tailieunhanh - Báo cáo khoa học: Biophysical characterization of synthetic rhamnolipids

Synthetic rhamnolipids, derived from a natural diacylated glycolipid, RL-2,214, produced by Burkholderia(Pseudomonas) plantarii, were analyzed biophysically. Changes in the chemical structures comprised variations in the length, the stereochemistry and numbers of the lipid chains, numbers of rhamnoses, and the occurrence of charged or neutral groups. | ỊFEBS Journal Biophysical characterization of synthetic rhamnolipids Jorg Howe1 Jorg Bauer2 Jorg Andra1 Andra B. Schromm1 Martin Ernst1 Manfred Rossle3 Ulrich Zahringer1 Jorg Rademann3 and Klaus Brandenburg1 1 Forschungszentrum Borstel Leibniz-Zentrum fur Medizin und Biowissenschaften Borstel Germany 2 Leibniz-Institut fur Molekulare Pharmakologie Berlin and Institut fur Chemie und Biochemie Freie Universitat Berlin Germany 3 European Molecular Biology Laboratory Outstation Hamburg EMBL c o DESY Hamburg Germany Keywords cytokine induction endotoxins organic synthesis rhamnolipids X-ray diffraction Correspondence K. Brandenburg Forschungszentrum Borstel Leibniz-Zentrum fur Medizin und Biowissenschaften Parkallee 10 D-23845 Borstel Germany Fax 49 4537188 632 Tel 49 4537 188 235 E-mail kbranden@ Received 27 June 2006 revised 24 August 2006 accepted 20 September 2006 doi Synthetic rhamnolipids derived from a natural diacylated glycolipid RL-2 214 produced by Burkholderia Pseudomonas plantarii were analyzed biophysically. Changes in the chemical structures comprised variations in the length the stereochemistry and numbers of the lipid chains numbers of rhamnoses and the occurrence of charged or neutral groups. As relevant biophysical parameters the gel b to liquid crystalline a phase behavior of the acyl chains of the rhamnoses their three-dimensional supramolecular aggregate structure and the ability of the compounds to intercalate into phospholipid liposomes in the absence and presence of lipopolysaccharide-binding protein were monitored. Their biological activities were examined as the ability to induce cytokines in human mononuclear cells and to induce chemiluminescence in monocytes. Depending on the particular chemical structures the physicochemical parameters as well as the biological test systems show large variations. This relates to the acyl chain fluidity aggregate structure and intercalation ability as well as the