| Full text | |
| Author(s): |
Muniz, Gabriel S. Vignoli
;
Souza, Mariana C.
;
Duarte, Evandro L.
;
Lamy, M. Teresa
Total Authors: 4
|
| Document type: | Journal article |
| Source: | BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES; v. 1863, n. 7, p. 16-pg., 2021-04-17. |
| Abstract | |
The present work compares the interaction of the antibiotic levofloxacin (LVX) with zwitterionic and anionic liposomes composed of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dipalmitoyl-sn-glycero-3phospho-(1'-rac-glycerol) (DPPG), respectively. By using differential scanning calorimetry (DSC), and with spin labels incorporated into liposomes at two different depths of the bilayers, we investigated the changes induced on the membrane by increasing concentrations of LVX. Further information was obtained using intrinsic LVX fluorescence. Under the conditions used here, all techniques evinced that LVX has little affinity for DPPC zwitterionic membrane. Opposite to that, LVX exhibits a considerable affinity for anionic bilayers, with membrane partition constants K-p = (3.3 +/- 0.5) x 10(2) and (4.5 +/- 0.3) x 10(2), for gel and fluid DPPG membranes, respectively. On binding to DPPG, LVX seems to give rise to the coexistence of LVX-rich and -poor domains on DPPG membranes, as detected by DSC. At the highest LVX concentration used (20 mol%), DSC trace shows an increase in the cooperativity of DPPG gel-fluid transition, also detected by spin labels as an increase in the bilayer packing. Moreover, LVX does not induce pore formation in either DPPG or POPG vesicles. Considering the possible relevance of LVX-membrane interaction for the biological and toxicological action of the antibiotic, the findings discussed here certainly contribute to a better understanding of its action, and the planning of new drugs. (AU) | |
| FAPESP's process: | 18/20162-9 - Investigating the Pathogenesis and Drug Resistance in Microorganisms - Characterization and Control of ATP-Binding Cassette Transporters |
| Grantee: | Andrea Balan Fernandes |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 17/25930-1 - Characterization of lipid dispersions of biological relevance: structures and interactions |
| Grantee: | Maria Teresa Moura Lamy |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 14/50983-3 - INCT 2014: complex fluids |
| Grantee: | Antonio Martins Figueiredo Neto |
| Support Opportunities: | Research Projects - Thematic Grants |