Understanding the functional properties of bio-inorganic nanoflowers as biocatalysts by deciphering the metal-binding sites of enzymes.

The biomineralisation of metal phosphates is a promising approach to develop more efficient nanobiocatalysts; however, the interactions between the protein and the inorganic mineral are poorly understood. Elucidating which protein regions most likely participate in the mineral formation will guide the fabrication of more efficient biocatalysts based on metal-phosphate nanoflowers. We have biomineralised the lipase from Thermomyces lanuginosus using three calcium, zinc and copper phosphates to fabricate different types of bio-inorganic nanoflowers.

Study of the physicochemical interactions between Thermomyces lanuginosus lipase and silica-based supports and their correlation with the biochemical activity of the biocatalysts.

The interactions between Thermomyces lanuginosus lipase (TLL) and phenyl silica-based supports affect the immobilization mechanisms and their catalytic behavior. The modulation of phenyl groups density on the silica surface and porous characteristics were determined by TGA, FTIR, Si NMR and N adsorption porosimetry. The correlation of the affinity constant and maximum adsorption capacity with the lixiviation results allowed determine differences in the enzyme adsorption mechanism in function of the immobilization pH and phenyl groups density.

Structure-activity relationships on the study of β-galactosidase folding/unfolding due to interactions with immobilization additives: Triton X-100 and ethanol.

Improving the enzyme stability is a challenge for allowing their practical application. The surfactants are stabilizing agents, however, there are still questions about their influence on enzyme properties. The structure-activity/stability relationship for β-galactosidase from Bacillus circulans is studied here by Circular Dichroism and activity measurements, as a function of temperature and pH.

Relationship between sol-gel conditions and enzyme stability: a case study with β-galactosidase/silica biocatalyst for whey hydrolysis.

The sol-gel process has been very useful for preparing active and stable biocatalysts, with the possibility of being reused. Especially those based on silica are well known. However, the study of the enzyme behavior during this process is not well understood until now and more, if the surfactant is involved in the synthesis mixture.

A high-throughput scintillation proximity-based assay for human DNA ligase IV.

Ionizing radiation (IR) and certain chemotherapeutic drugs are designed to generate cytotoxic DNA double-strand breaks (DSBs) in cancer cells. Inhibition of the major DSB repair pathway, nonhomologous end joining (NHEJ), will enhance the cytotoxicity of these agents. Screening for inhibitors of the DNA ligase IV (Lig4), which mediates the final ligation step in NHEJ, offers a novel target-based drug discovery opportunity.

High-throughput identification of inhibitors of human mitochondrial peptide deformylase.

The human mitochondrial peptide deformylase (HsPDF) provides a potential new target for broadly acting antiproliferative agents. To identify novel nonpeptidomimetic and nonhydroxamic acid-based inhibitors of HsPDF, the authors have developed a high-throughput screening (HTS) strategy using a fluorescence polarization (FP)-based binding assay as the primary assay for screening chemical libraries, followed by an enzymatic-based assay to confirm hits, prior to characterization of their antiproliferative activity against established tumor cell lines. The authors present the results and performance of the established strategy tested in a pilot screen of 2880 compounds and the identification of the 1st inhibitors.