Mussel adhesives proteins have been extensively studied as a promising alternative in bioadhesives due to their ability to provide durable anchoring under different surfaces in seawater. These charasteristics have been attributed to the presence of the reduced catechol form, 3,4-dihydroxyphenylalanine (DOPA) of its structure. However, its practical applications have been limited due to drawbacks with natural extraction. Here, a novel method have been described for site-specific chemical incorporation of l-3,4-dihydroxyphenylalanine methyl ester (l-DOPAME) into proteins, in particular Candida antartica fraction B (CAL-B) lipase. Two strategies were followed, direct conjugation of DOPA at the C-terminus on the surface of the protein, and protein conjugation with tailor-made glycopolymers (DOPA-hyaluronic acid (HA) polymers) at the N-terminus. In all cases, the characterization of the new DOPA-proteins was carried out using circular dichroism, fluorescence or mass spectrometry. An improvement in the activity (in some cases more than 2 times) or the thermostability of CAL-B (with a half live 4 fold greater in some cases) was found by the incorporation of DOPA molecules. These DOPA-proteins showed excellent underwater covalent adhesive ability on amino functionalized surfaces in aqueous media compared to other modified [e.g. tyrosine modified (TYR)] CAL-B proteins. At pH 8.5, CALB-DOPA proteins were completely adsorbed after 90 min of incubation, whereas about 10% of CALB-HA or CALB-TYR proteins were adsorbed at the same time. Native CAL-B adsorption was not observed. These results suggest a potential application of these DOPA-proteins as bioglues or bioadhesives for practical underwater applications.

Glycoderivatives are an important class of molecules with enormous relevance in numerous biological phenomena; therefore, they have a key role in the learning, understanding, and assessment of different diseases. Nanotechnology, and in particular the design of new nanomaterials, is one of the areas of greatest interest today. In this case, graphene nanomaterials represent very interesting platforms for studying glycosystems, glyconanomaterials that combine the biomolecular recognition and the characteristics of nanoscale objects in the development of early diagnosis systems, and efficient specific therapeutic modalities. In this mini-review, we discuss some results recently described in the literature on the conjugation of graphene materials and carbohydrates through the selective interaction of glycoenzymes in graphene to create new materials with biosensing applications, the development and application of sugar–graphene composites, and finally biosystems combining the properties of graphene with metallic nanoparticles and sugars for the creation of excellent glyconanomaterials as novel systems for the therapy or diagnosis of important diseases such as cancer or diabetes.

Highly stable nanocatalysts have been synthesized in aqueous medium at room temperature by the in situ formation of Pd nanoparticles (PdNPs) embedded in an enzyme net. Different parameters in the synthesis were evaluated such as T, ratio enzyme/Pd salt, using Candida antarctica B lipase (CALB) as enzyme. In all different CALB/ PdNPs hybrids synthesized, crystalline Pd(0) as a unique metallic species was confirmed by XRD. Spherical nanoparticles were obtained with diameter size from 2 to 11 nm, depending on the synthetic conditions. These CALB/PdNPs hybrids were employed as catalyst in the CÀ N/Heck reaction cross-coupling cascade for the synthesis of substituted azaindoles using various amino-o-bromopyridines as starting material in moderate conditions. The best conversion with high selectivity of the formation of C2-substituted azaindoles was obtained at 90°C using dioxane containing 5% water as the best reaction solvent from the different solvents tested, using potassium carbonate as milder base. The catalysis with these CALB/PdNPs hybrids at these conditions was also successful in the production of several isomers of azaindoles, especially relevant for the formation of the 7-azaindole, where 65% conversion was obtained, a very good improvement when compared to the reported protocol using a Pd 2 (dba) 3 /XPhos/t-BuONa catalytic system.