A lipase with broad temperature range from an alkaliphilic gamma‐proteobacterium isolated in Greenland

A gamma‐proteobacterium related to the genera <i>Alteromonadales</i> and <i>Pseudomonadales</i>, isolated from a cold and alkaline environment in Greenland, has been shown to produce a lipase active between 5°C and 80°C, with optimal activity at 55°C and pH 8. PCR‐based screening of genomic DNA from the isolated bacterium, followed by genome walking, resulted in two complete open reading frames, which were predicted to encode a lipase and its helper protein, a lipase foldase. The amino acid sequence derived for the lipase showed resemblance to lipases from <i>Pseudomonas</i>, <i>Rhodoferax, Aeromonas</i> and <i>Vibrio</i>. The two genes were cloned into different expression systems in <i>E. coli</i> with or without a putative secretion sequence, but despite the fact that both recombinant lipase and lipase foldase were observed on SDS–PAGE, no recombinant lipase activity was detected. Attempts to refold the recombinant lipase <i>in vitro</i> using a purified lipase foldase remained unsuccessful.