1
|
Prabmark K, Boonyapakron K, Bunterngsook B, Arunrattanamook N, Uengwetwanit T, Chitnumsub P, Champreda V. Enhancement of catalytic activity and alkaline stability of cellobiohydrolase by structure-based protein engineering. 3 Biotech 2022; 12:269. [PMID: 36097631 PMCID: PMC9463429 DOI: 10.1007/s13205-022-03339-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 08/16/2022] [Indexed: 11/30/2022] Open
Abstract
Alkaline cellobiohydrolases have the potential for application in various industries, including pulp processing and laundry where operation under high pH conditions is preferred. In this study, variants of CtCel6A cellobiohydrolase from Chaetomium thermophilum were generated by structural-based protein engineering with the rationale of increasing catalytic activity and alkaline stability. The variants included removal of the carbohydrate-binding module (CBM) and substitution of residues 173 and 200. The CBM-deleted enzyme with Y200F mutation predicted to mediate conformational change at the N-terminal loop demonstrated increased alkaline stability at 60 °C, pH 8.0 for 24 h up to 2.25-fold compared with the wild-type enzyme. Another CBM-deleted enzyme with L173E mutation predicted to induce a new hydrogen bond in the substrate-binding cleft showed enhanced hydrolysis yield of pretreated sugarcane trash up to 4.65-fold greater than that of the wild-type enzyme at the pH 8.0. The variant enzymes could thus be developed for applications on cellulose hydrolysis and plant fiber modification operated under alkaline conditions. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-022-03339-4.
Collapse
Affiliation(s)
- Kanoknart Prabmark
- Enzyme Technology Research Team, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathum Thani, 12120 Thailand
| | - Katewadee Boonyapakron
- Enzyme Technology Research Team, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathum Thani, 12120 Thailand
| | - Benjarat Bunterngsook
- Enzyme Technology Research Team, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathum Thani, 12120 Thailand
| | - Nattapol Arunrattanamook
- Enzyme Technology Research Team, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathum Thani, 12120 Thailand
| | - Tanaporn Uengwetwanit
- Microarray Research Team, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathum Thani, 12120 Thailand
| | - Penchit Chitnumsub
- Biomolecular Analysis and Application Research Team, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathum Thani, 12120 Thailand
| | - Verawat Champreda
- Enzyme Technology Research Team, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathum Thani, 12120 Thailand
| |
Collapse
|
2
|
Identification of a novel family of carbohydrate-binding modules with broad ligand specificity. Sci Rep 2016; 6:19392. [PMID: 26765840 PMCID: PMC4725902 DOI: 10.1038/srep19392] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 11/03/2015] [Indexed: 11/13/2022] Open
Abstract
Most enzymes that act on carbohydrates include non-catalytic carbohydrate-binding modules (CBMs) that recognize and target carbohydrates. CBMs bring their appended catalytic modules into close proximity with the target substrate and increase the hydrolytic rate of enzymes acting on insoluble substrates. We previously identified a novel CBM (CBMC5614-1) at the C-terminus of endoglucanase C5614-1 from an uncultured microorganism present in buffalo rumen. In the present study, that the functional region of CBMC5614-1 involved in ligand binding was localized to 134 amino acids. Two representative homologs of CBMC5614-1, sharing the same ligand binding profile, targeted a range of β-linked polysaccharides that adopt very different conformations. Targeted substrates included soluble and insoluble cellulose, β-1,3/1,4-mixed linked glucans, xylan, and mannan. Mutagenesis revealed that three conserved aromatic residues (Trp-380, Tyr-411, and Trp-423) play an important role in ligand recognition and targeting. These results suggest that CBMC5614-1 and its homologs form a novel CBM family (CBM72) with a broad ligand-binding specificity. CBM72 members can provide new insight into CBM-ligand interactions and may have potential in protein engineering and biocatalysis.
Collapse
|
3
|
C-terminal flanking peptide stabilized the catalytic domain of a recombinant Bacillus subtilis endo-β-1, 4-glucanase. Protein J 2013; 32:246-52. [PMID: 23543074 DOI: 10.1007/s10930-013-9483-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Three proteins, Egl330, Egl326 and Egl325, which covered the catalytic domain of a Bacillus subtilis endo-β-l, 4-glucanase were expressed in Escherichia coli and purified. Egl325 was a mutant of Egl330 with the peptide sequence Arg-Glu-Asn-Ile-Arg deleted in the C-terminus and Egl326 was another mutant of Egl330 with the peptide sequence Glu-Asn-Ile-Arg deleted in the C-terminus. These three proteins displayed same optimal reaction pH and temperature. However, the thermal stability and pH stability of Egl326 and Egl325 were diminished compared to Egl330. Results of ultra violet scanning, circular dichroism and Trp fluorescence spectrometry showed that the absence of the short peptide at the C-terminus of Egl330 resulted in the destabilization of the catalytic domain through affecting the folding of the protein.
Collapse
|
4
|
Novel carbohydrate-binding module identified in a ruminal metagenomic endoglucanase. Appl Environ Microbiol 2010; 76:4867-70. [PMID: 20472722 DOI: 10.1128/aem.00011-10] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Endoglucanase C5614-1 comprises a catalytic module (CM) and an X module (XM). The XM showed no significant homology with known carbohydrate-binding modules (CBMs). Recombinant full-length endoglucanase could bind Avicel, whereas the CM could not. The XM could bind various polysaccharides. The results demonstrated that the XM was a new CBM.
Collapse
|