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Simultaneous Counting of Molecules in the Halo and Dense-Core of Nanovesicles by Regulating Dynamics of Vesicle Opening.

ABSTRACT: We report the discovery that in the presence of chaotropic anions (SCN^- ) the opening of nanometer biological vesicles at an electrified interface often becomes a two-step process (around 30 % doublet peaks). We have then used this to independently count molecules in each subvesicular compartment, the halo and protein dense-core, and the fraction of catecholamine binding to the dense-core is 68 %. Moreover, we differentiated two distinct populations of large dense-core vesicles (LDCVs) and quantified their content, which might correspond to immature (43 %) and mature (30 %) LDCVs, to reveal differences in their biogenesis. We speculate this is caused by an increase in the electrostatic attraction between protonated catecholamine and the negatively charged dense-core following adsorption of SCN^- .

SUBMITTER: He X

PROVIDER: S-EPMC9306628 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Simultaneous Counting of Molecules in the Halo and Dense-Core of Nanovesicles by Regulating Dynamics of Vesicle Opening.

He Xiulan X Ewing Andrew G AG

Angewandte Chemie (International ed. in English) 20220218 15

We report the discovery that in the presence of chaotropic anions (SCN<sup>-</sup> ) the opening of nanometer biological vesicles at an electrified interface often becomes a two-step process (around 30 % doublet peaks). We have then used this to independently count molecules in each subvesicular compartment, the halo and protein dense-core, and the fraction of catecholamine binding to the dense-core is 68 %. Moreover, we differentiated two distinct populations of large dense-core vesicles (LDCVs ...[more]

PMID: 35129861

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