Purification and properties of human serum esterase

Area of Science:

• Biochemistry
• Enzymology

Background:

• Human serum esterase plays a role in hydrolyzing various substrates.
• Understanding the specific properties and tissue distribution of serum esterase is crucial for its biochemical characterization.

Purpose of the Study:

• To purify human serum esterase.
• To characterize the substrate specificity and inhibition patterns of the purified enzyme.
• To generate an antiserum for further immunological investigation.

Main Methods:

• Affinity column chromatography utilizing p-trimethylammoniumanilinium dichloride covalently linked to Sepharose 4B for enzyme purification.
• Enzyme activity assays using benzoylcholine and tributyrin as substrates.
• Kinetic analysis to determine Km values.
• Antiserum production in rabbits and subsequent inhibition assays.

Main Results:

• Human serum esterase was successfully purified.
• The purified esterase hydrolyzed both benzoylcholine and tributyrin.
• p-Trimethylammoniumanilinium dichloride exhibited competitive inhibition with benzoylcholine and non-competitive inhibition with tributyrin.
• The Km values for tributyrin and benzoylcholine were determined.
• The generated antiserum specifically inhibited human serum esterase activity but not esterases from human liver, muscle, or adipose tissue.

Conclusions:

• The study successfully purified and characterized human serum esterase.
• The findings indicate distinct kinetic properties and substrate preferences for the purified enzyme.
• The specific antiserum provides a valuable tool for distinguishing serum esterase from other tissue esterases.