Glycine function

T. Ogawa, Macromol. 2003, 36(22), 8330-8335. Simpfified Synthesis of Amphiphilic SUox-anes with Methyl Gluconyl Glycinate Functionalities via Transacetalation . 

Saul et al. (1978) and Poljak et al. (1974) note the superimposability of the a-carbons of Phe-Gly-Gly-Gly residues 98-101 in VL and Trp-Gly-Gln-Gly in residues 103-106 in VH of Newm. They consider this as evidence against these glycines functioning as a pivot and attribute the invariance of the Gly residues to the need for VH-VL and intrasubunit contacts and the limited space available in this portion of the molecule. Whether these invariant Gly residues can serve as a pivot will ultimately be established by comparisons of the filled and empty sites when a ligand specific for the entire site is available. 

There is no evidence that GABA or glycine function as neuromuscular transmitters in parasitic flatworms (32). The absence of GABA is particularly surprising given its wide occurrence in both vertebrates and invertebrates. 

Polymer 13 by Incorporation of Glycine Functions in Cross-Linked Poly(acrylamide) (Section 5.1.1) [42]... 

NMD A receptors are selectively activated by A/-methyl-D-aspartate (NMD A) (182). NMD A receptor activation also requires glycine or other co-agonist occupation of an allosteric site. NMDAR-1, -2A, -2B, -2C, and -2D are the five NMD A receptor subunits known. Two forms of NMDAR-1 are generated by alternative splicing. NMDAR-1 proteins form homomeric ionotropic receptors in expression systems and may do so m situ in the CNS. Functional responses, however, are markedly augmented by co-expression of a NMDAR-2 and NMDAR-1 subunits. The kinetic and pharmacological properties of the NMD A receptor are influenced by the particular subunit composition. 

Glycine derivatives and aUphatic sulfonates are examples of compounds that can function in this way. The use of these inhibitors in cooling systems is usually lirnited by their biodegradabiUty and their toxicity toward fish. In addition, they can form thick, oily surface films, that may severely retard heat transfer. 

Therapeutic Function Antidote in heavy metal poisoning Chemical Name N-(2-Mercapto-1-oxopropyl)glycine Common Name Mercamidum... 

Relative concentrntions of different glycine species as a function of pH. Between about pH 3 and 9, the zwitterion is the principal species it has its maximum concentration at pH 6. the isoelectric point Below pH 2. the cation dominates above pH 10. the anion is the principal species. 

Introduction of an electron-withdrawing carboxy function at the x-carbon produces particularly reactive A-acyliminium ions, the so-called glycine cation equivalents, which are of great utility for the synthesis of x-amino acids. 

Glycine receptor function is modulated by alcohols and anesthetics [4]. Amino acid residue al(S267) is critical for alcohol potentiation, as mutation to small residues (Gly, Ala) enhance, and mutation to large residues (His, Cys, Tyr) diminish the ethanol effect. Glycine recqrtor modulation by Zn2+ involves structural determinants located within the large N-terminal domain. Additional glycinergic modulators include neuroactive steroids and the anthelmintic, ivermectin, which activates glycine receptors by a novel, strychnine-insensitive mechanism. 

Betz H, Laube B (2006) Glycine receptors recent insights into their structural organization and functional diversity. JNeurochem 97 1600-1610... 

The open channel has in most cases a selective permeability, allowing a restricted class of ions to flow,for example Na+, K+, Ca++ or Cl- and, accordingly, these channels are called Na+-channels, K+-channels, Ca -channels and Cr-channels. In contrast, cation-permeable channels with little selectivity reject all anions but discriminate little among small cations. Little is known about the structures and functions of these non-selective cation channels [1], and so far only one of them, the nicotinic acetylcholine receptor (nAChR, see Nicotinic Receptors), has been characterized in depth [2, 3]. The nAChR is a ligand-gated channel (see below) that does not select well among cations the channel is even permeable to choline, glycine ethylester and tris buffer cations. A number of other plasma... 

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