Biomineralization of metal oxide utilizes biomolecular substances, such as peptides and proteins, to induce mineralization of metal precursors in a mild aqueous solution. In this study, we investigated biomineralization of an abiological substance, titanium dioxide (TiO(2)), by oligo(L-lysine). Specifically, we systemically studied the influence of the number of consecutive lysine on TiO(2) precipitation. Oligo(L-lysine) was chosen as a homopeptide lysine source whose lysine quantity was adjusted. When oligo(L-lysine) contains more than three consecutive lysine, it induces notably fast precipitation, while single and dilysine do not readily form TiO(2) precipitates. Precipitation of TiO(2) was promoted with the length of oligo(L-lysine). The oligo(L-lysine) was associated with TiO(2) precipitate, which was confirmed by spectroscopic and thermogravitational analyses. The outcomes of this research provide a plausible rationale for explaining precipitation of the Ti precursor that is highly dependent on peptide sequences. (C) 2011 Elsevier B.V. All rights reserved.