Surface properties of new virginiamycin M(1) derivatives.
Three kinds of derivatives of the M(1) factor of virginiamycin have been synthesised: esters with long chain fatty acids, oximes with modified polar amino acids and bis-derivatives with both the ester and oxime function. The study of the surface tension time dependence of M(1) and its derivatives has shown that it is necessary to enhance simultaneously the hydrophobicity and the hydrophilicity of M(1) to render M(1) surface-active. A structure/function relationship study of the surface-active bis-derivatives has shown that enhancing the hydrophobicity of the molecule led to slower adsorption kinetics, higher stability of the monolayers formed and a better capacity to penetrate a membrane model. The repulsive electrostatic forces due to the presence of charges on the amino acids linked to M(1) lead to higher surface tensions, a greater molecular area at the interface and lower penetration into a membrane model. This study has demonstrated that modifying systematically the hydrophobicity and hydrophilicity of a non surface-active molecule allows the production of surface-active derivatives.
Nott
Katherine
K
Unité de Chimie Générale et Organique, Faculté Universitaire des Sciences Agronomiques de Gembloux, Belgium. nott.k@fsagx.ac.be
Paquot
Michel
M
Dufour
Samuel
S
Eeman
Marc
M
Deleu
Magali
M
D000327:Adsorption; D000596:Amino Acids / Q000737:chemistry; D004952:Esters / Q000737:chemistry; D005227:Fatty Acids / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D010091:Oximes / Q000737:chemistry; D055672:Static Electricity; D025364:Streptogramin A / Q000031:analogs & derivatives*; D013329:Structure-Activity Relationship; D013499:Surface Properties; D013500:Surface Tension; D013501:Surface-Active Agents
D000596:Amino Acids; D004952:Esters; D005227:Fatty Acids; D010091:Oximes; D013501:Surface-Active Agents; D025364:Streptogramin A