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Biomineral shell formation under ocean acidification: a shift from order to chaos.

ABSTRACT: Biomineral production in marine organisms employs transient phases of amorphous calcium carbonate (ACC) in the construction of crystalline shells. Increasing seawater pCO2 leads to ocean acidification (OA) with a reduction in oceanic carbonate concentration which could have a negative impact on shell formation and therefore survival. We demonstrate significant changes in the hydrated and dehydrated forms of ACC in the aragonite and calcite layers of Mytilus edulis shells cultured under acidification conditions (1000 ?atm pCO2) compared to present day conditions (380 ?atm pCO2). In OA conditions, Mytilus edulis has more ACC at crystalisation sites. Here, we use the high-spatial resolution of synchrotron X-ray Photo Emission Electron Microscopy (XPEEM) combined with X-ray Absorption Spectroscopy (XAS) to investigate the influence of OA on the ACC formation in the shells of adult Mytilus edulis. Electron Backscatter Diffraction (EBSD) confirms that OA reduces crystallographic control of shell formation. The results demonstrate that OA induces more ACC formation and less crystallographic control in mussels suggesting that ACC is used as a repair mechanism to combat shell damage under OA. However, the resultant reduced crystallographic control in mussels raises concerns for shell protective function under predation and changing environments.

SUBMITTER: Fitzer SC

PROVIDER: S-EPMC4753494 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Biomineral shell formation under ocean acidification: a shift from order to chaos.

Fitzer Susan C SC Chung Peter P Maccherozzi Francesco F Dhesi Sarnjeet S SS Kamenos Nicholas A NA Phoenix Vernon R VR Cusack Maggie M

Scientific reports 20160215

Biomineral production in marine organisms employs transient phases of amorphous calcium carbonate (ACC) in the construction of crystalline shells. Increasing seawater pCO2 leads to ocean acidification (OA) with a reduction in oceanic carbonate concentration which could have a negative impact on shell formation and therefore survival. We demonstrate significant changes in the hydrated and dehydrated forms of ACC in the aragonite and calcite layers of Mytilus edulis shells cultured under acidifica ...[more]

PMID: 26876022

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Biomineral shell formation under ocean acidification: a shift from order to chaos.

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Biomineral shell formation under ocean acidification: a shift from order to chaos.

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