title: The short form of the recombinant CAL-A-type lipase  UM03410 from the smut fungus Ustilago maydis exhibits  an inherent trans-fatty acid selectivity.
abstract: The Ustilago maydis lipase UM03410 belongs to the mostly unexplored Candida antarctica lipase (CAL-A) subfamily. The two lipases with [corrected] the highest identity are a lipase from Sporisorium reilianum and the prototypic CAL-A. In contrast to the other CAL-A-type lipases, this hypothetical U. maydis lipase is annotated to possess a prolonged N-terminus of unknown function. Here, we show for the first time the recombinant expression of two versions of lipase UM03410: the full-length form (lipUMf) and an Nterminally truncated form (lipUMs). For comparison to the prototype, the expression of recombinant CAL-A in E. coli was investigated. Although both forms of lipase UM03410 could be expressed functionally in E. coli, the N-terminally truncated form (lipUMs) demonstrated significantly higher activities towards p-nitrophenyl esters. The functional expression of the N-terminally truncated lipase was further optimized by the appropriate choice of the E. coli strain, lowering the cultivation temperature to 20 °C and enrichment of the cultivation medium with glucose. Primary characteristics of the recombinant lipase are its pH optimum in the range of 6.5-7.0 and its temperature optimum at 55 °C. As is typical for lipases, lipUM03410 shows preference for long chain fatty acid esters with myristic acid ester (C14:0 ester) being the most preferred one.More importantly, lipUMs exhibits an inherent preference for C18:1Δ9 trans and C18:1Δ11 trans-fatty acid esters similar to CAL-A. Therefore, the short form of this U. maydis lipase is the only other currently known lipase with a distinct trans-fatty acid selectivity.
authors.affiliation: Institute of Biochemistry, Department of Biotechnology & Enzyme Catalysis, Ernst-Moritz-Arndt University of Greifswald, Felix-Hausdorff Str. 4, 17487 Greifswald, Germany.
authors.forename: Henrike
authors.initials: H
authors.lastname: Brundiek
authors.forename: Stefan
authors.initials: S
authors.lastname: Saß
authors.forename: Andrew
authors.initials: A
authors.lastname: Evitt
authors.forename: Robert
authors.initials: R
authors.lastname: Kourist
authors.forename: Uwe T
authors.initials: UT
authors.lastname: Bornscheuer
mesh_terms: D004795:Enzyme Stability; D005656:Fungal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008049:Lipase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010935:Plant Diseases / Q000382:microbiology*; D017434:Protein Structure, Tertiary; D013379:Substrate Specificity; D044242:Trans Fatty Acids / Q000737:chemistry / Q000378:metabolism*; D014588:Ustilago / Q000737:chemistry / Q000201:enzymology* / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D044242:Trans Fatty Acids; D008049:Lipase