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Ma L, Ma Q, Cai R, Zong Z, Du L, Guo G, Zhang Y, Xiao D. Effect of β-mannanase domain from Trichoderma reesei on its biochemical characters and synergistic hydrolysis of sugarcane bagasse. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2018; 98:2540-2547. [PMID: 29028116 DOI: 10.1002/jsfa.8741] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 10/09/2017] [Accepted: 10/10/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND β-mannanase is a key enzyme for hydrolyzing mannan, a major constituent of hemicellulose, which is the second most abundant polysaccharide in nature. Different structural domains greatly affect its biochemical characters and catalytic efficiency. However, the effects of linker and carbohydrate-binding module (CBM) on β-mannanase from Trichoderma reesei (Man1) have not yet been fully described. The present study aimed to determine the influence of different domains on the expression efficiency, biochemical characteristics and hemicellulosic deconstruction of Man1. RESULTS The expression efficiency was improved after truncating CBM. Activities of Man1 and Man1ΔCBM (CBM) in the culture supernatant after 168 h of induction were 34.5 and 42.9 IU mL-1 , although a value of only 0.36 IU mL-1 was detected for Man1ΔLCBM (lacking CBM and linker). Man1 showed higher thermostability than Man1ΔCBM at low temperature, whereas Man1ΔCBM had a higher specificity for galactomannan (Km = 2.5 mg mL-1 ) than Man1 (Km = 4.0 mg mL-1 ). Both Man1 and Man1ΔCBM could synergistically improve the hydrolysis of cellulose, galactomannan and pretreated sugarcane bagasse, with a 10-30% improvement of the reducing sugar yield. CONCLUSION Linker and CBM domains were vital for mannanase activity and expression efficiency. CBM affected the thermostability and adsorption ability of Man1. The results obtained in the present study should help guide the rational design and directional modification of Man with respect to improving its catalytic efficiency. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Lijuan Ma
- Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Qing Ma
- Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Rui Cai
- Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Zhiyou Zong
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, China
| | - Liping Du
- Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Gaojie Guo
- Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Yingying Zhang
- Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Dongguang Xiao
- Key Laboratory of Industrial Microbiology, Ministry of Education, Tianjin Industrial Microbiology Key Laboratory, College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
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Wang Q, Chen CH, Chung CY, Priola J, Chu JH, Tang J, Ulmschneider MB, Betenbaugh MJ. Proline-Rich Chaperones Are Compared Computationally and Experimentally for Their Abilities to Facilitate Recombinant Butyrylcholinesterase Tetramerization in CHO Cells. Biotechnol J 2017; 13:e1700479. [DOI: 10.1002/biot.201700479] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 09/26/2017] [Indexed: 11/12/2022]
Affiliation(s)
- Qiong Wang
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University; 221 Maryland Hall, 3400 N. Charles St. Baltimore Maryland 21218 USA
| | - Charles H. Chen
- Department of Materials Science and Engineering, Johns Hopkins University; 204C Shaffer Hall, 3400 N. Charles St. Baltimore Maryland 21218 USA
- Department of Chemistry, King's College London; Britannia House, 7 Trinity Street London SE1 1DB UK
| | - Cheng-yu Chung
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University; 221 Maryland Hall, 3400 N. Charles St. Baltimore Maryland 21218 USA
| | - Joseph Priola
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University; 221 Maryland Hall, 3400 N. Charles St. Baltimore Maryland 21218 USA
| | - Jeffrey H. Chu
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University; 221 Maryland Hall, 3400 N. Charles St. Baltimore Maryland 21218 USA
| | - Juechun Tang
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University; 221 Maryland Hall, 3400 N. Charles St. Baltimore Maryland 21218 USA
| | - Martin B. Ulmschneider
- Department of Materials Science and Engineering, Johns Hopkins University; 204C Shaffer Hall, 3400 N. Charles St. Baltimore Maryland 21218 USA
- Department of Chemistry, King's College London; Britannia House, 7 Trinity Street London SE1 1DB UK
| | - Michael J. Betenbaugh
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University; 221 Maryland Hall, 3400 N. Charles St. Baltimore Maryland 21218 USA
