해양 메타게놈으로부터 신규의 지질분해효소 분리

Abstract

Metagenomic libraries of various marine sediments collected from a seamount near hydrothermal vent, Artic coast (Dasan station) and inter tidal flat of Kangwha island were constructed using a fosmid vector. The total size of the metagenomic library was estimated to about 8 Gb (more than 200,000 clones). The library was screened for the lipolytic activity by plating the clones on TBN plate, and as a result, eighteen positive clone forming a halo were obtained. The genes representing the lipolytic activities were cloned. The sequence analysis revealed that all of 18 genes contained an oxyanion hole (XG) and an active-site (GXSXG) consensus region, and showed a significant similarity to α/β hydrolase family, essentially esterase/lipases. In an attempt to expression the esterase/lipase genes in E. coli, most of those enzymes were not produced in a soluble form. Several approaches to resolve the solubility issue are under progress.