An acidic protein, Hf15, from Haliotis fulgens involved in biomineralization

• Published in: Comparative biochemistry and physiology. Part A, Molecular & integrative physiology Molecular & integrative physiology, 2022-10, Vol.272, p.111276-111276, Article 111276
• Main Authors: Rivera-Pérez, Crisalejandra, Arroyo-Loranca, Raquel G., Hernández-Saavedra, Norma Yolanda
• Format: Article
• Language: English
• Subjects: Biomineralization; Crystallization; Decalcification; Gastropods; Shell matrix proteins
• ISSN: 1095-6433; 1531-4332
• DOI: 10.1016/j.cbpa.2022.111276

Biomineralization leads to the hardening of mineralized materials, such as the shell of Mollusk, to fulfill a wide range of functions, such as (but not limited to) skeletal support, protection of the soft tissues, navigation, etc. The study of the proteins responsible for this process, shell matrix proteins (SMPs), allows addressing questions related to structure-function relationship and to the mechanism of mineral formation, which is limited in gastropod species. In this study, a low molecular weight protein was isolated from the insoluble fraction after decalcification with acetic acid of the shell of Haliotis fulgens and, named Hf15. The unglycosylated protein has a theoretical molecular weight of 15 kDa, it possesses calcium and chiting binding properties. Hf15 can precipitate calcium carbonate in vitro in presence of different salts. Analysis by LC-MS of the five peptide sequences of Hf15 generated by trypsinization revealed that two peptides displayed homology to an uncharacterized protein 3-like from Haliotis rufescens, Haliotis asinia and H. sorenseni. The results obtained indicated that Hf15 is a novel SMP involved in shell mineralization in Haliotis fulgens. [Display omitted] •Hf15 is a novel SMP involved in shell mineralization.•Hf15 is an acidic unglycosylated protein with calcium and chitin-binding capability.•Hf15 has no homology to previously characterized SMPs.