Detoxifying Cyanides Using Cyanase Enzyme Complexes Composed of Carbonic Anhydrase via Irreversible Covalent Bonds.

Cyanase is a possible solution to reduce the environmental impact of cyanide. However, the enzyme's dependence on HCO3- limits its industrial applications. To overcome this problem, carbonic anhydrase is utilized in this study. Three types of Catcher/Tag systems were introduced into the cyanase (psCYN) from Pseudomonas stutzeri and the carbonic anhydrase (hmCA) from Hydrogenovibrio marinus to construct enzyme complexes via irreversible covalent bonds. Initially, a cyanase complex with the aid of scaffolding proteins was designed. The results of cyanase complexes using scaffolding proteins were similar to or inferior to those of the two free enzymes. To address this, the two enzymes were manipulated to form a direct bioconjugation without the need for scaffolding proteins. The two enzymes forming a direct conjugation showed activity more than 2.5 times higher than that of cyanase alone. In conclusion, this outcome will contribute to solving problems related to residual cyanides in food and the environment.

The increased efficiency of porphyran hydrolysis by constructing a multifunctional enzyme complex from marine microorganisms.

Porphyran, a polysaccharide composed of red algae, is a source of a multifunctional oligosaccharide material and raw biomass with various physiological activities. The glycolysis of porphyrans into oligosaccharides through various porphyranases is an approach for obtaining high-quality and promising alternative resources. In this study, porphyran was extracted from Porphyra yezoensis and used as a research substrate. We also established an efficient hydrolysis method using an enzymatic complex obtained through cohesin-dockerin interactions that degrade natural polysaccharides. The cohesion-dockerin interaction is designed to genetically bind the dockerin module to the end of an existing enzyme and then attach the cohesin module to obtain a protein complex. The designed protein complex has been shown to further increase the activity on the substrate, which can be considered a useful method to obtain efficient oligosaccharides or monosaccharides through hydrolysis of red algae for bioresources.