Glycolipids applications, hydrophobic balance rules them all Germán Günther S. Laboratorio de Cinética y Fotoquímica Departamento de Química Orgánica y Físico Química Facultad de Ciencias Químicas y Farmacéuticas. Universidad de Chile 1
Glycolipids applications, hydrophobic balance rules them all Susana Sánchez D. Catalina Sandoval A. Departamento de Polímeros Depto. de Qca. Org. y Fco. Qca. Facultad de Cs. Químicas. Facultad de Cs. Qcas. y Farm. Universidad de Concepción Universidad de Chile 2
Glycolipids: Biomolecules lipid chain (lipophilic) plus a monosaccharide/oligosaccharide (hydrophilic) The most common contain: galactose, mannose, fucose, glucose, glucosamine, galactosamine, or sialic acid as sugar CLAFQO 2017 3
Glycolipids: Involved in cell-cell interactions (signaling, recognition and adhesion) are modulated by sugar molecules located on the surface of cell as glycoconjugates. CLAFQO 2017 4
Families of Compounds Studied 1 Sucrose Esters (Monoacyl) 2 Lactose Derivatives 3 Mannose Derivatives galactose, mannose, fucose, glucose, glucosamine, galactosamine, or sialic acid as sugar CLAFQO 2017 5
1. Sucrose CLAFQO 2017 6
Sucrose esterification Position 1’-O Position 6-O Position 6’-O CLAFQO 2017 7
General estructure of 6-O sucrose esters H O RCOO H O O H O O H O O OH OH H O CLAFQO 2017 8
Sucrose derivatives Substituent name Molecule MOS MDS MLS MMS MPS CLAFQO 2017 9
1.1 Three Stage Model of Solubilization 0,05 0,00 ∆ GP sat -0,05 -0,10 GP I II III -0,15 -0,20 -0,25 0 2 4 6 8 10 12 [MMS] / [POPC] I Saturation II Solubilization III Mixed Micelles CLAFQO 2017 10
Laurdan GP on Cuvette CH 3 N Laurdan H 3 C CH 3 O 800000 − I I = blue red GP 700000 + I I blue red 600000 Intensidad / u.a. 500000 400000 I blue = 440nm 300000 I red = 490nm 200000 100000 0 350 400 450 500 550 600 Longitud de onda / nm CLAFQO 2017 11
GP on the two-channel microscope ch1 ch1 ch1 ch2 GP(1-2/1+2) Blue filter Red filter Corrected Emission Spectra of Laurdan in DMSO 70 3 140x10 60 120 50 100 Fluorescence (au) % Transmittance 40 80 30 60 GP histogram 20 40 10 20 0 350 400 450 500 550 600 Wavelength (nm) Measurement of Laurdan GP in the GUVs using Sim-FCS program CLAFQO 2017 12
1.1 Three Stage Model of Solubilization 0,05 0,00 ∆ GP sat -0,05 -0,10 GP I II III -0,15 -0,20 -0,25 0 2 4 6 8 10 12 [MMS] / [POPC] I Saturation II Solubilization III Mixed Micelles CLAFQO 2017 13
1.1 Three Stage Model of Solubilization 0,05 0,00 ∆ GP sat -0,05 -0,10 GP I -0,15 -0,20 -0,25 0 2 4 6 8 10 12 [MMS] / [POPC] CLAFQO 2017 14
Effect of methylene units on GP sat 0.6 0.4 0.2 GP sat 0.0 -0.2 -0.4 8 12 16 Methylene Units GP sat for DODAC SUV`s ( ○ ) and DPPC vesicles ( ● ) with the series of sucrose esters at 25 ̊ C CLAFQO 2017 15
1.2Sucrose ester Micelles CLAFQO 2017 17
1.2 Effect on the Palisade of Direct Mixed Micelles CLAFQO 2017 18
1.2 Effect on the Palisade of Direct Mixed Micelles CLAFQO 2017 19
Direct Mixed Micelles Sucrose k 0 k - k q χ Triton X-100 /10 6 seg -1 /10 6 seg -1 /10 6 seg -1 esters 1 4.26 3.32 6.42 0.8 3.92 9.55 7.59 0.6 3.97 7.77 2.32 MCS 0.5 3.95 7.43 4.29 0 3,57 - 1.11 0.8 4.51 2.60 6.37 0.6 4.43 2.35 6.34 MLS 0.5 4.45 1.91 6.29 0 4.09 0.44 7.10 0.8 4.14 3.94 7.75 0.6 4.36 7.67 12.8 MPS 0.5 4.22 9.41 15.3 0 4.05 - 3.71 Effect of sucrose esters in the quenching process of pyrene by dodecylpyridinium chloride (DPC) in pure and mixed Triton X-100 micelles. CLAFQO 2017 20
Direct Mixed Micelles The disturbing effect on the micelle core, consequence of the difference in size of both hydrophobic tails (Triton X-100 and SE), plays an important role, and the blocking effect can be overcame when the hydrophobic tails of SEs are too short or too long compared with Triton alkyl chain. CLAFQO 2017 21
2 Lactose Derivatives CLAFQO 2017 22
Lactose CLAFQO 2017 23
Lactose Reaction Anomeric Position CLAFQO 2017 24
Lactose Derivatives DOL DLL DPL CLAFQO 2017 25
Photoselection effect in Laurdan emission in GUVs From: Bagatolli, L. A. (2006). "To see or not to see: Lateral organization of biological membranes and fluorescence microscopy." Biochimica Et Biophysica Acta-Biomembranes 1758 (10): 1541-1556. CLAFQO 2017 26
Hydrophobic mismatch in the lipid matrix CLAFQO 2017 27
Hydrophobic mismatch heads DPPC:DPPE 3:7 L. A. Bagatolli and E. Gratton, Biophysical Journal 78: 290 (2000) CLAFQO 2017 28
Hydrophobic mismatch tails DLPC:DPLC 1:1 L. A. Bagatolli and E. Gratton, Biophysical Journal 78: 290 (2000) CLAFQO 2017 29
Hydrophobic mismatch L. A. Bagatolli and E. Gratton, Biophysical Journal 78: 290 (2000) CLAFQO 2017 30
GUVs POPC:DPL (36% POPC) GUVs 30 o C top top center Intensity GP Image GP Image CLAFQO 2017 31
3 Mannose Derivatives CLAFQO 2017 32
CLAFQO 2017 33
Mannose CLAFQO 2017 34
Mannose Reaction Anomeric Position CLAFQO 2017 35
Mannose Products DOM DLM DPM MOM MLM MPM CLAFQO 2017 36
Monoalkyl Mannose But longer ones ¡¡¡ CLAFQO 2017 37
Spontaneous Curvature CLAFQO 2017 38
Monoalkyl Mannose CLAFQO 2017 40
CLAFQO 2017 41
Agglutination CLAFQO 2017 42
Agglutination CLAFQO 2017 43
Interaction Affects Membrane CLAFQO 2017 44
And now, Mannose plus a probe CLAFQO 2017 46
We hope CLAFQO 2017 47
Acknowledments The authors thank Fondecyt-Chile 1120196 (G.G.) 1140454 (S.S) C. Sandoval-Altamirano thanks to Conicyt Beca Doctorado Nacional 21120554 And also Thank you CLAFQO 2017 48
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