Structural Changes of Alpha 1-Antitrypsin under Osmotic Pressure and in the Presence of Lipid Membranes

poster abstractAlpha 1-Antitrypsin (A1AT) is a glycoprotein that has been shown to have protective roles of lung cells against emphysema, a disease characterized by lung tissue destruction. Most known glycoproteins have been shown to play a role in cellular interactions but the exact role of the glycan chains is still under investigation. Previous electrophysiological measurements show that A1AT has a strong affinity to lipid bilayers perturbing the function of ion channels present in the membrane. We have performed contrastmatching small-angle neutron scattering (SANS) experiments to study the conformational changes of the glycosylated form of A1AT for different concentrations of the osmolyte poly(ethelene glycol) (PEG) and in the presence of two different lipid membranes: POPC and POPS. We also monitor the structural changes of the lipid vesicles in the presence of A1AT by SANS. Guinier fits were used as a first approximation to obtain the radius of gyration (Rg) of A1AT. Bragg peaks were used to study structural changes of lipid vesicles. We observed that the Rg of A1AT changes as a function of PEG concentration in solution and when in the presence of lipid vesicles. The deformations monitored through changes in A1AT’s Rg in the presence of lipid vesicles are compared to the deformations of the glycoprotein observed under osmotic pressure and to the structural changes observed in the lipid vesicles

The Total Syntheses of JBIR-94 and Two Synthetic Analogs and Their Cytotoxicities Against A549 (CCL-185) Human Small Lung Cancer Cells

We here disclose the total syntheses of the natural polyphenol JBIR-94 and two nonnatural analogs, whose structures are of interest for their bioactivity potential as radical scavengers. Although we initially attempted this by dually acylating both of putrecine’s amine nitrogens in a single pot, our endeavors with this method (which has been successfully reported by other groups) proved ineffectual. We accordingly opted for the lengthier approach of acylating each amine individually, which gratuitously prevailed and also aligns with separate literature precedent. Moreover, we here share our analysis of these target compounds’ cytotoxicities and IC50 values against A549 (CCL-185) human small lung cancer cells

The Total Syntheses of JBIR-94 and Two Synthetic Analogs and Their Cytotoxicities Against A549 (CCL-185) Human Small Lung Cancer Cells

We here disclose the total syntheses of the natural polyphenol JBIR-94 and two nonnatural analogs, whose structures are of interest for their bioactivity potential as radical scavengers. Although we initially attempted this by dually acylating both of putrecine’s amine nitrogens in a single pot, our endeavors with this method (which has been successfully reported by other groups) proved ineffectual. We accordingly opted for the lengthier approach of acylating each amine individually, which gratuitously prevailed and also aligns with separate literature precedent. Moreover, we here share our analysis of these target compounds’ cytotoxicities and IC50 values against A549 (CCL-185) human small lung cancer cells

Structural Changes of Alpha 1-Antitrypsin under Osmotic Pressure and in the Presence of Lipid Membranes

poster abstractAlpha 1-Antitrypsin (A1AT) is a glycoprotein that has been shown to have protective roles of lung cells against emphysema, a disease characterized by lung tissue destruction. Most known glycoproteins have been shown to play a role in cellular interactions but the exact role of the glycan chains is still under investigation. Previous electrophysiological measurements show that A1AT has a strong affinity to lipid bilayers perturbing the function of ion channels present in the membrane. We have performed contrastmatching small-angle neutron scattering (SANS) experiments to study the conformational changes of the glycosylated form of A1AT for different concentrations of the osmolyte poly(ethelene glycol) (PEG) and in the presence of two different lipid membranes: POPC and POPS. We also monitor the structural changes of the lipid vesicles in the presence of A1AT by SANS. Guinier fits were used as a first approximation to obtain the radius of gyration (Rg) of A1AT. Bragg peaks were used to study structural changes of lipid vesicles. We observed that the Rg of A1AT changes as a function of PEG concentration in solution and when in the presence of lipid vesicles. The deformations monitored through changes in A1AT’s Rg in the presence of lipid vesicles are compared to the deformations of the glycoprotein observed under osmotic pressure and to the structural changes observed in the lipid vesicles