NMR Studies of Erythrocyte Metabolism

Ethanol transport in Zymomonas mobilis measured by using in vivo nuclear magnetic resonance spin transfer

“…The conversion of glucose to ethanol was monitored by using 13 C NMR experimental procedures previously described (32), replacing [1-13 C]xylose with [1][2][3][4][5][6][7][8][9][10][11][12][13] C]glucose. All 13 C spectra were processed by using Gaussian time windowing for resolution enhancement (32).…”

“…Two experiments were done, on the basis of our previous results obtained with xylose (32) and other data (33). They were started by the addition of D- [1][2][3][4][5][6][7][8][9][10][11][12][13] C]glucose to the suspension of Z. mobilis (see Materials and Methods), and 13 C NMR spectra were acquired every 54 s. From the ethanol signal intensities, extracytoplasmic and cytoplasmic volumes (ethanol spaces) and specific cytoplasmic volumes were calculated as described above. From these figures, compartmental concentrations of ethanol and glucose and the specific cytoplasmic volume of Z. mobilis were obtained for each of the 25 datum points (Fig.…”

“…The difference from the average V in ethanol ( (3,20), it would correspond to 100 mg of protein per ml of cytoplasmic space. Calibrating protein concentration versus cell size as has been done with erythrocytes (18) might enable the monitoring of the true cytoplasmic volume in Z. mobilis as a function of time with NMR.…”

Stoichiometric Relationship between Na+ Ions Transported and Glucose Consumed in Human Erythrocytes: Bayesian Analysis of 23Na and 13C NMR Time Course Data

“…Through glycolysis, each glucose molecule phosphorylates a net of two ADP molecules into two ATP molecules (19,20). However, there is variable/adjustable (depending on metabolic conditions) breaking of this 2:1 stoichiometric relationship because some of the glucose-carbon flux occurs via the pentose phosphate pathway (PPP) that loses one carbon atom as CO 2 for each pass through the shunt, and via the Rapoport-Luebering shunt (RLS) that bypasses the ADP phosphorylating step at phosphoglycerate kinase (EC 2.7.2.3) (21,22). It has been shown in our own work (23) that under physiological conditions the flux through the RLS (2,3-bisphosphoglycerate turnover) is 19% of the main glycolytic flux, and that 10% of the carbon flux (glucose 6-phosphate turnover) is via the PPP.…”

Analytical Solutions and Simulations for Spin-Echo Measurements of Diffusion of Spins in a Sphere with Surface and Bulk Relaxation

“…The rate of translational diffusion good approximation (16,17). This leads to the ability to of a solute inside cells can directly influence its rate of develop tractable, but still complicated, analytical expresmetabolism, or the rate at which it can convey a chemical sions relating NMR signal intensity to various experimental signal (1). Thus, knowledge of the diffusion coefficients of parameters, and the intrinsic diffusion coefficient.…”