The shell matrix of the european thorny oyster, Spondylus gaederopus: microstructural and molecular characterization
peer-reviewed · Journal of Structural Biology · 2020
| Date | 2020-07-01 |
| Type | peer-reviewed |
| Venue | Journal of Structural Biology |
| Publisher | Elsevier BV |
| Contribution | downstream-application |
| DOI | 10.1016/j.jsb.2020.107497 |
| Citations (OpenAlex) | 20 |
Abstract
Molluscs, the largest marine phylum, display extraordinary shell diversity and sophisticated biomineral architectures. However, mineral-associated biomolecules involved in biomineralization are still poorly characterised. We report the first comprehensive structural and biomolecular study of Spondylus gaederopus, a pectinoid bivalve with a peculiar shell texture. Used since prehistoric times, this is the best-known shell of Europe’s cultural heritage. We find that Spondylus microstructure is very poor in mineral-bound organics, which are mostly intercrystalline and concentrated at the interface between structural layers. Using high-resolution liquid chromatography tandem mass spectrometry (LC-MS/MS) we characterized several shell protein fractions, isolated following different bleaching treatments. Several peptides were identified as well as six shell proteins, which display features and domains typically found in biomineralized tissues, including the prevalence of intrinsically disordered regions. It is very likely that these sequences only partially represent the full proteome of Spondylus, considering the lack of genomics data for this genus and the fact that most of the reconstructed peptides do not match with any known shell proteins, representing consequently lineage-specific sequences. This work sheds light onto the shell matrix involved in the biomineralization in spondylids. Our proteomics data suggest that Spondylus has evolved a shell-forming toolkit, distinct from that of other better studied pectinoids - fine-tuned to produce shell structures with high mechanical properties, while limited in organic content. This study therefore represents an important milestone for future studies on biomineralized skeletons and provides the first reference dataset for forthcoming molecular studies of Spondylus archaeological artifacts.
Methods and tools
- Spondylus gaederopus shell matrix proteomics: Microstructural and proteomic study of the European thorny oyster shell matrix. In the absence of genomic data, de novo reconstructed peptides were reported, most of them matching no known shell protein.
Methods it uses
- PEAKS: Commercial DP-based de novo
Data deposited
- Proteomic analysis of the shell organic matrix of Spondylus Gaederopus — as deposited · PXD016760