Proline betaine

Nash, D., Paleg, L.G. Wiskich, J.T. (1982). The effect of proline, betaine and some other solutes on the heat stability of mitochondrial enzymes. Australian Journal of Plant Physiology, 9, 45-57. 

Rudolph, A.S., Crowe, J.H. Crowe, L.M. (1986). Effects of three stabilizing agents - proline, betaine and trehalose on membrane phospholipids. Archives of Biochemistry and Biophysics, 245, 134-43. 

Miller, J. W Kleven, D. T., Domin, B. A., and Fremau Jr., R. T. (1997) Cloned sodium-land chloride-) dependent high affinity transporters for GABA, glycine, proline, betaine, taurine, and creatine, in Neurotransmitter Transporters Structure, Function, and Regulation (Reith, M. E. A., ed.). Humana Press, Totowa, NJ, pp. 101-150. 

Haardt, M., Kempf, B., Faatz, E. and Bremer, E. (1995). The osmoprotectant proline betaine is a major substrate for the binding-protein-dependent transport system ProU of Escherichia coli K-12, Mol. Gen. Genet., 246, 783-786. 

Water Potential (-bars) Proline Betaine (mmoles/kg dry weight) Population Growth Rate (day )... 

Human urine Cardiovascular risk 4680 1H NMR Isoleucine Valine Methylguanidine Hippurate 2-Hydroxibutirate Succine Scyllo-inositol Trans-aconitate Proline betaine (21)... 

Bacteria glycine betaine, choline-O-sulfate, proline betaine, taurine betaine,... 

Ectoine Proline Cfioline Proline betaine Glycine betaine... 

ProU, the other major transporter in these two species of bacteria, also has broad substrate specificities, with glycine betaine and proline betaine accumulated with particular efficiency. ProU is rapidly up-regulated by more than 100-fold during salt stress, and elevated expression of proU persists throughout the period of osmotic stress (Kempf and Bremer, 1998). 

The DAT, NET, and SERT are members of the family of Na+, Cl -dependent substrate-specific neuronal membrane transporters, which includes transporters for GABA, glycine, taurine, proline, betaine, and creatine (4-8). The putative structure of these transporters consists of 12 transmembrane domains with both the N- and C-terminal domains located within the cytoplasm. The mechanism of the transporter-mediated uptake of monoamines is believed to involve an electrogenic transport of monoamines by sequential binding and cotransport of Na+ and Cl-ions (4-8). 

Heinzmann, S. S., I. J. Brown, Q. Chan, M. Bictash, M. E. Dumas, S. Kochhar, J. Stamler, E. Holmes, P. Elliott and J. K. Nicholson (2010). Metabolic profiling strategy for discovery of nutritional biomarkers proline betaine as a marker of citrus consumption. Am J Clin Nutr 92(2) 436 3. 

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