Cloning and sequence analysis of the lipase and lipase chaperone-encoding genes from Acinetobacter calcoaceticus RAG-1, and redefinition of a Proteobacterial lipase family and an analogous lipase chaperone family

Production of Serine Protease of Aeromonas sobria Is Controlled by the Protein Encoded by the Gene Lying Adjacent to the 3′ End of the Protease Gene

“…Several periplasmic chaperones such as Skp acting on OmpA (25), LipB on lipase (8,30) and FaeE on fimbriae protein (1) have been reported. However, the mechanisms of action of these intramolecular chaperones have not been fully elucidated.…”

Enhancement of lipase activity from Acinetobacter species SY-01 by random mutagenesis and the role of lipase-specific chaperone

“…Since the movements of the loop between strand ␤4 and helix ␣2 (Acinetobacter species SY-01 lipase aa residues 99-106), of the oxyanion loop (Acinetobacter species SY-01 lipase aa residues 64-70), and of the lid region are correlated [16], the changed Gly residue from the conserved Ala 102 residue might play an important stabilizing role during opening of the lid of these lipases [17]. Moreover, Ala 102 and Ser 103 residues are the conserved turn residues located between strand ␤4 and helix ␣4 and highly conserved in structure analysis of the group I Proteobacterial lipases, based on comparisons of deduced aa sequences of the mature proteins [17,18]. Tetra peptide motif Gly-Hyd-X-Gly (Hyd = Met, Leu, Val) located between strand ␤3 and helix ␣4 were highly conserved in group I.1 and I.2 of bacterial lipases and contributed to stabilization of lipase.…”

“…Most of the conserved residues had significant function in the acyl portion of the substrate pocket and mutation of these residues resulted in an improvement of the selectivity for the short-and long-chain substrates, and decreasing selectively for middle-chain substrates and an increase in lipase activity [17][18][19].…”

Prospecting for novel lipase genes using PCR a aThe GenBank accession number for the sequence reported in this paper is AF421484.

“…A consequence of this toxicity may be that bacteria containing lipase genes are poorly represented or absent from an expression library based on environmental DNA. Functional expression of the lipase protein may also require a helper gene or foldase (Jaeger et al, 1994 ;Sullivan et al, 1999). Incompatibility of transcription and translation apparatus between the organism producing lipase and a heterologous host such as E. coli also limits the usefulness of expression libraries for lipase gene prospecting.…”