Properties, structure, and applications of microbial sterol esterases

Area of Science:

• Biochemistry
• Enzymology
• Microbiology

Background:

• Carboxylic ester hydrolases include sterol esterases (EC 3.1.1.13), or cholesterol esterases, which hydrolyze sterol esters.
• Mammalian cholesterol esterases are crucial for lipid metabolism and cholesterol absorption.
• Microbial extracellular sterol esterases offer broad stability and substrate specificity, making them industrially relevant.

Purpose of the Study:

• To review available information on microbial sterol esterases.
• To analyze their origin, production, purification, and heterologous expression.
• To investigate their structure, stability, and substrate specificity for potential applications.

Main Methods:

• Gathering and reviewing existing literature on microbial sterol esterases.
• Conducting a comprehensive phylogenetic analysis of cholesterol esterase sequences.
• Analyzing properties such as origin, production, purification, expression, structure, stability, and substrate specificity.

Main Results:

• Microbial sterol esterases, particularly from Pseudomonas and Candida rugosa, are commercially exploited.
• These enzymes often belong to the α/β-hydrolase superfamily with a conserved catalytic triad.
• Extracellular variants exhibit desirable properties like broad stability and specificity.

Conclusions:

• Microbial sterol esterases possess significant potential for industrial applications due to their unique properties.
• Further characterization and research are needed to fully exploit these enzymes.
• Phylogenetic analysis provides insights into their evolutionary relationships and functional diversity.