Glycine crystal structure

Fig. 6. Backscattered Raman and ROA spectra of native (top pair) and A-state (second pair) bovine G -lactalbumin, and of native (third pair) and A-state (bottom pair) equine lysozyme, together with MOLSCRIPT diagrams of the crystal structures (PDB codes lhfz and 2eql) showing the tryptophans. The native proteins were in acetate buffer at pH 4.6 and 5.6, respectively, and the A-states in glycine buffer at pH 1.9. The native-state and A-state spectra were recorded at 20°C and 2°C, respectively.

Hardness data for only two amino acids were found in the literature. They are glycine and alanine. They are the smallest of the amino acids. Both consist of rather flat tablet-like collections of atoms that form layered crystal structures in which the molecular sub-groups within the layers are held together by hydrogen bonds (Albrecht and Corey, 1939), and the molecules by London forces. Their hardnesses are ... 

Fig. 14. Structural prediction and modeling of a fragment of FHA from B. pertussis containing Rl-repeats. (A) Successive stages in the modeling. From top to bottom identification of the consensus sequence repeat, generation of 2D template of the coil, and the modeled 3D structure. In the consensus sequence, letters indicate residues that are conserved at the level of >60% identity, x is any residue and filled circles represent bulky nonpolar residues. Apolar residues are in red glycine in green. In the 2D template, open circles denote any (but mainly polar) residues, while filled circles denote conserved, mainly nonpolar, residues. Circles inside the coil contour indicate side chains located inside the structure and circles outside the contour denote side chains facing the solvent. Arrows indicate /(-strands. (B) A fragment of the crystal structure of FHA (Clantin et al, 2004) (on the top, in green color) and the 3D model (bottom, in brown).

Fig. 36. Structure of a-glycine crystals. Projection along the c-axis. A and B are proposed sites for the Cu(II) impurities. (Adapted from Ref. 58)...

We shall illustrate the principle here using four examples of centrosymmetric crystals (/ ,S)-serine (45,78), W-acetylvaline, glycine (47), and glyclygly-cine (79). All four crystal structures appear in monoclinic symmetry (point symmetry Urn). 

The crystal structures of Ag(Gly)69 and Ag(HGly)NOs405 have been determined. For the latter compound, the silver ions bridged centrosymmetrically related carboxyl groups to form dimers of glycine. The actual composition was best represented as (NH3CH2C02 Ag+)2(NOi )2. Below —55 °C the compound was found to be ferroelectric. It was the first crystal containing either silver or the nitrate ion in which ferroelectridty was observed.406... 

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