Correction to: Atomistic Simulations Modify Interpretation of Spin-Label Oximetry Data. Part 1: Intensified Water-Lipid Interfacial Resistances.

[This corrects the article PMC10249954.].

Atomistic simulations modify interpretation of spin-label oximetry data. Part 1: intensified water-lipid interfacial resistances.

The role of membrane cholesterol in cellular function and dysfunction has been the subject of much inquiry. A few studies have suggested that cholesterol may slow oxygen diffusive transport, altering membrane physical properties and reducing oxygen permeability. The primary experimental technique used in recent years to study membrane oxygen transport is saturation-recovery electron paramagnetic resonance (EPR) oximetry, using spin-label probes targeted to specific regions of a lipid bilayer.

Discerning Membrane Steady-State Oxygen Flux by Monte Carlo Markov Chain Modeling.

Molecular oxygen (O) permeability coefficients for lipid bilayers have previously been estimated using both electron paramagnetic resonance (EPR) oximetry and molecular dynamics simulation data. Yet, neither technique captures the fluxes that exist physiologically. Here, the dynamic steady state is modeled using a stochastic approach built on atomic resolution molecular dynamics simulation data.

Simulation Study of Breast Cancer Lipid Changes Affecting Membrane Oxygen Permeability: Effects of Chain Length and Cholesterol.

Tumor radiotherapy relies on intracellular oxygen (O) to generate reactive species that trigger cell death, yet hypoxia is common in cancers of the breast. De novo lipid synthesis in tumors supports cell proliferation but also may lead to unusually high levels of the 16:1 palmitoleoyl (Y) phospholipid tail, which is two carbons shorter than the 18:1 oleoyl (O) tail abundant in normal breast tissue. Here, we use atomic resolution molecular dynamics simulations to test two hypotheses: (1) the shorter, 16:1 Y, tail of the de novo lipid biosynthesis product 1-palmitoyl,2-palmitoleoyl-phosphatidylcholine (PYPC) promotes lower membrane permeability relative to the more common lipid 1-palmitoyl,2-oleoylphosphatidylcholine (POPC), by reducing oxygen solubility in the interleaflet region, and (2) cholesterol further lessens the permeability of PYPC by reducing overall O solubility and promoting PYPC tail order adjacent to the rigid cholesterol ring system.

Predicted Decrease in Membrane Oxygen Permeability with Addition of Cholesterol.

Aberrations in cholesterol homeostasis are associated with several diseases that can be linked to changes in cellular oxygen usage. Prior biological and physical studies have suggested that membrane cholesterol content can modulate oxygen delivery, but questions of magnitude and biological significance remain open for further investigation. Here, we use molecular dynamics simulations in a first step toward reexamining the rate impact of cholesterol on the permeation of oxygen through phospholipid bilayers.

Influence of Cholesterol on the Oxygen Permeability of Membranes: Insight from Atomistic Simulations.

Cholesterol is widely known to alter the physical properties and permeability of membranes. Several prior works have implicated cell membrane cholesterol as a barrier to tissue oxygenation, yet a good deal remains to be explained with regard to the mechanism and magnitude of the effect. We use molecular dynamics simulations to provide atomic-resolution insight into the influence of cholesterol on oxygen diffusion across and within the membrane.

Tricarbonyl(η5-formylcyclopentadienyl)manganese(I) and tricarbonyl(η5-formylcyclopentadienyl)rhenium(I) containing short π(CO)···π(CO) and π(CO)···π interactions.

The structures of tricarbonyl(formylcyclopentadienyl)manganese(I), [Mn(C(6)H(5)O)(CO)(3)], (I), and tricarbonyl(formylcyclopentadienyl)rhenium(I), [Re(C(6)H(5)O)(CO)(3)], (II), were determined at 100 K. Compounds (I) and (II) both possess a carbonyl group in a trans position relative to the substituted C atom of the cyclopentadienyl ring, while the other two carbonyl groups are in almost eclipsed positions relative to their attached C atoms. Analysis of the intermolecular contacts reveals that the molecules in both compounds form stacks due to short attractive π(CO).