Family 3 CBM improves the biochemical properties, substrate hydrolysis and coconut oil extraction by hemicellulolytic and holocellulolytic chimeras.

Autor: Monica P; Department of Microbiology and Fermentation Technology, CSIR-Central Food Technological Research Institute, Mysuru 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, UP, India., Ranjan R; Department of Microbiology and Fermentation Technology, CSIR-Central Food Technological Research Institute, Mysuru 570 020, India., Kapoor M; Department of Microbiology and Fermentation Technology, CSIR-Central Food Technological Research Institute, Mysuru 570 020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, UP, India. Electronic address: mkapoor@cftri.res.in.
Jazyk: angličtina
Zdroj: Enzyme and microbial technology [Enzyme Microb Technol] 2024 Mar; Vol. 174, pp. 110375. Date of Electronic Publication: 2023 Dec 12.
DOI: 10.1016/j.enzmictec.2023.110375
Abstrakt: To understand the influence of family 3 Carbohydrate Binding Module (hereafter CBM3), single (GH5 cellulase; CelB, CelBΔCBM), bi-chimeric [GH26 endo-mannanase (ManB-1601) and GH11 endo-xylanase (XynB); ManB-XynB [1], ManB-XynB-CBM] and tri-chimeric [ManB-XynB-CelB [1], ManB-XynB-CelBΔCBM] enzyme variants (fused or deleted of CBM) were produced and purified to homogeneity. CBM3 did not alter the pH and temperature optima of bi- and tri-chimeric enzymes but improved the pH and temperature stability of ManB in CBM variants of bi-/tri-chimeric enzymes. Truncation of CBM in CelB shifted the pH optimum and increased the melting temperature (T m 65 ℃). CBM3 improved both substrate affinity (K m ) and catalytic efficiency (k cat /K m ) of fused enzymes in tri-chimera and CelB but only K m for bi-chimera. Far-UV CD of CelB and bi- and tri-chimeric enzymes suggested that CBM3 improved the α-helical content and compactness in the native state but did not prevent disintegration of secondary structural contents at acidic pH. Steady-state fluorescence studies suggested that under acidic conditions CBM3 prevented the exposure of hydrophobic patches in bi-chimeric protein but could not avert the opening up of chimeric enzyme structure. Aqueous enzyme assisted treatment of mature coconut kernel using single, bi- and tri-chimeric enzymes led to cracks, peeling and fracturing of the matrix and improved the oil yield by up to 22%.
Competing Interests: Declaration of Competing Interest The authors have no competing interests to declare that are relevant to the content of this article.
(Copyright © 2023 Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
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