Please show your work: Determine the number of ATP\'s derived from the complete
ID: 786580 • Letter: P
Question
Please show your work:
Determine the number of ATP's derived from the complete aerobic metabolism of palmitoleic acid to CO2 by each of the following pathways (show your reasoning): Beta oxidation and production of beta-hydroxybutyrate in liver mitochondria, transport of beta-hydroxybutyrate to muscle and oxidation in muscle mitochondria (Answer: 100.5) You may assume that the oxidation of each NADH in the ETS yields 2.5 ATP's and the oxidation of each reduced flavoprotein (E-FADH2) via ubiquinol (QH2) yields 1.5 ATP's. You should consider the reaction that converts acetoacetate to acetoacetyl-SCoA as costing one GTP (ATP). If the second pathway is used, what percent of the ATP content of the palmitoleic acid is delivered to the muscle tissue by ketone body production and transport? (Separate the total ATP yield in (a) into ATP's produced in liver and ATP's produced in muscle, and express each as a fraction of the total.) (Answer: 86%)Explanation / Answer
Palmitic acid was the main long chain fatty acids (LCFA) that accumulated onto the anaerobic sludge when oleic acid was fed to an EGSB reactor. The conversion between oleic and palmitic acid was linked to the biological activity. When palmitic acid was fed to an EGSB reactor it represented also the main LCFA that accumulated onto the sludge. The way of palmitic acid accumulation was different in the oleic and in the palmitic acid fed reactors. When oleic acid was fed, the biomass-associated LCFA (83% as palmitic acid) were mainly adsorbed and entrapped in the sludge that became "encapsulated" by an LCFA layer. However, when palmitic acid was fed, the biomass-associated LCFA (the totality as palmitic acid) was mainly precipitated in white spots like precipitates in between the sludge, which remained "non-encapsulated." The two sludges were compared in terms of the specific methanogenic activity (SMA) in the presence of acetate, propionate, butyrate, and H(2)CO(2), before and after the mineralization of similar amounts of biomass-associated LCFA (4.6 and 5.2 g COD-LCFA/g of volatile suspended solids (VSS), for the oleic and palmitic acid fed sludge, respectively). The "non-encapsulated," sludge exhibited a considerable initial methanogenic activity on all the tested substrates, with the single exception of butyrate. However, with the "encapsulated" sludge only methane production from ethanol and H(2)/CO(2) was detected, after a lag phase of about 50 h. After mineralization of the biomass-associated LCFA, both sludges exhibited activities of similar order of magnitude in the presence of the same individual substrates and significantly higher than before. The results evidenced that LCFA accumulation onto the sludge can create a physical barrier and hinder the transfer of substrates and products, inducing a delay on the initial methane production. Whatever the mechanism, metabolic or physical, that is behind this inhibition, it is reversible, being eliminated after the depletion of the biomass-associated LCFA.