Biomimetic　mineralization　has　emerged　as　a　novel　tool　for　generating　excellent　supports　for　enzyme　stabilization.　In　this　work,　protamine　was　used　to　induce　titanium　(IV)　bis(ammonium　lactato)　dihydroxide　(Ti-BALDH)　into　titania　nanoparticles.　This　biomimetic　titanification　process　was　adopted　for　laccase　immobilization.　Laccase-biotitania　biocatalyst　was　prepared　and　the　effect　of　different　parameters　(buffer　solution,　titania　precursor　concentration,　protamine　concentration,　and　enzyme　loading)　on　the　encapsulation　efficiency　and　recovery　of　laccase　were　evaluated.　Compared　with　free　laccase,　the　thermal　and　pH　stability　of　immobilized　laccase　were　improved　significantly.　In　addition,　laccase　loaded　on　titania　was　effective　at　enhancing　its　storage　stability.　After　seven　consecutive　cycles,　the　immobilized　laccase　still　retained　51%　of　its　original　activity.　Finally,　laccase-biotitania　biocatalysts　showed　good　performance　on　decolorization　of　malachite　green　(MG),　which　can　be　attributed　to　an　adsorption　and　degradation　effect.　The　intermediates　of　the　MG　degradation　were　identified　by　gas　chromatography-mass　spectrometry　(GC–MS)　analysis,　and　the　most　probable　degradation　pathway　was　proposed.　This　study　provides　deeper　understanding　of　the　laccase-biotitania　particles　as　a　fast　biocatalyst　for　MG　decolorization.　©　2018　The　Society　for　Biotechnology,　Japan