Biopanning Phage Display Libraries in Homogeneous Solution for Identification of Biomineralization Peptides of TiO

• Published in: Journal of the Mexican Chemical Society 2024-09, Vol.68 (4), p.624-635
• Main Authors: Hernández-Gordillo, Armin, Hernández-Arana, Andrés, Vera-Robles, L. Irais
• Format: Article
• Language: English
• ISSN: 1870-249X; 2594-0317
• DOI: 10.29356/jmcs.v68i4.2262

Peptides and proteins rich in positively charged residues have been the most frequently reported for TiO2 biomineralization since their identification is based on peptide screening on its negatively charged surface. To achieve optimum interaction of the peptides with the biomimetic synthesis precursors rather than interaction with the final product, in this work, a selection of peptides with biomineralization activity was proposed by performing a biopanning directly on the precursor Titanium(IV) bis(ammonium lactate) dihydroxide (TiBALDH). Using two phage display libraries (12- and 7-mer) in different buffer systems, four possible sequences with biomineralization activity of TiO2 were identified: TNWQALAYMQRH (TN), ENHWSLSTLMSS (EN), GLHTSATNLYLH (GL), TWYPNRPPILEL (TW). The selection of buffer and concentration of TiBALDH were vital for a reliable identification. Synthetic peptides with sequences TN and EN, were selected for in vitro biomineralization of TiO2. Both peptides were able to form anatase nanoparticles at room temperature. However, the EN sequence showed lower activity than TN, specially in acetate buffer, requiring a higher concentration to initiate biomineralization. These changes in reactivity can be attributed principally to different states of protonation of the residues mainly due to the glutamic acid in EN.  Although the secondary structure determined by circular dichroism results in disordered chains, a common motif could be identified between the two peptides -pol-pol-W-pol-x-x-x-x-M-, where the W and M residues match. The results provide new possibilities for using combinatorial techniques to find new biological templates for nanomaterial synthesis.   Resumen. Péptidos y proteínas ricas en residuos con carga positiva han sido frecuentemente reportados para la biomineralización de TiO2, ya que su identificación se basa en la detección de péptidos sobre su superficie con carga negativa. Para alcanzar una interacción óptima del péptido con el precursor biomimético, en lugar de la interacción con el producto final, en este trabajo, se propuso realizar un biotamizado empleando el precursor dihidroxilactatotitanato(IV) de bis-amonio (TiBALDH) para seleccionar péptidos con actividad de biomineralización. Empleamos dos librerías de fago desplegado (12 y 7 residuos) en diferentes soluciones amortiguadoras, identificando cuatro posibles secuencias con actividad biomineralizante de TiO2: TNWQALAYMQRH (TN), ENHWSLSTLMSS (EN), GLHTSATNLYLH (GL), T