Dataset Information

Interactions between Rhodamine Dyes and Model Membrane Systems-Insights from Molecular Dynamics Simulations.

ABSTRACT: rhodamines are dyes widely used as fluorescent tags in cell imaging, probing of mitochondrial membrane potential, and as P-glycoprotein model substrates. In all these applications, detailed understanding of the interaction between rhodamines and biomembranes is fundamental. we combined atomistic molecular dynamics (MD) simulations and fluorescence spectroscopy to characterize the interaction between rhodamines 123 and B (Rh123 and RhB, respectively) and POPC bilayers. while the xanthene moiety orients roughly parallel to the membrane plane in unrestrained MD simulations, variations on the relative position of the benzoic ring (below the xanthene for Rh123, above it for RhB) were observed, and related to the structure of the two dyes and their interactions with water and lipids. Subtle distinctions were found among different ionization forms of the probes. Experimentally, RhB displayed a lipid/water partition coefficient more than two orders of magnitude higher than Rh123, in agreement with free energy profiles obtained from umbrella sampling MD. this work provided detailed insights on the similarities and differences in the behavior of bilayer-inserted Rh123 and RhB, related to the structure of the probes. The much higher affinity of RhB for the membranes increases the local concentration and explains its higher apparent affinity for P-glycoprotein reconstituted in model membranes.

SUBMITTER: Magalhaes N

PROVIDER: S-EPMC8876248 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Interactions between Rhodamine Dyes and Model Membrane Systems-Insights from Molecular Dynamics Simulations.

Magalhães Nisa N Simões Guilherme M GM Ramos Cristiana C Samelo Jaime J Oliveira Alexandre C AC Filipe Hugo A L HAL Ramalho João P Prates JPP Moreno Maria João MJ Loura Luís M S LMS

Molecules (Basel, Switzerland) 20220219 4

<h4>Background</h4>rhodamines are dyes widely used as fluorescent tags in cell imaging, probing of mitochondrial membrane potential, and as P-glycoprotein model substrates. In all these applications, detailed understanding of the interaction between rhodamines and biomembranes is fundamental.<h4>Methods</h4>we combined atomistic molecular dynamics (MD) simulations and fluorescence spectroscopy to characterize the interaction between rhodamines 123 and B (Rh123 and RhB, respectively) and POPC bil ...[more]

PMID: 35209208

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Dataset Information

Interactions between Rhodamine Dyes and Model Membrane Systems-Insights from Molecular Dynamics Simulations.

Publications

Interactions between Rhodamine Dyes and Model Membrane Systems-Insights from Molecular Dynamics Simulations.

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