Enzyme binding to detect carbohydrate expression in tissue sections. 1. Native and cross-linked glucose oxidase

Area of Science:

• Biochemistry
• Histochemistry
• Enzymology

Background:

• Enzymes can function as specific probes for localizing macromolecular substrates in tissue sections.
• Glucose oxidase is a double-headed enzyme capable of binding to glucose.

Purpose of the Study:

• To utilize glucose oxidase as a histochemical probe for identifying and localizing beta-glucosyl groups in paraffin-embedded tissue sections.
• To evaluate the efficacy of native and polymerized glucose oxidase for this purpose.

Main Methods:

• Paraffin sections were incubated with native and polymerized glucose oxidase.
• Polymerization of glucose oxidase was achieved using glutaraldehyde to create soluble polymers with multiple active binding sites.
• Staining intensity was analyzed in relation to enzyme concentration, incubation time, temperature, and pH.

Main Results:

• Polymerized glucose oxidase demonstrated significantly higher effectiveness (approximately 100-fold) compared to the native form.
• The intensity of histochemical staining correlated directly with enzyme concentration, incubation duration, temperature, and pH.
• Glucose oxidase effectively identified beta-glucosyl groups in tissue sections.

Conclusions:

• Polymerized glucose oxidase is a sensitive and effective histochemical reagent for identifying glucose-containing structures.
• This enzymatic probe has substantial potential for analyzing normal tissues and detecting abnormal carbohydrate deposition in pathological conditions.
• The glucose oxidase system provides a valuable model for histochemical analysis.