Biofilm formation is a molecular assembly process occurring at interfaces, such as in bioleaching processes. The real time monitoring of the marker bands of amide I/amide II by FTIR microspectroscopy during Acidithiobacillus ferrooxidans colonization on chalcopyrite surfaces revealed the central role of lipids, proteins and nucleic acids in bacterial cell attachment to copper sulfide surfaces. The Raman and FTIR spectra of the interactions of Acidithiobacillus ferrooxidans with bornite are also reported.