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Microfluidic droplet platform for ultrahigh-throughput single-cell screening of biodiversity. Proc Natl Acad Sci U S A 2017; 114:2550-2555. [PMID: 28202731 DOI: 10.1073/pnas.1621226114] [Citation(s) in RCA: 144] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Ultrahigh-throughput screening (uHTS) techniques can identify unique functionality from millions of variants. To mimic the natural selection mechanisms that occur by compartmentalization in vivo, we developed a technique based on single-cell encapsulation in droplets of a monodisperse microfluidic double water-in-oil-in-water emulsion (MDE). Biocompatible MDE enables in-droplet cultivation of different living species. The combination of droplet-generating machinery with FACS followed by next-generation sequencing and liquid chromatography-mass spectrometry analysis of the secretomes of encapsulated organisms yielded detailed genotype/phenotype descriptions. This platform was probed with uHTS for biocatalysts anchored to yeast with enrichment close to the theoretically calculated limit and cell-to-cell interactions. MDE-FACS allowed the identification of human butyrylcholinesterase mutants that undergo self-reactivation after inhibition by the organophosphorus agent paraoxon. The versatility of the platform allowed the identification of bacteria, including slow-growing oral microbiota species that suppress the growth of a common pathogen, Staphylococcus aureus, and predicted which genera were associated with inhibitory activity.
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Dwyer M, Javor S, Ryan DA, Smith EM, Wang B, Zhang J, Cashman JR. Novel human butyrylcholinesterase variants: toward organophosphonate detoxication. Biochemistry 2014; 53:4476-87. [PMID: 24902043 PMCID: PMC4100784 DOI: 10.1021/bi500491w] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Human
butyrylcholinesterase (hBChE) is currently being developed
as a detoxication enzyme for stoichiometric binding and/or catalytic
hydrolysis of organophosphates. Herein, we describe the use of a molecular
evolution method to develop novel hBChE variants with increased resistance
to stereochemically defined nerve agent model compounds of soman,
sarin, and cyclosarin. Novel hBChE variants (Y332S, D340H, and Y332S/D340H)
were identified with an increased resistance to nerve agent model
compounds that retained robust intrinsic catalytic efficiency. Molecular
dynamics simulations of these variants revealed insights into the
mechanism by which these structural changes conferred nerve agent
model compound resistance.
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Affiliation(s)
- Mary Dwyer
- Human BioMolecular Research Institute , 5310 Eastgate Mall, San Diego, California 92121, United States
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Truncation of N-terminal regions of Digitalis lanata progesterone 5β-reductase alters catalytic efficiency and substrate preference. Biochimie 2013; 101:31-8. [PMID: 24370479 DOI: 10.1016/j.biochi.2013.12.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 12/12/2013] [Indexed: 02/03/2023]
Abstract
N-Terminal truncated forms of progesterone 5β-reductase (P5βR) were synthesized taking a full-length cDNA encoding for Digitalis lanata P5βR with a hexa-histidine tag attached at the C-terminus (rDlP5βRc) as the starting point. Four pETite-c-His/DlP5βR constructs coding for P5βR derivatives truncated in the N-terminal region, termed rDlP5βRcn-10, rDlP5βRcn-20, rDlP5βRcn-30, and rDlP5βRcn-40 were obtained by site-directed mutagenesis. The cDNAs coding for full-length rDlP5βRc, rDlP5βRcn-10 and rDlP5βRcn-20 were over-expressed in Escherichia coli and the respective enzymes were soluble and catalytically active (progesterone and 2-cyclohexen-1-one as substrates). GST-tagged recombinant DlP5βR (rDlP5βR-GST) and rDlP5βR-GSTr, with the GST-tag removed by protease treatment were produced as well and served as controls. The Km values and substrate preferences considerably differed between the various DlP5βR derivatives. As for the C-terminal His-tagged rDlP5βR the catalytic efficiency for progesterone was highest for the full-length rDlP5βRc whereas the N-terminal truncated forms preferred 2-cyclohexen-1-one as the substrate. Affinity tags and artifacts resulting from the cloning strategy used may alter substrate specificity. Therefore enzyme properties determined with recombinant proteins should not be used to infer in vivo scenarios and should be considered for each particular case.
