Glucose Oxidase Mutants for Thermal and Acid Stability in Feed Processing

The patent applies parameter changes by introducing specific amino acid mutations (G203C, E219P, S338P, E361P, A419I) at critical positions in the glucose oxidase protein structure. These mutations alter the enzyme's molecular parameters to enhance its thermal stability, allowing it to maintain activity at elevated temperatures during feed granulation processes while preserving catalytic function.

The patent creates composite enzymatic systems by combining multiple mutation strategies (single point mutations, double mutations, triple mutations) to achieve synergistic effects. The composite mutant enzymes exhibit enhanced thermal and acid stability simultaneously, resolving the contradiction between temperature resistance and activity maintenance.

The patent modifies the enzyme's chemical parameters by introducing mutations (particularly E361P, A419I, and combinations) that alter the protein's charge distribution and structural conformation. These parameter changes enable the enzyme to resist acid denaturation in the gastrointestinal environment while maintaining catalytic activity for glucose oxidation.

The patent applies preliminary anti-action by pre-introducing stabilizing mutations that counteract acid-induced denaturation before the enzyme is exposed to acidic conditions. The mutant enzymes have pre-established structural resilience that prevents acid from compromising their activity, allowing them to function reliably in acidic feed processing and gastrointestinal environments.

The patent applies segmentation by dividing the complex mutation strategy into modular components: single point mutations (G203C, E219P, S338P, E361P, A419I), double mutations (e.g., E361P/G203C), triple mutations (e.g., E361P/A419I/G203C), and six-point mutations. This segmentation allows systematic construction and testing of mutants, managing complexity through organized progression from simple to complex mutations.

The patent applies preliminary action by pre-planning and pre-testing individual mutations and their combinations before finalizing the enzyme construct. The systematic approach involves preliminary characterization of single mutants, then building upon those results to create higher-order mutants, thereby managing construction complexity through staged development.