Rutinosidase and other diglycosidases: Rising stars in biotechnology

Copper formate-lysine nanoparticles with polyphenol oxidase-like activity for the detection of epinephrine

Laccase is an enzyme known for its eco-friendly uses in environmental cleanup and biotechnology. However, it has limitations such as low stability, high cost, and complex recycling. So, there is a need for laccase mimics that can effectively imitate its properties. Herein, we created copper formate-lysine nanoparticles (Cuf-Lys) that mimic laccase's activity. The developed Cuf-Lys demonstrated remarkable polyphenol oxidase-like activity, stability, and recyclability, making them suitable for the fabrication of efficient colorimetric sensors for the detection of epinephrine. These sensors had a specific response and could accurately measure epinephrine concentrations ranging from 2.5 to 50 μM, with a detection limit as low as 1 μM. Furthermore, the biosensor demonstrated high sensitivity and selectivity when applied to the detection of rutin. The limit of detection for rutin was determined to be 0.16 μM while in the linear concentration range of 0.25 to 150.0 μM. We believe that Cuf-Lys provide a new route for the design of laccase mimics, showing potential applications for biomedical diagnosis and environmental monitoring.

A novel diglycosidase for the transformation of naringin to naringenin and neohesperidose

A novel fungal diglycosidase that transforms naringin into naringenin and neohesperidose, a rare biotransformation, has been purified to homogeneity using a simple procedure involving precipitation of the enzyme from the culture filtrate of the fungal strain using 80 % saturation of ammonium sulphate, dissolving the precipitate in minimum volume of the buffer and dialysing that against the buffer. The purified enzyme gives single protein bands of molecular mass 64.6 kDa in SDS-PAGE analysis. The purity of the enzyme has been further confirmed by the appearance of single protein band in native page analysis. Using naringin as the substrate, the diglycosidase has Km and kcat values of 0.20 m mol L-1 and 0.66 s-1, respectively, at pH 4.0 and 313 K. The specific activity of the purified enzyme using naringin as the natural substrate is 1.018 katal/kg. The diglycosidase also transforms rutin into quercetin and rutinose but has no effect on hesperidin. The feasibilities of preparing neohesperidose from naringin and rutinose from rutin on milligram scales using the pure enzyme have been demonstrated. These results open the way for developing an enzymatic process for preparation of neohesperidose from naringin. The reported diglycosidase has immense future applications in food and pharmaceutical industries.

Discovery of Potent Glycosidases Enables Quantification of Smoke-Derived Phenolic Glycosides through Enzymatic Hydrolysis

When grapes are exposed to wildfire smoke, certain smoke-related volatile phenols (VPs) can be absorbed into the fruit, where they can be then converted into volatile-phenol (VP) glycosides through glycosylation. These volatile-phenol glycosides can be particularly problematic from a winemaking standpoint as they can be hydrolyzed, releasing volatile phenols, which can contribute to smoke-related off-flavors. Current methods for quantitating these volatile-phenol glycosides present several challenges, including the requirement of expensive capital equipment, limited accuracy due to the molecular complexity of the glycosides, and the utilization of harsh reagents. To address these challenges, we proposed an enzymatic hydrolysis method enabled by a tailored enzyme cocktail of novel glycosidases discovered through genome mining, and the generated VPs from VP glycosides can be quantitated by gas chromatography-mass spectrometry (GC-MS). The enzyme cocktails displayed high activities and a broad substrate scope when using commercially available VP glycosides as the substrates for testing. When evaluated in an industrially relevant matrix of Cabernet Sauvignon wine and grapes, this enzymatic cocktail consistently achieved a comparable efficacy of acid hydrolysis. The proposed method offers a simple, safe, and affordable option for smoke taint analysis.

Rutinosides-derived from Sarocladium strictum 6-O-α-rhamnosyl-β-glucosidase show enhanced anti-tumoral activity in pancreatic cancer cells

BACKGROUND

Low targeting efficacy and high toxicity continue to be challenges in Oncology. A promising strategy is the glycosylation of chemotherapeutic agents to improve their pharmacodynamics and anti-tumoral activity. Herein, we provide evidence of a novel approach using diglycosidases from fungi of the Hypocreales order to obtain novel rutinose-conjugates therapeutic agents with enhanced anti-tumoral capacity.

RESULTS

Screening for diglycosidase activity in twenty-eight strains of the genetically related genera Acremonium and Sarocladium identified 6-O-α-rhamnosyl-β-glucosidase (αRβG) of Sarocladium strictum DMic 093557 as candidate enzyme for our studies. Biochemically characterization shows that αRβG has the ability to transglycosylate bulky OH-acceptors, including bioactive compounds. Interestingly, rutinoside-derivatives of phloroglucinol (PR) resorcinol (RR) and 4-methylumbelliferone (4MUR) displayed higher growth inhibitory activity on pancreatic cancer cells than the respective aglycones without significant affecting normal pancreatic epithelial cells. PR exhibited the highest efficacy with an IC50 of 0.89 mM, followed by RR with an IC50 of 1.67 mM, and 4MUR with an IC50 of 2.4 mM, whereas the respective aglycones displayed higher IC50 values: 4.69 mM for phloroglucinol, 5.90 mM for resorcinol, and 4.8 mM for 4-methylumbelliferone. Further, glycoconjugates significantly sensitized pancreatic cancer cells to the standard of care chemotherapy agent gemcitabine.

CONCLUSIONS

αRβG from S. strictum transglycosylate-based approach to synthesize rutinosides represents a suitable option to enhance the anti-proliferative effect of bioactive compounds. This finding opens up new possibilities for developing more effective therapies for pancreatic cancer and other solid malignancies.