly understood. Elucidation of the mechanism by which certain normal intermediates and their structural analogs alter the serum uric acid may be useful in delineating potential pathophysiological alterations leading to hyperuricemia. The infusion of fructose in man precipitates a number of biochemical changes including hyperlacticacidemia, decrease in serum inorganic phosphate, and decrease in serum glucose. This results from the phosphorylation of fructose to fructose-1-P and the entrance of this compound into the glycolytic pathway. An increase in serum uric acid concentration following the infusion of fructose was initially reported by Perheentupa and Raivio in 1967., although this has remained a controversial observation.

Muscle Phosphofructokinase Deficiency

Abstract: The clinical hallmarks of muscle phosphorylase deficiency (McArdle's disease) are muscle cramps and exercise intolerance, contracture following ischemic work, and episodic myoglobinuria. We have encountered a patient with all these symptoms who proved to lack muscle phosphofructokinase (PFK) rather than phosphorylase. This paper describes the results of biochemical and immunological characterization of the metabolic abnormality. Phosphofructokinase deficiency was first described in a detailed biochemical study by Tarui et al, 1 the only previous report. Phosphofructokinase catalyzes the conversion of fructose-6-phosphate to fructose 1 , 6-diphosphate (Fig 1). This enzymatic step is one of the main rate-limiting steps of glycolysis, 2 and there is evidence that the regulation of glycolysis by aerobic metabolism (the Pasteur effect) is mediated by factors regulating the activity of PFK. 3-5 Since glycogen accumulates in excessive amounts in muscle, PFK deficiency can be regarded as a fourth type of muscle glycogenosis, along with deficiencies of phosphorylase, amylo-1, 6-glucosidase

Combined expression of glucokinase and invertase in potato tubers leads to a dramatic reduction in starch accumulation and a stimulation of glycolysis.

Abstract: Summary The original aim of this work was to increase starch accumulation in potato tubers by enhancing their capacity to metabolise sucrose. We previously reported that specific expression of a yeast invertase in the cytosol of tubers led to a 95% reduction in sucrose content, but that this was accompanied by a larger accumulation of glucose and a reduction in starch. In the present paper we introduced a bacterial glucokinase from Zymomonas mobilis into an invertase-expressing transgenic line, with the intention of bringing the glucose into metabolism. Transgenic lines were obtained with up to threefold more glucokinase activity than in the parent invertase line and which did not accumulate glucose. Unexpectedly, there was a further dramatic reduction in starch content, down to 35% of wild-type levels. Biochemical analysis of growing tuber tissue revealed large increases in the metabolic intermediates of glycolysis, organic acids and amino acids, two- to threefold increases in the maximum catalytic activities of key enzymes in the respiratory pathways, and three- to fivefold increases in carbon dioxide production. These changes occur in the lines expressing invertase, and are accentuated following introduction of the second transgene, glucokinase. We conclude that the expression of invertase in potato tubers leads to an increased flux through the glycolytic pathway at the expense of starch synthesis and that heterologous overexpression of glucokinase enhances this change in partitioning.