Karl-Erich Jaeger

Classification of Lipolytic Enzymes from Bacteria

Lipolytic enzymes including lipases and esterases comprise a versatile group of enzymes with diverse amino acid sequences but related three-dimensional structures. Despite the large number of bacterial lipolytic enzymes so far identified (~5000), only a small portion (<10%) was cloned, expressed, and experimentally studied. Twenty years ago, Arpigny and Jaeger published a seminal study which systematically grouped bacterial lipolytic enzymes into eight families according to similarity of their amino acid sequences and physiological properties (Arpigny and Jaeger, Biochem J 343:177–183, 1999). Here, we present a comprehensive overview as an extension of the original classification covering all 19 presently known families of lipolytic enzymes. The conserved features of sequences and structures are described for all families in order to simplify the assignment of newly discovered lipolytic enzymes to the respective family. Furthermore, we have correlated the biochemical properties of some enzymes with the nature of the often extremophilic microorganism from which the respective enzyme was isolated. This may help to identify lipase families with potential as biocatalysts in industrial applications. As an example, family XV enzymes are stable and active at elevated temperatures; thus, enzymes of this family represent a potential source for novel biocatalysts.