Title: Surface-Induced Coacervation Facilitates Localized Precipitation of Mineral Precursors from Dilute Solutions

Abstract

Many organisms orchestrate the controlled precipitation of minerals. This physiological process takes place at ambient conditions, using soluble ions as building blocks. A widespread strategy for such crystallization processes is using a multistep route, where the initial phase is metastable and gradually transforms into the mature mineral phase. Even though the maturation of these intermediate phases has been intensively studied, it remains unclear how the initial, far from equilibrium phase can form within the cellular context. A model system for controlled biomineralization is the production of coccoliths by marine microalgae. Coccoliths are calcium carbonate crystalline arrays that form within the intracellular environment, at very low calcium concentrations. Here, we used coccolith-derived and synthetic polymers to study, in vitro, the chemical interactions between calcium ions and organic macromolecules that precede coccolith formation. We used in situ analyses, including state-of-the-art cryo-electron tomography and liquid-cell atomic force microscopy, to study the interactions in bulk solution and on organic surfaces simultaneously. The results unveil a chemical process in which a functional surface induces the precipitation of a polymer–Ca dense phase, or a coacervate, at chemical conditions where precipitation in solution is kinetically inhibited. This strategy demonstrates how organisms can form dense Ca-rich phases frommore » the submillimolar concentration of calcium within organelles. This Ca-rich phase can then transform into a mineral precursor in a subsequent step, without posing challenges to cellular homeostasis.« less

Authors:

Krounbi, Leilah ^[1]; Hedderick, Konrad ^[2]; Eyal, Zohar  ^[1];

• Search DOE PAGES for author "Eyal, Zohar"
• Search DOE PAGES for ORCID "0000-0002-8966-0624"

Aram, Lior ^[1]; Shimoni, Eyal ^[3]; Estroff, Lara A.  ^[4];

• Search DOE PAGES for author "Estroff, Lara A."
• Search DOE PAGES for ORCID "0000-0002-7658-1265"

Gal, Assaf  ^[1]

• Search DOE PAGES for author "Gal, Assaf"
• Search DOE PAGES for ORCID "0000-0003-1488-1227"

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+ Show Author Affiliations

1. Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
2. Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
3. Department of Chemical Research Support, Weizmann Institute of Science, Rehovot 7610001, Israel
4. Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States, Kavli Institute for Nanoscale Science at Cornell, Cornell University, Ithaca, New York 14853, United States

Publication Date:

Fri May 07 00:00:00 EDT 2021

Research Org.:

Weizmann Institute of Science, Rehovot (Israel)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1782279

Alternate Identifier(s):

OSTI ID: 1784865

Grant/Contract Number:  

SC0010560

Resource Type:

Published Article

Journal Name:

Chemistry of Materials

Additional Journal Information:

Journal Name: Chemistry of Materials Journal Volume: 33 Journal Issue: 10; Journal ID: ISSN 0897-4756

Publisher:

American Chemical Society

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Polymer particles; Dynamic light scattering; Precipitation; Acid and base chemistry; Polymers