N-α-acylation of lysine catalyzed by immobilized aminoacylases from Streptomyces ambofaciens in aqueous medium

• Published in: Microporous and mesoporous materials Vol. 267; pp. 24 - 34
• Main Authors: Dettori, L., Vibert, F., Guiavarc'h, Y., Delaunay, S., Humeau, C., Blin, J.L., Chevalot, I.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.09.2018; Elsevier
• Subjects: Aminoacylases; Chemical and Process Engineering; Engineering Sciences; Immobilization; Mesoporous silica; N-acylation; SBA-15; Immobilization; N-acylation; SBA-15; Aminoacylases; Mesoporous silica
• ISSN: 1387-1811; 1873-3093
• DOI: 10.1016/j.micromeso.2018.03.018

Aminoacylases (EC 3.5.1.1.4) of Streptomyces ambofaciens ATCC 23877 were immobilized by chemical and physical adsorption onto SBA-15 mesoporous silica materials. The activity of the immobilized aminoacylases was firstly evaluated by considering the hydrolysis reactions of N-α-acetyl-lysine, used as rapid method of screening. After chemical adsorption, a significant loss of activity was observed probably due to a conformational change of the aminoacylases structures upon immobilization. When the immobilization was performed by physisorption a higher amount of enzyme (0.20 against 0.05 mg per mg of support) can be adsorbed onto the mesoporous silica material. The physisorbed biocatalyst also presented a higher hydrolytic activity than the chemisorbed enzyme. Recycling of the supported biocatalysts was performed three times with no loss of the specific activity. Furthermore, a better thermostability was also noted in comparison with free enzyme upon aminoacylases physisorption. Finally, lauroyl-lysine synthesis was catalyzed for the first time by immobilized aminoacylases. The crude extract from S. ambofaciens exhibited the rare ability to catalyze the N-acylation on amino group in the α-position of the lysine whereas the lipase B of Candida antarctica catalyzed the acylation of lysine on its amino group in ε-position. This particular and original regioselectivity was maintained with immobilized enzymes. [Display omitted] •Regioselectivity of both free and immobilized amino-acylases towards hydrolysis of α-acetyl-lysine.•Higher amount of amino-acylases immobilized by physisorption than by chemisorption.•Thermal stability of amino-acylases enhanced after physisorption.•Specific activity of amino-acylases maintained upon immobilization at least during 3 cycles.•Original α-lauroyl-lysine synthesis by immobilized amino-acylases.