Our recent work demonstrates that certain flavoproteins can catalyze the redox activation of Pt(IV) prodrug complexes under light irradiation. Herein, we used site-directed mutagenesis on mini singlet oxygen generator (mSOG) to modulate photocatalytic activity this flavoprotein toward two model substrates. Among prepared mutants, Q103V mSOG displayed enhanced catalytic efficiency as a result it...

A DNA double-strand break can be efficiently repaired in Escherichia coli if an oligodeoxyribonucleotide is provided to direct the repair. The oligonucleotide must be at least 20 residues long and have a sequence identical to sequences flanking the break. The phenomenon can be used to introduce defined mutations into DNA in the area of a double-strand break. To obtain mutants, the oligonucleoti...

The active site and substrate-binding mode of MD-ACO1 (Malus domestica Borkh. 1-aminocyclopropane-1-carboxylate oxidase) have been determined using site-directed mutagenesis and comparative modelling methods. The MD-ACO1 protein folds into a compact jelly-roll motif comprised of eight a-helices, 12 b-strands and several long loops. The active site is well defined as a wide cleft near the C-term...

The Escherichia coli melAB promoter has been cloned on a short DNA fragment and subjected to deletion mutagenesis, random mutagenesis and site-directed mutagenesis. In previous work we had shown that expression from the melAB promoter is triggered by melibiose and that this requires the MelR transcription activator. Melibiose-dependent expression is suppressed by deletions that remove both DNA-...

tyrosinase (ec: 1.14.18.1) is a copper - containing enzyme which is distributed in all domains of life such as prokaryote, eukaryote, mammals, invertebrates and plants. tyrosinase catalyzes the oxidation of monophenols to diphenols and diphenols to o-quinones . the tyrosinase crystallographic data shows two histidine -rich regions named cua and cub. a loop containing residues m374, s375 and v37...