Membrane-Mediated Interactions between Nanoparticles on a Substrate

Investigations of the interactions between nanoparticles and lipid bilayer may yield insight into the understanding of the protein−biomembrane interactions and the cytotoxicity of drugs. Here, we theoretically investigate the membrane-mediated interactions between two nanoparticles supported on a substrate. We examine the effects of the packing density of lipids, the direct nanoparticle−lipid interaction, and the direct substrate−lipid interaction on the effective interactions between the nanoparticles and find the effective interactions between the two nanoparticles are mainly dominated by the competition of the deformations of the different parts of the lipid bilayers as well as the stretching of the lipid chains sandwiched between the nanoparticles. By varying the above-mentioned effects, the effective interactions between the two nanoparticles can be efficiently modulated. The results may provide some theoretical insight into experiments on the membrane-mediated nanoparticle organization on a substrate and organization of the membrane proteins or drug nanoparticles on the surfaces of the cellular membranes

Interactions between Band 3 Anion Exchanger and Lipid Nanodomains in Ternary Lipid Bilayers: Atomistic Simulations

Band 3 is an anion exchanger for chloride/bicarbonate in the plasma membrane of erythrocytes. The function of Band 3 may be influenced by the interactions between Band 3 and lipids or lipid domains in the plasma membrane. In this work, using atomistic molecular dynamics simulation, we investigate the interactions between Band 3 and nanosized lipid domains in ternary lipid bilayers composed of saturated lipids, unsaturated lipids, and cholesterol. The simulations show asymmetric interactions between Band 3 and lipid nanodomains in the two leaflets of a neutral lipid bilayer with lower cholesterol concentration. With an increase in cholesterol concentration in the bilayer, cholesterol affects the interactions between Band 3 and lipid domains by deforming the structure of the protein. Additionally, the anionic lipids, which prefer to bind to some specific sites of Band 3, also affect the interactions between Band 3 and lipid domains. This work provides some new insight into understanding the distribution of Band 3 in the plasma membrane of erythrocytes as well as its anion exchange function

Effects of Lid Domain Structural Changes on the Interactions between Peripheral Myelin Protein 2 and a Lipid Bilayer

Peripheral myelin protein 2 (P2) plays an important role in the stacking of the myelin membrane and lipid transport. Here we investigate the interactions between P2 and a model myelin membrane using molecular dynamics simulations, focusing on the effect of the L27D mutation and conformational changes in the α2-helix in the lid domain of P2. The L27D mutation weakens the binding of the lid domain of P2 on the membrane. The α2-helix is either folded or unfolded on the membrane. Compared with the α2-helix structure in water, the membrane stabilizes the structure of the α2-helix, whereas the unfolding of the α2-helix reduces the binding affinity of P2 on the membrane. These findings reveal the energetics of the mutant and the structural changes of P2 on the interactions between the protein and the lipid bilayer and help us to understand the microscopic mechanism of the formation of the myelin sheath structure and some neurological disorders

The relationship between overall N₂O emission and biochar addition under straw incorporation (S1) and removal (S0).

The relationship between overall N2O emission and biochar addition under straw incorporation (S1) and removal (S0).</p

Physicochemical properties of the surface soil and biochar.

Physicochemical properties of the surface soil and biochar.</p

Soil N₂O emissions from direct and indirect induced from NH₃ under different treatments.

Error bars denote standard errors. Definitions of C0, C1, C2 and C3 are given in caption of S1 Fig. (DOCX)</p

Comparison of path planning results by the conventional BAS algorithm on four different maps.

(a) Single regular obstacle. (b) Single irregular obstacle. (c) Multiple regular obstacles. (d) Multiple irregular obstacles.</p

S1 Graphical abstract -

Nitrous oxide (N2O) and ammonia (NH3) volatilization (AV) are the major pathways of nitrogen (N) loss in soil, and recently, N2O and NH3 mitigation has become urgently needed in agricultural systems worldwide. However, the influence of straw incorporation (SI) and biochar addition (BC) on N2O and NH3 emissions are still unclear. To fill this knowledge gap, a soil column experiment was conducted with two management strategies using straw ‐ straw incorporation (S1) and straw removal (S0) ‐ and four biochar application rates (0 (C0), 15 (C1), 30 (C2), and 45 t ha−1 (C3)) to evaluate the impacts of their interactions on N2O and NH3 emissions. The results showed that NO3−−N concentration and pH was the major contributors to affect the N2O and NH3 losses. Without biochar addition, N2O emissions was decreased by 59.6% (P2O mitigation when straw was removed, but increased N2O emission by 39.4%−83.8% when straw was incorporated. Additionally, biochar stimulated AV by 27.9%−60.4% under S0 and 78.6%−170.3% under S1. Consequently, SI was found to significantly interact with BC in terms of affecting N2O (P3 (P2O emissions and offset the mitigation potential by SI or BC alone. The indirect N2O emissions caused by AV, however, might offset the reduction of direct N2O caused by SI or BC, thus leading to an increase in overall N2O emission. This paper recommended that SI combined BC at the amount of 8.2 t ha−1 for maintaining a lower overall N2O emission for future agriculture practices, but the long-term impacts of straw incorporation and biochar addition on the trade-off between N2O and NH3 emissions and reactive N losses should be further examined and assessed.</div

S2 Fig -

The distribution of NH3 fluxes under (a) straw incorporation and (b) straw removal. Error bars denote standard errors. Definitions of C0, C1, C2 and C3 are given in caption of S1 Fig. (DOCX)</p

Soil NO₃⁻−N, NH₄⁺−N, total N, and organic matter content in different soil layers under different treatments.

Error bars denote standard errors. The different letters in the same soil layer indicate a significant difference (PFig 2.</p