Metabolic pathway
[4]: 73, 74 & 109 In contrast, glycolysis, pentose phosphate pathway, and fatty acid biosynthesis all occur in the cytosol of a cell.
The metabolism of a cell consists of an elaborate network of interconnected pathways that enable the synthesis and breakdown of molecules (anabolism and catabolism).
[4]: 91–93 The net reaction is, therefore, thermodynamically favorable, for it results in a lower free energy for the final products.
[10]: 578–579 A catabolic pathway is an exergonic system that produces chemical energy in the form of ATP, GTP, NADH, NADPH, FADH2, etc.
[11] An example of a coupled reaction is the phosphorylation of fructose-6-phosphate to form the intermediate fructose-1,6-bisphosphate by the enzyme phosphofructokinase accompanied by the hydrolysis of ATP in the pathway of glycolysis.
Additionally, most organisms can perform more efficient aerobic respiration through the citric acid cycle and oxidative phosphorylation.
Additionally plants, algae and cyanobacteria are able to use sunlight to anabolically synthesize compounds from non-living matter by photosynthesis.
The energy is utilized to conduct biosynthesis, facilitate movement, and regulate active transport inside of the cell.
The glyoxylate shunt pathway is an alternative to the tricarboxylic acid (TCA) cycle, for it redirects the pathway of TCA to prevent full oxidation of carbon compounds, and to preserve high energy carbon sources as future energy sources.
[16] The regulation methods are based on experiments involving 13C-labeling, which is then analyzed by nuclear magnetic resonance (NMR) or gas chromatography–mass spectrometry (GC–MS)–derived mass compositions.
The aforementioned techniques synthesize a statistical interpretation of mass distribution in proteinogenic amino acids to the catalytic activities of enzymes in a cell.
Within the mitochondrial metabolic network, for instance, there are various pathways that can be targeted by compounds to prevent cancer cell proliferation.
For instance, succinylacetone has been shown to decrease heme concentrations by inhibiting δ-aminolevulinic acid in murine erythroleukemia cells.
[20] The primary structure of heme-sequestering peptides, such as HSP1 and HSP2, can be modified to downregulate heme concentrations and reduce proliferation of non-small lung cancer cells.
Still, some of the adverse side effects in these patients included fatigue, nausea, diarrhea, decreased appetite, ascites, and anemia.
Side effects of enasidenib included nausea, diarrhea, elevated bilirubin and, most notably, differentiation syndrome.
[23] Glutaminase (GLS), the enzyme responsible for converting glutamine to glutamate via hydrolytic deamidation during the first reaction of glutaminolysis, can also be targeted.
The biosynthetic pathway to produce vinblastine, including 30 enzymatic steps, has been transferred into yeast cells which is a convenient system to grow in large amounts.
With these genetic modifications yeast can use its own metabolites geranyl pyrophosphate and tryptophan to produce the precursors of catharanthine and vindoline.
This process required 56 genetic edits, including expression of 34 heterologous genes from plants in yeast cells.
