he changing face of SDS denaturation: Complexes of Thermomyces lanuginosus lipase with SDS at pH 4.0, 6.0 and 8.

Author(s)

Rasmussen, Helena Ostergaard ^{[1, 2]} ; Wollenberg, Daniel T. Weltz ^{[3, 4]} ; Wang, Huabing ^{[1, 5]} ; Andersen, Kell K. ^{[1, 6]} ; Oliveira, Cristiano L. P. ^{[1, 2, 7]} ; Jorgensen, Christian Isak ^[4] ; Jorgensen, Thomas J. D. ^[3] ; Otzen, Daniel E. ^{[1, 6]} ; Pedersen, Jan Skov ^{[1, 2]}

Affiliation

^[1] Aarhus Univ, Interdisciplinary Nanosci Ctr iNANO, Gustav Wieds Vej 14, DK-8000 Aarhus C - Denmark

^[2] Aarhus Univ, Dept Chem, Gustav Wieds Vej 14, DK-8000 Aarhus C - Denmark

^[3] Univ Southern Denmark, Dept Biochem & Mol Biol, Campusvej 55, DK-5230 Odense M - Denmark

^[4] Novozymes AS, Krogshojvej 36, DK-2880 Bagsvaerd - Denmark

^[5] Guangxi Med Univ, Guangxi Key Lab Enhanced Recovery Surg Gastrointe, Clin Lab Ctr, Affiliated Hosp 1, Shuangyong Rd 6, Nanning 530021, Guangxi Zhuang - Peoples R China

^[6] Aarhus Univ, Dept Mol Biol & Genet, Gustav Wieds Vej 10C, DK-8000 Aarhus C - Denmark

^[7] Univ Sao Paulo, Inst Phys, Complex Fluids Grp, Rua Matao 1371, Butanta, SP - Brazil

• Document type: Journal article
• Source: Journal of Colloid and Interface Science; v. 614, p. 214-232, MAY 15 2022.
• Web of Science Citations: 0

Abstract

Hypothesis: Lipases are widely used in the detergent industry and must withstand harsh conditions involving both anionic and zwitterionic surfactants at alkaline pH. Thermomyces lanuginosus lipase (TlL) is often used and stays active at high concentrations of the anionic surfactant sodium dodecyl sulfate (SDS) at pH 8.0, but is sensitive to SDS at pH 6.0 and below. We propose that enhanced stability at pH 8.0 results from a structurally distinct complex formation with SDS. Experiments: We use small-angle X-ray scattering (SAXS) to elucidate structures of TlL:SDS at pH 4.0, 6.0, and 8.0 and further investigate the complexes at pH 8.0 using hydrogen/deuterium exchange mass spec-trometry (HDX-MS). Findings: At pH 4.0, large dense aggregates are formed at low {[}SDS], which become gradually less dense at higher {[}SDS], resulting in a core-shell structure. At pH 6.0, SDS induces a TlL dimer and forms a hemimicelle along the side of the dimer. At higher {[}SDS], TlL adopts a core-shell structure. At pH 8.0, TlL forms a dimer with a SDS hemi-micelle but avoids a core-shell structure and maintains activity. Three helices are identified as SDS anchor points. This study provides important structural insight into the stability of TlL towards SDS under alkaline conditions. (c) 2022 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/). (AU)

• FAPESP's process: 18/16092-5 - Investigating colloidal systems by scattering methods
• Grantee: Cristiano Luis Pinto de Oliveira
• Support Opportunities: Regular Research Grants