Nucleation of bone mineral hydroxylapatite on genetically engineered phage
H. Xu, B. Cao, C. Mao
University of Oklahoma, US
Keywords: bone, hydroxylapatite, mineralization, phage, nanofibers
Abstract:Dentin matrix protein 1 (DMP1) is one of the non-collagenous extracellular matrix proteins that can control the mineralization in teeth. Filamentous M13 phage is a virus that specifically infects bacteria and is non-toxic to human beings. Two peptides derived from DMP-1, ESQES and QESQSEQDS, were separately displayed on the side wall of filamentous phage. These two peptides were reported to be able to nucleate hydroxylapatite (HAP). We allow the phages displaying these two functional peptides to interact with the HAP supersaturated solution. Microscopy characterization of the mineralized phage shows that HAP is nucleated on the phage. This result indicates that the two DMP-1 derived peptides can nucleate HAP when displayed on the phage as they do in their free forms. We also conduct the co-assembly of the phages displaying the two peptides in the presence of the HAP precursor solution. We expect that the co-assembly will lead to a mineralized matrix due to the interaction between the peptides displayed on phage. The mineralized phage nanofibers may serve as a building block for further assembly into a larger material. Our method may provide a new approach to the formation of mineralized protein matrix and production of artificial bone biomaterials.