Protein-like

Proteins, like other macromolecules, can be made into monolayers at the air-water interface either by spreading, adsorption, or specific binding. Proteins, while complex polymers, are interesting because of their inherent surface activity and amphiphilicity. There is an increasing body of literature on proteins at liquid interfaces, and here we only briefly discuss a few highlights. 

To introduce protein-like character tire interactions between beads (Arose separated by at least tliree bonds) that are nearest neighbours on a lattice are assumed to depend on tire nature of tire beads. The energy of a confomration. 

Protein-like stmctures are not only compact but also have low energy. With this in mind we have calculated the number of compact stmctures (CS) as CS with low energy for a given N. The number of CS in its most general fonn may be written as... 

Carbohydrates. The materials offered for fat replacement are either carbohydrate or protein and protein-like compounds (29). Table 3 fists carbohydrate fat-sparing agents. Another fisting is available (34) which includes materials offered on the European market. New compounds appear at such a rate that it is difficult to keep a current compilation proceedings from an aimual meeting are published (48). 

The rubber polyisoprene is a natural polymer. So, too, are cellulose and lignin, the main components of wood and straw, and so are proteins like wool or silk. We use cellulose in vast quantities as paper and (by treating it with nitric acid) we make celluloid and cellophane out of it. But the vast surplus of lignin left from wood processing, or available in straw, cannot be processed to give a useful polymer. If it could, it... 

Figure 17.16 Ribbon diagram representations of the structures of domain B1 from protein G (blue) and the dimer of Rop (red). The fold of B1 has been converted to an a-helical protein like Rop by changing 50% of its amino acids sequence. (Adapted from S. Dalai et al.,...

Enzymes are proteins of high molecular weight and possess exceptionally high catalytic properties. These are important to plant and animal life processes. An enzyme, E, is a protein or protein-like substance with catalytic properties. A substrate, S, is the substance that is chemically transformed at an accelerated rate because of the action of the enzyme on it. Most enzymes are normally named in terms of the reactions they catalyze. In practice, a suffice -ase is added to the substrate on which die enzyme acts. Eor example, die enzyme dial catalyzes die decomposition of urea is urease, the enzyme dial acts on uric acid is uricase, and die enzyme present in die micro-organism dial converts glucose to gluconolactone is glucose oxidase. The diree major types of enzyme reaction are ... 

Hyaluronic acid y binding domain (link-protein like)... 

As the ubiquitin proteasome pathway is a main route for protein clearance it is not surprising that in protein-opathies (disease caused by aggregate prone proteins) like sporadic Parkinson- or Huntington disease proteasome activity is reduced. Autosomal recessive loss of function of the E3 ligase parkin is the molecular base for one of the most common forms of familial Parkinson disease. 

In turn, 1O2 is a very electrophilic excited state species of molecular oxygen that interacts efficiently with electron-rich molecules, such as aminoadd residues of proteins like histidine, metionine, tryptophan, tyrosine, etc., by both physical and chemical quenching processes, eqns. 9 and 10 (Davies, 2003 Bisby et al., 1999). 

Sequence-specific heteropolymers, as a class of synthetic molecules, are unique in that they must be made by chemical steps that add one monomer unit at a time. Moreover, to create truly protein-like structures, which typically have chain lengths of at least 100 monomers and a diverse set of 20 side chains (or more), extremely efficient and rapid coupHngs under general reaction conditions are necessary. For these reasons, soHd-phase synthesis is typically used, so that excess reagents can be used to drive reactions to completion, and subsequent reaction work-ups are quite rapid. 

Dokholyan NV, Buldyrev SV, Stanley HE, Shakhnovich El. Discrete molecular dynamics studies of the folding of a protein-like model. Fold Des 1998 3 577-87. 

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