Compound modification method for laccase and applications of modified laccase

Abstract

The invention discloses a compound modification method for laccase and applications of the modified laccase. The compound modification method for laccase comprises the following steps: carrying out carboxy modification, namely, sequentially adding a laccase inhibitor, a carboxy activating agent and a modifying agent into laccase water solution for reaction, and after complete reaction, carrying out dialysis on the reaction system, thus obtaining carboxy modified laccase; and carrying out amino modification, namely, sequentially adding an amino activating agent and a modifying agent into the carboxy modified laccase solution in S1 for reaction, and carrying out dialysis after the complete reaction, thus obtaining the compound modified laccase. According to the compound modification for laccase provided by the invention, compound modification is carried out on carboxyl and amino on side chains of amino acid residues or terminal amino acid of laccase, meanwhile, the active groups, namely,carboxy and amino on the chains of laccase are protected, under the premise that the active central sites of laccase are protected from being influenced, the activity and stability of laccase are changed, the obtained compound modified laccase can obviously improve the pulping and papermaking properties of modified fibers, and therefore, a novel path is provided for the recycling of fibers.

Description

technical field [0001] The invention belongs to the technical field of laccase modification, and more specifically relates to a method for compound modification of laccase and its application. Background technique [0002] Emperor Bamboo Grass is a large plant with the characteristics of strong adaptability, strong tillering, fast growth, high yield, rich nutrition, high fiber content, and can be harvested for many years. It is a very valuable non-wood fiber pulping and papermaking Raw materials, but the strength of the paper produced is low, in order to improve its utilization level and use value, it is necessary to modify it. In terms of fiber modification, the biomodification of laccase mediator system is currently a research hotspot and difficulty. The biomodification of laccase mediator system has many advantages, such as mild reaction conditions, less fiber damage, and the use of environmentally friendly drugs, etc. , but because laccase has amino acid residues or ter...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved in the present invention is to overcome the defects and deficiencies in the prior art that the modification effect of laccase modification activity is not good, and provide a method for compound modification of laccase, by simultaneously modifying the laccase amino acid residue side chain Amino and carboxyl, greatly improving the modification effect of chemical modification