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Zhang J, Chen S, Ralph EC, Dwyer M, Cashman JR. Identification of human butyrylcholinesterase organophosphate-resistant variants through a novel mammalian enzyme functional screen. J Pharmacol Exp Ther 2012; 343:673-82. [PMID: 22956723 DOI: 10.1124/jpet.112.198499] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Human butyrylcholinesterase (hBChE) is currently being developed as a detoxication enzyme for the catalytic hydrolysis or stoichiometric binding of organophosphates (OPs). Previously, rationally designed hBChE mutants (G117H and E197Q) were reported in the literature and showed the feasibility of engineering OP hydrolytic functional activity into hBChE. However, the OP hydrolysis rate for G117H is too low for clinical utility. Additional OP-resistant hBChE variants with greater hydrolysis rates are needed as OP nerve-agent countermeasures for therapeutic utility. As described herein, a directed molecular evolution process was used to identify amino acid residues that contribute to OP-resistant functional activity of hBChE variants. In this article, we describe the development and validation of a novel method to identify hBChE variants with OP-resistant functional activity (decreased rate of OP inhibition). The method reported herein used an adenoviral protein expression system combined with a functional screening protocol of OP nerve-agent model compounds that have been shown to have functional properties similar to authentic OP nerve-agent compounds. The hBChE screening method was robust for transfection efficiency, library diversity, and reproducibility of positive signals. The screening approach not only identified the previously reported hBChE G117H variant, but also identified a series of additional hBChE variants, including hBChE G117N, G117R, E197C, and L125V, that exhibited OP-resistant functional activities not reported previously. The mammalian functional screening approach can serve as a cornerstone for further optimization and screening for OP-resistant hBChEs for potential therapeutic applications.
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Affiliation(s)
- Jun Zhang
- Human BioMolecular Research Institute, San Diego, CA 92121, USA
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Kalisiak J, Ralph EC, Cashman JR. Nonquaternary reactivators for organophosphate-inhibited cholinesterases. J Med Chem 2011; 55:465-74. [PMID: 22206546 DOI: 10.1021/jm201364d] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new class of amidine-oxime reactivators of organophosphate (OP)-inhibited cholinesterases (ChE) was synthesized and tested in vitro and in vivo. Compared with 2-PAM, the most promising cyclic amidine-oxime (i.e., 12e) showed comparable or greater reactivation of OP-inactivated AChE and OP-inactivated BChE. To the best of our knowledge, this is the first report of a nonquaternary oxime that has, comparable to 2-PAM, in vitro potency for reactivation of Sarin (GB)-inhibited AChE and BChE. Amidine-oximes were tested in vitro, and reactivation rates for OP-inactivated butyrylcholinesterase (BChE) were greater than those for 2-PAM or MINA. Amidine-oxime reactivation rates for OP-inactivated acetylcholinesterase (AChE) were lower compared to 2-PAM but greater compared with MINA. Amidine-oximes were tested in vivo for protection against the toxicity of nerve agent model compounds. (i.e., a model of Sarin). Post-treatment (i.e., 5 min after OP exposure, i.p,) with amidine oximes 7a-c and 12a, 12c, 12e, 12f, and 15b (145 μmol/kg, i.p.) protected 100% of the mice challenged with the sarin model compound. Even at 25% of the initial dose of amidine-oxime (i.e., a dose of 36 μmol/kg, i.p.), 7b and 12e protected 100% of the animals challenged with the sarin nerve agent model compound that caused lethality in 6/11 animals without amidine-oxime.
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Affiliation(s)
- Jarosław Kalisiak
- Human BioMolecular Research Institute, 5310 Eastgate Mall, San Diego, California 92121, United States
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