Interior chain lengths

From the mean, interior chain length of 3-4, and the above evidence, it follows that a number of interior chains must comprise only 1-2 residues. Evidence in favor of this hypothesis has been obtained, during studies of R-enzyme action on glycogen a-dextrins, which shows that a few a-dex-trins contain two branch points which are separated by only one D-glucose residue. 

Determination of Exterior and Interior Chain Lengths of Glycogens... 

Sample C.L. fi-Atnylolysis limit, % Exterior chain length Interior chain length References... 

The increased affinity of amylopectins for iodine is partly accounted for by the increase in exterior and interior chain-lengths. Other factors are probably involved as sweet corn polysaccharides (C. L. 12-13) bind more iodine than does glycogen, and glutinous rice-starch (C. L. 18 jS-amylo-lysis limit, 47 %) is stained red rather than purple with iodine. ... 

Average interior chain length - Depending on the source of the glycogen and the method used 2-5 (1-2)... 

The softening effect of silicones results from their lubrication behaviour that affects both the surface and the interior of the fibre. The behaviour of polysiloxanes of the 10.230 type can be varied by adjusting the average values of x and y and the range of chain lengths present. Further variations are possible by varying the R groups. In view of the technical and... 

Fig. 10.7 RNA synthesis in vesicles. Membrane permeability can be regulated by choosing the correct chain length of the fatty acids in the phospholipids. Short chains (a) make the bilayer so unstable that even large molecules such as proteases can enter the vesicle interior and damage the polymerase. Carbon chains which are too long (b) prevent the entry of substrate molecules such as ADR RNA polymerisation in the vesicle occurs only with C14 fatty acids (c)...

Some authors based their approach to selective binding of the more lipophilic a-amino acids in water on hydrophobic effects using water-soluble, cavity-containing cyclophanes for the inclusion of only the apolar tail under renouncement of any attractive interaction of the hosts with the zwitterionic head . Kaifer and coworkers made use of the strong affinity of Stoddart s cyclobis(paraquat-p-phenylene) tetracation 33 for electron-rich aromatic substrates to achieve exclusive binding of some aromatic a-amino acids (Trp, Tyr) in acidic aqueous solution [48]. Aoyama et al. reported on selectivities of the calix[4]pyrogallolarene 34 with respect to chain length and t-basicity of aliphatic and aromatic amino acids, respectively [49]. Cyclodextrins are likewise water-soluble and provide a lipophilic interior. Tabushi modified )S-cyclodextrin with a 1-pyrrolidinyl and a carboxyphenyl substituent to counterbalance the... 

Much of the early discussion of micelle structure centered around the problem of whether the hydrocarbon part should be considered as solid-like or liquid-like, the latter referring to conditions similar to those in liquid alkanes. Up to high alkyl chain lengths, the melting points of the alkanes lie below ambient temperature thus providing an indication that there is a liquid-like interior. However, the constraint offered by the micelle surface may, of course, substantially change the conditions. 

Fluorescence techniques have also been used to determine the localization of molecules in membranes. Using this technique, the localization of the linear dye molecule 3,3 -diethyloxadicarboxyamine iodide (DODCI) in lipid bilayer vesides was determined as a function of lipid chain length and unsaturation. It was found that the fraction of the dye in the interior region of the membrane was decreased as a function of chain length in the order C12 > C14 > C16 > C18. In unsaturated lipids it was Ci4 i > C14 0 > C16 1 > C16 0, which is in agreement with the general observation that the penetration of amphiphilic molecules into the interior of membranes increases with an increase in the fluidity of the membrane structure [59]. 

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