## Abstract The interactions between chondroitin‐6‐sulfate (chondroitin sulfate C) and poly‐L‐lysine have been studied as models for investigation of possible complex formation between fibrous proteins and mucopolysaccharides. Results obtained using circular dichroism spectroscopy show that poly‐L‐
Interaction of sodium decyl sulfate with poly(L-ornithine) and poly(L-lysine) in aqueous solution
✍ Scribed by Iwao Satake; Jen Tsi Yang
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1976
- Tongue
- English
- Weight
- 574 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0006-3525
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✦ Synopsis
Abstract
The binding isotherms of sodium decyl sulfate to poly(L‐ornithine), poly(D,L‐ornithine), and poly(L‐lysine) at neutral pH were determined potentiometrically. The nature of a highly cooperative binding in all three cases suggests a micelle‐like clustering of the surfactant ions onto the polypeptide side groups. The hydrophobic interaction between the nonpolar groups overshadows the coulombic interaction between the charged groups. The titration curves can be interpreted well by the Zimm–Bragg theory. The average cluster size of bound surfactant ions is sufficiently large to promote the β‐structure of (L‐Lys)~n~ even at a very low binding ratio of surfactant to polypeptide residue, whereas the onset of the helical structure for (L‐Orn)~n~ begins after about 7 surfactant ions are bound to two turns of the helix. The CD results are consistent with this explanation.
📜 SIMILAR VOLUMES
## Abstract The interactions between chondroitin‐6‐sulfate and poly‐L‐arginine in aqueous salt solution have been investigated by circular dichroism techniques. In the presence of chondroitin‐6‐sulfate, at neutral pH, poly‐L‐arginine adopts the α‐helical conformation rather than “charged coil” form
## Abstract Poly(__N__^ε^‐acetoacetyl‐L‐lysine), poly(__N__^δ^‐acetoacetyl‐L‐ornithine) and poly(__N__^γ^‐acetoacetyl‐L‐diaminobutyric acid) form colored complexes with ferric ions in water/dioxane solutions. These complexes are soluble at pH values lower than 2.8 and show their maximum absorption
## Abstract Uncharged poly(__N__^ε^‐methyl‐L‐lysine) (PMLL) and its isomer, poly(__N__^δ^‐ethyl‐L‐ornithine) (PELO), in alkaline solution (pH ca. 12) undergo a helix‐to‐β transition upon mild heating at 50°C or higher in a manner similar to that of poly(L‐lysine) (PLL). The rate of conversion follo