Glutamine characteristics

Ahmad, I., Larher, F., Mann, A.F., McNally, S.F. Stewart, G.R. (1982). Nitrogen metabolism of halophytes. IV. Characteristics of glutamine synthetase from Triglochin maritima L. New Phytologist, 91, 585-95. 

Solid state 13C CPMAS NMR spectra of Wheat High Molecular Weight (W.HMW) subunits show well resolved resonances identical with spectra of dry protein and peptide samples [24], Most of the amino acids side-chain resonances are found in the 0-35 ppm region followed by the alpha resonances of the most abundant amino acids glycine, glutamine and proline at chemical shifts of 42, 52 and 60 ppm, respectively, and the carbonyl carbons show a broad peak in 172-177 ppm region. The CPMAS spectra of hydrated whole HMW provides important information on the structural characteristics. 

Waagepetersen, H. S., Sonnewald, U., Larsson, O. M. etal. Multiple compartments with different metabolic characteristics are involved in biosynthesis of intracellular and released glutamine and citrate in astrocytes. Glia 35 246-252, 2001. 

Especially in the case of high-molecular-weight surface-active substances (such as proteins), the period of change may be sufficiently prolonged to allow easy observation. This arises because proteins are surface active. All proteins behave as surface-active substances because of the presence of hydrophilic-lipophilic properties imparted from the different polar, such as glutamine and lysine, and apolar, such as alanine, valine, phenylalanine, isovaline, amino acids. Proteins have been extensively investigated as regards their polar-apolar characteristics as determined from surface activity. 

The characteristic ratio of polylA -ro-hydroxyethyl-L-glutamine) in water at 303 K is found to be 10 1, in agreement with results obtained by Brant and Flory [J. Am. Chem. Soc. 1965, 87, 2791) for four other polypeptides with -CH2—R side chains. The circular dichroism of polylA -m-hydroxyethyl-L-glutamine) under these conditions, where the polypeptide is in a statistical conformation, exhibits a positive band at 216 nm. 

By pumping air through the reservoir, C02 is blown off and the pH of the medium will rise. However, if the air is pumped m too soon, the pH may rise too high this tends to occur with clones that utilize glutamine preferentially The input of air or C02 to adjust pH is learned by experience of the growth characteristics of the clone... 

Kurokawa H, Park YS, Iijima S, Kobayashi T (1994), Growth characteristics in fed-batch culture of hybridoma cells with control of glucose and glutamine concentrations, Biotechnol. Bioeng. 44 95-103. 

Consideration of other plasma amino acids also informs the diagnosis of inborn errors of urea synthesis. The plasma concentrations of glutamine and alanine are often elevated in parallel with or prior to the ammonium concentration as they act as a nitrogen buffer. Plasma arginine concentrations are low since the only synthetic route for arginine in humans is via the urea cycle. In contrast, the arginine concentration is elevated in ARG-1 deficiency. Hyperornithinemia and homocitrullinuria are the characteristic features of the hyperammonemia, hyperornithinemia, and homocitrullinuria (HHH) syndrome caused by a defect in the ornithine transporter (ORNT-1). 

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