Browsing by Author "Sanchez Arias, Kevin"
Now showing 1 - 1 of 1
Results Per Page
Sort Options
Item Estudio de las interacciones del péptido Alyteserin 1C y de su análogo catiónico con modelos de membranas(Universidad Santiago de Cali, 2020) Sanchez Arias, Kevin; Oñate Garzón, José Fernando; Polo Cerón, DorianAntimicrobial peptides are part of the innate immunity of most living things and have antimicrobial activity against bacterium, viruses, fungi and parasites. Their cationic characteristics make them selective towards bacterial membranes with anionic surfaces. In this study, the interaction of Alyteserin 1C peptides with a net charge of +2 and their net charge analogue +5 was evaluated on synthetic membrane models that simulate the membrane surface of Gram-negative bacterium and human erythrocytes. Using differential scanning calorimetry (DSC), the effect of the peptides on the thermotropic behavior of the membranes was determined. On the other hand, attenuated total reflection (Fourier transform infrared spectroscopy) (ATR-FTIR) was used to analyze the displacement of the vibrations of the carbonyl, methylene and phosphate groups of the phospholipids, as a consequence of the interaction with the peptide. Furthermore, the amide I band of the peptide was also analyzed before and after interacting with the membrane models to determine its secondary structure. The DSC results showed a decrease in the enthalpy (ΔH) and melting point (ΔTm) of the membrane models in the presence of both peptides. On the other hand, the vibrational frequency of the functional groups of the phospholipids increased in the presence of the peptides. Regarding the secondary structure, the +2 peptide exhibited a form of transition of β sheets / turns to structures of β sheets / α helix after binding with membrane models, while the +5 peptide had a transition of aggregation structures / not ordered to β-sheet structures / α helix after PC membrane binding and to non-ordered β sheet structures after PC / PG membrane binding.