Marine Biominerals with a Biotechnological Future

Biomineralization is a biologically controlled process by which available inorganic ions are extracted from the medium toward the production of solid structures that offer an adaptive advantage to the producing organism. Fossilization is also a form of biomineralization. In the sea, these structures range from monolithic crystals produced by bacteria to architectured organomineral composites produced by a majority of protists, plants, and animals. Their production can originate internally in specialized organelles or occur externally, and they can perform mechanical/structural or functional/defensive roles. Most biominerals outlive their biological host and eventually accumulate through time, modifying the biogeochemistry of the ocean floor and of the lithosphere in general. This chapter is an overview of the three major types of marine biominerals (calcium carbonate, silica, heavy metals), the organisms that produce them (bacteria, cyanobacteria, protozoans, phytoplankton, seaweeds, protostomia invertebrates, deuterostomia invertebrates, fish), and their use in novel biotechnologies (industry, medicine, nanotechnology). Interest in biomineralization lies in the fact that organisms can produce intricate biominerals under mild, ambient conditions, in contrast to their production by conventional chemical synthesis. Observing why and how organisms invest in producing specific biominerals may be very rewarding as a source of bioinspiration. Biominerals are important for human health and welfare in a biotechnology era that has to face the multiple challenges of global warming, with its threats to species diversity and habitat loss.