Specificity tertiary structural

DIMS9052 and DIMS9054 have similar primary and secondary structures, but nevertheless differ in their ability to form specific tertiary structures of parallel G4-tetramers (Fig. 3). This can be correlated to the difference in their IFN stimulatory capacity (Table 2) as well as in their ability to reduce the rate of disease progression in the EAE in vivo rat model (Fig. 4). 

Most nonfibrous proteins have a very precise and compact three-dimensional or tertiary structure formed when the a-helix and random coil of the polypeptide chain bends, twists, and folds over and back upon itself. The tertiary structure is stabilized by interactions of amino acid R-groups (Fig. 2-4a), and thus, is dictated by the primary structure. The biochemical function of a protein is intimately tied to its tertiary structure. That is, to function in a certain way, a protein must have the correct tertiary structure. Stated conversely only one specific tertiary structure will permit a protein to serve optimally a specific function (see also Figs. 4-3 and 4-4). 

Describe how disulfide bonds, hydrogen bonds, and salt bridges help hold protein molecules together in specific tertiary structures. 

In some cases, more is known about tertiary structure in RNA than in DNA. The full three-dimensional structure is known for some tRNA molecules from X-ray crystallography data. The structure involves several stem-loop regions of secondary structure which interact with one another to give a specific tertiary structure. The tRNA structure shown in Figure 2.8 includes stem-loop structures, unusual bases, pyrimidine-pyrimidine base pairs and... 

Does the considerable secondary structure retained by the molten globule represent part of the native structure, as it should if the molten globules were actually identical to the thermodynamically stable kinetic intermediates observed upon protein folding before organization of the specific tertiary structure [107,111,112,119,120] Hydrogen exchange and NMR studies of the structure of the supposedly... 

When heated over 50°C or subjected to strong acids or alkalis, proteins lose their specific tertiary structure and may form insoluble coagulates (e.g. egg white). This usually Inactivates their biological properties. 

Figure 4 summarizes these structures for the case of 3,5-disubstituted AB2 repeat units (its 3,4-disubstituted constitutional isomer, 3,4,5-trisubstituted AB3, and higher order AB4 and AB5 are not shown). These new libraries demonstrated that the primary structure rather than a small variation in the repeat unit is responsible for the tertiary structure therefore, an 85% predictability [80] for the primary structure that provides a specific tertiary structure was demonstrated. Once the... 

Zinc(II) seems to be used also to maintain certain specific (tertiary) structures of proteins. A number of proteins that contain Zn(ll) and that regulate the expression of DNA have been discovered in recent years. That is, this protein switches on and off the transcription of DNA, i.e., production of messenger RNA (see Chap. 4). Such a protein is called in general a transcription factor, whether it contains Zn(ll) or not. The transcription factors that contain Zn(ll) are called often zinc-finger protein, because the Zn(ll) here is used to maintain the specific structure of the protein (called finger ) so that it binds to a specific location of a DNA. 

Figure F.2d shows how several molecular subunits, each with a specific tertiary structure, aggregate together.

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