Gene cloning and molecular characterization of the Talaromyces thermophilus lipase Catalyzed efficient hydrolysis and synthesis of esters

摘要

A genomic bank from Talaromyces thermophilus fungus was constructed and screened using a previously isolated fragment lipase gene as probe. From several clones isolated, the nucleotide sequence of the lipase gene (TTL gene) was completed and sequenced. The TTL coding gene consists of an open reading frame (ORF) of 1083. bp encoding a protein of 269 Aa with an estimated molecular mass of 30. kDa. The TTL belongs to the same gene family as Thermomyces lanuginosus lipase (TLL, Lipolase?), a well known lipase with multiple applications. The promoter sequence of the TTL gene showed the conservation of known consensus sequences PacC, CreA, Hap2-3-4 and the existence of a particular sequence like the binding sites of Oleate Response Element (ORE) and Fatty acids Responsis Element (FARE) which are similar to that already found to be specific of lipolytic genes in Candida and Fusarium, respectively. Northern blot analysis showed that the TTL expression was much higher on wheat bran than on olive oil as sole carbon source. Compared to the Lipolase?, this enzyme was found to be more efficient for the hydrolysis and the synthesis of esters; and its synthetic efficiency even reached 91.6% from Waste Cooking Oil triglycerides.