Proteins soluble

Dopamine D3 antagonist 16.3 Sybyl Biopol. + Loop search FlexX 990 ACD, MW filtered, random 10 19 70 (15) — [14] 

Farnesyl pyrophosphatase synthase inhibitor 63 Modeller Gold 1009 diverse, druglike 14 — 60(1) — [18] 

Photoactivated rhodopsin-G-protein interaction inhibitor — — Autodock 1990 NCI diverse 2 22.2 — ECso = 45 [iM [20] 

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Albumins. Soluble proteins both in water and in dilute aqueous salt solutions found in all living tissue. Typical albumins are ovalbumin from eggs and lactalbumin from milk. 

Protamines. Strongly basic, low mol. wt. proteins which contain high levels of arginine, but no sulphur-containing amino-acids. They are soluble proteins, associated with nucleic acids and are obtained in large quantity from fish spermatozoa. 

Rec tor. Receptors are membrane-bound or soluble proteins or protein complexes exerting a physiological effect after binding of an agonist. 

The quantity of water is two to three times the weight of the hides. The salt from the cure dissolves in the water and the reverse of the curing takes place. The water is drawn into the hides by osmotic forces. The concentration of the salt solution is about 3-5 g/lOO mL. At this concentration some of the soluble proteins disperse. The soak water removes the salt, some proteins, some loose fat, blood, dirt, and manure. 

Secondary Structure. The silkworm cocoon and spider dragline silks are characterized as an antiparaHel P-pleated sheet wherein the polymer chain axis is parallel to the fiber axis. Other silks are known to form a-hehcal (bees, wasps, ants) or cross- P-sheet (many insects) stmctures. The cross-P-sheets are characterized by a polymer chain axis perpendicular to the fiber axis and a higher serine content. Most silks assume a range of different secondary stmctures during processing from soluble protein in the glands to insoluble spun fibers. 

Alpha helices D and E from the L and M subunits (Figure 12.14) form the core of the membrane-spanning part of the complex. These four helices are tightly packed against each other in a way quite similar to the four-helix bundle motif in water-soluble proteins. Each of these four helices provides a histidine side chain as ligand to the Ee atom, which is located between the helices close to the cytoplasm. The role of the Ee atom is probably to... 

Naively, one might assume that it should be possible to scan the sequence and pick out regions with about 20 consecutive hydrophobic amino acids. However, no such regions occur in the reaction center proteins. Just as in soluble proteins there are hydrophobic side chains at the... 

Important novel information has thus been obtained for the specific biological function of those molecules, but disappointingly few general lessons have been learned that are relevant for other membrane-bound proteins with different biological functions. In that respect the situation is similar to the failure of the structure of myoglobin to provide general principles for the construction of soluble protein molecules as described in Chapter 2. 

Although the side chains of most nonpolar amino acids in soluble proteins are usually buried in the interior of the protein away from contact with the aqueous solvent, a portion of them is exposed at the protein s surface, giving... 

Good.sell, D. S., and OLson, A. J., 1993. Soluble protein.s Size, shape and function. Trends in Biochemical Sciences 18 65—68. 

Certain proteins are found to be covalently linked to lipid molecules. For many of these proteins, covalent attachment of lipid is required for association with a membrane. The lipid moieties can insert into the membrane bilayer, effectively anchoring their linked proteins to the membrane. Some proteins with covalently linked lipid normally behave as soluble proteins others are integral... 

FIGURE 9.31 The known proteoglycans include a variety of structures. The carbohydrate groups of proteoglycans are predominantly glycosaminoglycans O-linked to serine residues. Proteoglycans include both soluble proteins and integral transmembrane proteins. 

Squalene monooxygenase, an enzyme bound to the endoplasmic reticulum, converts squalene to squalene-2,3-epoxide (Figure 25.35). This reaction employs FAD and NADPH as coenzymes and requires Og as well as a cytosolic protein called soluble protein activator. A second ER membrane enzyme, 2,3-oxidosqualene lanosterol cyclase, catalyzes the second reaction, which involves a succession of 1,2 shifts of hydride ions and methyl groups. 

The conformation of bovine myelin basic protein (MBP) in AOT/isooctane/water reversed micellar systems was studied by Waks et al. 67). This MBP is an extrinsic water soluble protein which attains an extended conformation in aqueous solution 68 but is more density packed at the membrane surface. The solubilization of MBP in the AOT reversed micelles depends on the water/AOT-ratio w0 68). The maximum of solubilization was observed at a w0-value as low as 5.56. The same value was obtained for another major protein component of myelin, the Folch-Pi proteolipid 69). According to fluorescence emission spectra of MBP, accessibility of the single tryptophane residue seems to be decreased in AOT reversed micelles. From CD-spectra one can conclude that there is a higher conformational rigidity in reversed micelles and a more ordered aqueous environment. 

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