Abstract
Two biocatalytically produced inorganic biomaterials show great potential for use in regenerative medicine but also other medical applications: bio-silica and bio-polyphosphate (bio-polyP or polyP). Biosilica is synthesized by a group of enzymes called silicateins, which mediate the formation of amorphous hydrated silica from monomeric precursors. The polymeric silicic acid formed by these enzymes, which have been cloned from various siliceous sponge species, then undergoes a maturation process to form a solid biosilica material. The second biomaterial, polyP, has the extraordinary property that it not only has morphogenetic activity similar to biosilica, i.e., can induce cell differentiation through specific gene expression, but also provides metabolic energy through enzymatic cleavage of its high-energy phosphoanhydride bonds. This reaction is catalyzed by alkaline phosphatase, a ubiquitous enzyme that, in combination with adenylate kinase, forms adenosine triphosphate (ATP) from polyP. This article attempts to highlight the biomedical importance of the inorganic polymeric materials biosilica and polyP as well as the enzymes silicatein and alkaline phosphatase, which are involved in their metabolism or mediate their biological activity.
Highlights
The oxides of two physiological, non-carbon elements have aroused particular interest in manufacturing tissue engineering scaffolds: silicon and phosphorus
This is important with regards to the potential use ofminerals for the regeneration of bone tissue, since only the amorphous minerals such as amorphous silica, amorphous calcium carbonate (ACC) and amorphous calcium phos
Besides the enzymes that synthesize the polymeric material, such as silicatein, which forms silica from monomeric precursors, the enzymes that degrade these materials are likewise important. Some of these enzymes, such as the bacterial polyP kinases, show both polymerizing and depolymerizing activity [13] or are involved in regeneration of metabolic energy needed for tissue function [3]. Due to their prominent role in the formation and function of materials that are of interest in biomineral-based approaches in regenerative medicine, the two basic enzymes present in animals, silicatein and alkaline phosphatase (ALP), as well as their application in tissue repair are discussed in more detail
Summary
The oxides of two physiological, non-carbon elements have aroused particular interest in manufacturing tissue engineering scaffolds: silicon and phosphorus The oxides of these elements and their polymers, silica and polyphosphate (polyP), are involved in the formation of the biomineral skeletons of a large number of animal species, from sponges (silica) to vertebrates (calcium phosphate and hydroxyapatite). Amorphous silica (“biosilica”) is synthesized by the enzyme silicatein (formation of the silica skeleton of the siliceous sponges; [12]), ACC by the enzyme carbonic anhydrase [10] and ACP by the enzyme alkaline phosphatase (ALP) [3]. Besides the enzymes that synthesize the polymeric material, such as silicatein, which forms silica from monomeric precursors, the enzymes that degrade these materials are likewise important Some of these enzymes, such as the bacterial polyP kinases, show both polymerizing and depolymerizing activity [13] or are involved in regeneration of metabolic energy needed for tissue function [3]. Due to their prominent role in the formation and function of materials that are of interest in biomineral-based approaches in regenerative medicine, the two basic enzymes present in animals, silicatein and ALP, as well as their application in tissue repair are discussed in more detail
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
