Esterases of xylan-degrading microorganisms: production, properties, and significance.

This review focuses on the description of recently discovered esterase enzymes involved in xylan degradation (acetyl xylan, feruloyl, and p-coumaroyl esterases). The occurrence of these enzymes in various microorganisms, assays used for determination of their activity, induction and production on different substrates, interaction with other xylanolytic enzymes, mode of action, substrate specificity, and biochemical characteristics are presented. The nature of substrates on which acetyl xylan esterase, feruloyl, and p-coumaroyl esterase are active and their role in xylan hydrolysis is emphasized. The potential applications of xylan-debranching esterases are outlined and their significance to applied microbiology is discussed.