Chain-like molecular motifs

This structure can be described as the juxtaposition of chain-like molecular motifs. The emission spectrum of this compound contains four bands. The intensity of the hypersensitive D4 -> transition is close to six times that of the other transitions. These results, according... 

POLYMERS We investigate polymers—long chain-like molecules in which the motif of a small molecule is repeated many times over. We see how both molecular shape and interactions between polymer chains affect the physical properties of polymers. 

The tail domain in trichocyte Type I chains contains a tenfold P-C-X repeat, seven of them contiguously (Parry and North, 1998). Studies of its likely conformation suggest that it will most likely adopt a left-handed polyglycine II structure with three residues per turn (Fig. 3a). The cysteine residues would thus lie along one edge of the structure, where they would be in positions to form disulphide bonds with cysteine residues in a similar structure from a different molecule. The role of this sequence motif would appear to be that of stabilizing molecular assembly within the IFs. 

Thrombin is the pivotal trypsin-like protease for the regulation of thrombosis and hemostasis. Thrombin hydrolyzes its natural substrates by recognition of the Pro-Arg motif in the apolar S2- and the primary specificity SI pocket [42]. The molecular structure of the thrombin-CtA complex (Figure 1.11) showed that CtA was bound to the active site of the enzyme. The arginine side chain formed an electrostatic interaction with Aspl89, located at the bottom of the SI binding pocket. 

The thermodynamic driving force for amyloid formation is unquestionably the formation of aggregated p-strands that define complex P-sheet assemblies, involving two inter-molecular H-bonds per peptide residue plus additional side chain-side chain interactions that help stabilise and propagate strand aggregation. However, it seems likely that the folding pathway to amyloid could potentially be accessed by any protein stmctural motif as... 

The silks of insects like the silkworm Bombyx mori have been mentioned several times in this chapter in fact, far more is known about the biochemistry, molecular biology and genetics of the silkworm than of any spider. There are many similarities between insect silks and spider silks, e.g. the predominance of amino acids with short side chains or the occurrence of some sequence motifs, which can help to understand the general principles involved in the generation of their material properties. Yet, there are also major differences that have to be taken into account. Most insect silks are used as cocoons or protective webs in larval stages and originate in labial glands [32]. In contrast. 

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