Enzymatic synthesis, surface and lipid interaction properties of novel rhamnolipids

Amongst glycolipidid biosurfactants, rhamnolipids have drawn particular attention as they have several interesting biological properties such as antimicrobial, antiphytoviral, zoosporicidal and plant defense elicitor activities [1-3]. It is generally recognised that these activities must be linked to the interaction of these molecules with constituents of biological membranes [4] but the detailed mechanism is far from being fully understood.
The objective of this work is double. First, it aims to investigate a new strategy of synthesis for the production of novel rhamnolipids [5] that could exhibit properties as promising for industrial and environmental applications as their natural counterparts while avoiding the use of the pathogenic Pseudomonas aeruginosa for their production. Secondly, their basic surface properties (critical aggregation concentration, surface tension at CAC and interfacial behaviour of their monolayer) and their interaction with model membranes are investigated in relation with their structure in order to give insight about the mechanism of their biological actions.

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[3] Lang S. et al. Appl. Microbiol. Biotechn. 1999;51:22.
[4] Aranda F.J. et al. Langmuir. 2007;23:2700.
[5] Nott K. et al. Process Biochemistry, http://dx.doi.org/10.1016/j.procbio.2012.11.019