Glutamine transporter

SODIUM-DEPENDENT GLUTAMINE TRANSPORTERS IN PLASMA MEMBRANES MEDIATE THE TRANSFER OF GLUTAMINE FROM ASTROCYTES TO NEURONS 287... 

Glutamine, which has no net charge, is transported by a specific glutamine transporter. 

The mitochondrial translocators which have been most carefully assessed with respect to their role in control of metabolism are (1) the adenine nucleotide translocator with respect to its role in the control of respiration (2) the liver pyruvate transporter and the control of gluconeogenesis and (3) kidney glutamate and glutamine transport and their control of ammoniagenesis. 

In contrast to the studies of glutamine transport, several studies have suggested a potential role for the malate/a-ketoglutarate transporter in chronic acidosis [135,297]. Although Cheema-Dhadli and Halperin [135] were unable to demonstrate activation of the dicarboxylate (malate/phosphate) transporter in kidney cortex mitochondria from rats with chronic metabolic acidosis, Brosnan et al. [297] demonstrated that the malate/a-ketoglutarate carrier was activated in chronic acidosis. Additional studies are required to characterize this effect fully and to determine its role in the overall process of augmented ammonia formation in metabolic acidosis. However, it is... 

Na transport by the neural glutamine transporter ATAl. Pflugers Arch 443 92-101. (Provides an electrophysiological demonstration of electrogenic activity in the System A amino acid transporter)... 

Tamarappoo BK, Raizada MK, Kilberg MS (1997) Identification of a system N-like Na -dependent glutamine transport activity in rat brain neurons. J Neurochem 6S 954-960. 

Bode BP, Kaminski DL, Souba WW, Li AP. Glutamine transport in isolated human hepa-tocytes and transformed liver cells. Hepatology 21 511-520, 1995. 

Transport of glutamine into the mitochondria, important in kidney and intestine, has been a very controversial issue. At present, the mechanism of glutamine transport has not been solved [6]. 

Low SY, Taylor PM, Rennie MJ. Responses of glutamine transport in cultured rat skeletal muscle to osmotically induced changes in cell volume. J Physiol (Lond) 1996 492 877-885. 

A.1.3.25 Glutamine transporter, GlnQP. GlnPQ L lactis Fulyani et al. 2013... 

Poolman, B., Smid, E.J., and Konings, W.N. (1987) Kinetic properties of a phosphate-bond-driven glutamate-glutamine transport system in Streptococcus lactis and Streptococcus cremoris. J Bacteriol 169, 2755-2761. 

Fig. 9. Proposed model for the cellular compartmentalization of the reactions of nitrogen fixation, ammonium assimilation, purine synthesis, and ureide biogenesis in infected and uninfected cells of soybean root nodules. Uncertainty still exists with respect to the nature of the intermediate (e.g., IMP, XMP, xanthine, glutamine ) transported from the infected cell to the uninfected cell as well as the site of purine synthesis. In addition, as discussed in the text the site(s) of PRPP synthesis (plastid and/or cytosolic) and the path and site of synthesis (de novo from the PPP or via salvage) of tibose S-phosphate (R-S-P) are s not defined, lliese uncertainties are indicated with question marks and/or dashed lines. Lb, leghemoglobin.

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