Fusion protein bilayer fabrication composed of recombinant azurin/cytochrome P450 by the sortase-mediated ligation method

Biomolecular engineering for nanobio/bionanotechnology

Biomolecular engineering can be used to purposefully manipulate biomolecules, such as peptides, proteins, nucleic acids and lipids, within the framework of the relations among their structures, functions and properties, as well as their applicability to such areas as developing novel biomaterials, biosensing, bioimaging, and clinical diagnostics and therapeutics. Nanotechnology can also be used to design and tune the sizes, shapes, properties and functionality of nanomaterials. As such, there are considerable overlaps between nanotechnology and biomolecular engineering, in that both are concerned with the structure and behavior of materials on the nanometer scale or smaller. Therefore, in combination with nanotechnology, biomolecular engineering is expected to open up new fields of nanobio/bionanotechnology and to contribute to the development of novel nanobiomaterials, nanobiodevices and nanobiosystems. This review highlights recent studies using engineered biological molecules (e.g., oligonucleotides, peptides, proteins, enzymes, polysaccharides, lipids, biological cofactors and ligands) combined with functional nanomaterials in nanobio/bionanotechnology applications, including therapeutics, diagnostics, biosensing, bioanalysis and biocatalysts. Furthermore, this review focuses on five areas of recent advances in biomolecular engineering: (a) nucleic acid engineering, (b) gene engineering, (c) protein engineering, (d) chemical and enzymatic conjugation technologies, and (e) linker engineering. Precisely engineered nanobiomaterials, nanobiodevices and nanobiosystems are anticipated to emerge as next-generation platforms for bioelectronics, biosensors, biocatalysts, molecular imaging modalities, biological actuators, and biomedical applications.

Total chemical synthesis of the site-selective azide-labeled [I66A]HIV-1 protease

The first total chemical synthesis of the site-selective azide-labeled [I66A]HIV-1 protease is described by native chemical ligation. Chemical synthesis of azide-labeled proteins would provide useful protein tools for biochemical, biophysical or medical studies.

Site-specific immobilization of protein layers on gold surfaces via orthogonal sortases

We report a site-specific, sortase-mediated ligation to immobilize proteins layer-by-layer on a gold surface. Recombinant fluorescent proteins with a Sortase A recognition tag at the C-terminus were immobilized on peptide-modified gold surfaces. We used two sortases with different substrate specificities (Streptococcus pyogenes Sortase A and Staphylococcus aureus Sortase A) to immobilize layers of GFP and mCherry site-specifically on the gold surface. Surfaces were characterized using fluorescence and atomic force microscopy after immobilizing each layer of protein. Fluorescent micrographs showed that both protein immobilization on the modified gold surface and protein oligomerization are sortase-dependent. AFM images showed that either homogenous protein monolayers or layers of protein oligomers can be generated using appropriately tagged substrate proteins. Using Sortase A variants with orthogonal peptide substrate specificities, site-specific immobilization of appropriately tagged GFP onto a layer of immobilized mCherry was achieved without disruption of the underlying protein layer.