| Title : Function of C-terminal peptides on enzymatic and interfacial adsorption properties of lipase from Gibberella zeae - Wang_2018_Biochim.Biophys.Acta.Gen.Subj_1862_2623 |
| Author(s) : Wang F , Zhang H , Czarna A , Chen W , Yang B , Wang Y |
| Ref : Biochimica & Biophysica Acta Gen Subj , 1862 :2623 , 2018 |
| Abstract : BACKGROUND: The crystal structure of lipase from Gibberella zeae (GZEL) indicates that its C-terminal extension is composed of a loop and a alpha-helix. This structure is unique, possibly providing novel evidence on lipase mechanisms. METHODS: Two C-terminally truncated mutants (GZEL-Delta(alpha-helix) and GZEL-Delta(alpha-helix+loop)) were constructed. The role of these secondary structure segments on enzymatic activities and interfacial binding properties of GZEL was investigated by using conventional pH-stat method and monomolecular film techniques. In addition, inactive variants (Ser144Ala) of wild-type GZEL and two truncated mutants were constructed and produced specifically for interfacial binding experiments. RESULTS: Compared to the wild-type GZEL, lipase and phospholipase activities were significantly decreased in the two mutants. Deletion of the alpha-helix had great influence on the lipase activity of GZEL, resulting in residual 7.3% activity; the additional deletion of the loop led to 8.1% lipase activity. As for the phospholipase function, residual activities of 63.0% and 35.4% were maintained for GZEL-Delta(alpha-helix) and GZEL-Delta(alpha-helix+loop), respectively. Findings obtained with monomolecular film experiments further indicated that the reduction in phospholipase activity occurred with the anionic phospholipid as substrate, but was not seen with zwitterionic phospholipid. Results of the maximum insertion pressure, synergy factor and binding kinetic parameters documented that the alpha-helix structure of GZEL strongly influence the binding and insertion of enzyme to the phospholipid monolayer. Moreover, the interfacial binding function of alpha-helix was partly conformed by connecting to the C-terminal of Aspergillus oryzae lipase. GENERAL SIGNIFICANCE: Our results provide important information on the understanding of the structure-function relationship of GZEL. |
| ESTHER : Wang_2018_Biochim.Biophys.Acta.Gen.Subj_1862_2623 |
| PubMedSearch : Wang_2018_Biochim.Biophys.Acta.Gen.Subj_1862_2623 |
| PubMedID: 30025859 |
Wang F, Zhang H, Czarna A, Chen W, Yang B, Wang Y (2018)
Function of C-terminal peptides on enzymatic and interfacial adsorption properties of lipase from Gibberella zeae
Biochimica & Biophysica Acta Gen Subj
1862 :2623
Wang F, Zhang H, Czarna A, Chen W, Yang B, Wang Y (2018)
Biochimica & Biophysica Acta Gen Subj
1862 :2623