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Omar MN, Rahman RNZRA, Noor NDM, Latip W, Knight VF, Ali MSM. Exploring the Antarctic aminopeptidase P from Pseudomonas sp. strain AMS3 through structural analysis and molecular dynamics simulation. J Biomol Struct Dyn 2024:1-13. [PMID: 38555730 DOI: 10.1080/07391102.2024.2331093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 03/11/2024] [Indexed: 04/02/2024]
Abstract
Aminopeptidase P (APPro) is a crucial metalloaminopeptidase involved in amino acid cleavage from peptide N-termini, playing essential roles as versatile biocatalysts with applications ranging from pharmaceuticals to industrial processes. Despite acknowledging its potential for catalysis in lower temperatures, detailed molecular basis and biotechnological implications in cold environments are yet to be explored. Therefore, this research aims to investigate the molecular mechanisms underlying the cold-adapted characteristics of APPro from Pseudomonas sp. strain AMS3 (AMS3-APPro) through a detailed analysis of its structure and dynamics. In this study, structure analysis and molecular dynamics (MD) simulation of a predicted model of AMS3-APPro has been performed at different temperatures to assess structural flexibility and thermostability across a temperature range of 0-60 °C over 100 ns. The MD simulation results revealed that the structure were able to remain stable at low temperatures. Increased temperatures present a potential threat to the overall stability of AMS3-APPro by disrupting the intricate hydrogen bond networks crucial for maintaining structural integrity, thereby increasing the likelihood of protein unfolding. While the metal binding site at the catalytic core exhibits resilience at higher temperatures, highlighting its local structural integrity, the overall enzyme structure undergoes fluctuations and potential denaturation. This extensive structural instability surpasses the localized stability observed at the metal binding site. Consequently, these assessments offer in-depth understanding of the cold-adapted characteristics of AMS3-APPro, highlighting its capability to uphold its native conformation and stability in low-temperature environments. In summary, this research provides valuable insights into the cold-adapted features of AMS3-APPro, suggesting its efficient operation in low thermal conditions, particularly relevant for potential biotechnological applications in cold environments.
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Affiliation(s)
- Muhamad Nadzmi Omar
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Raja Noor Zaliha Raja Abd Rahman
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Noor Dina Muhd Noor
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Wahhida Latip
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Victor Feizal Knight
- Research Centre for Chemical Defence, National Defence University of Malaysia, Kem Perdana Sungai Besi, Kuala Lumpur, Malaysia
| | - Mohd Shukuri Mohamad Ali
- Enzyme and Microbial Technology Research Centre, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
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Song P, Zhang X, Wang S, Xu W, Wang F, Fu R, Wei F. Microbial proteases and their applications. Front Microbiol 2023; 14:1236368. [PMID: 37779686 PMCID: PMC10537240 DOI: 10.3389/fmicb.2023.1236368] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 08/30/2023] [Indexed: 10/03/2023] Open
Abstract
Proteases (proteinases or peptidases) are a class of hydrolases that cleave peptide chains in proteins. Endopeptidases are a type of protease that hydrolyze the internal peptide bonds of proteins, forming shorter peptides; exopeptidases hydrolyze the terminal peptide bonds from the C-terminal or N-terminal, forming free amino acids. Microbial proteases are a popular instrument in many industrial applications. In this review, the classification, detection, identification, and sources of microbial proteases are systematically introduced, as well as their applications in food, detergents, waste treatment, and biotechnology processes in the industry fields. In addition, recent studies on techniques used to express heterologous microbial proteases are summarized to describe the process of studying proteases. Finally, future developmental trends for microbial proteases are discussed.
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Affiliation(s)
- Peng Song
- College of Life Sciences, Liaocheng University, Liaocheng, China
- Shandong Aobo Biotech Co. Ltd., Liaocheng, China
- Jiangxi Zymerck Biotech Co. Ltd., Nanchang, China
| | - Xue Zhang
- College of Life Sciences, Liaocheng University, Liaocheng, China
| | - Shuhua Wang
- Shandong Aobo Biotech Co. Ltd., Liaocheng, China
| | - Wei Xu
- College of Life Sciences, Liaocheng University, Liaocheng, China
| | - Fei Wang
- College of Life Sciences, Liaocheng University, Liaocheng, China
| | - Rongzhao Fu
- Jiangxi Zymerck Biotech Co. Ltd., Nanchang, China
| | - Feng Wei
- College of Life Sciences, Liaocheng University, Liaocheng, China
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3
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From bitter to delicious: properties and uses of microbial aminopeptidases. World J Microbiol Biotechnol 2023; 39:72. [PMID: 36625962 DOI: 10.1007/s11274-022-03501-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 12/14/2022] [Indexed: 01/11/2023]
Abstract
Protein hydrolysates are easily digested and utilized by humans and animals, and are less likely to cause allergies. Protein hydrolysis caused by endopeptidases often leads to the exposure of hydrophobic amino acids at the ends of peptides, which consequently causes bitter taste. Microbial aminopeptidases remove the exposed hydrophobic amino acids at the ends of aminopeptides, which improves taste, allowing for easier production. This processe is attacking significant attention from industry and laboratories. Aminopeptidases selectively hydrolyze peptide bonds from the N-terminal of proteins or peptides to produce free amino acids. Aminopeptidases can be classified into leucine, lysine, methionine and proline aminopeptidases by hydrolyzed N-terminal residues; metallo-, serine- and cysteine- aminopeptidases by the reaction mechanisms; dipeptide and triphoptide enzymes by the released number of amino acid residues at the end of hydrolyzed peptides; or acidic, neutral and basic aminopeptidases by their optimal hydrolysis pH. Commercial aminopeptidases are generally produced by microbial fermentation, and are mainly applied in the debittering of protein hydrolysates, the deep hydrolysis of protein, and the production of condiments, cheese, and bioactive peptides, as well as for disease detection in the medical industry.
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4
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Prolyl aminopeptidases: Reclassification, properties, production and industrial applications. Process Biochem 2022. [DOI: 10.1016/j.procbio.2022.04.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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5
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Song P, Feng W. Functional expression and characterization of a novel aminopeptidase B from Aspergillus niger in Pichia pastoris. 3 Biotech 2021; 11:366. [PMID: 34290949 DOI: 10.1007/s13205-021-02915-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/01/2021] [Indexed: 11/27/2022] Open
Abstract
A novel aminopeptidase B (APB-AN) was identified from Aspergillus niger CGMCC 3.1454 for the first time and was cloned and expressed in Pichia pastoris. The mature enzyme of approximately 100 kDa was purified for characterization. The optimum pH and temperature of the recombinant APB-AN were determined to be 7.0 and 40 °C, respectively. The enzyme was stable below 40 °C and at pH values from 5.0 to 8.0. The K m and V max values were determined to be 0.61 mmol/L and 11.45 mmol/L/min, respectively, using Arg-pNA as the substrate. APB-AN was inhibited by Cu2+ and Fe2+ and activated by Co2+ and Na+. Most metal chelators (Ca2+, Mg2+ and Mn2+) and aminopeptidase inhibitors (bestatin and puromycin) suppressed its activity. APB-AN was found to be active towards 13 kinds of amino acid p-nitroanilide (pNA) substrates:Arg-pNA, Lys-pNA, Tyr- pNA, Trp-pNA, Phe-pNA, His-pNA, Ala-pNA, Met-pNA, Leu-pNA, Glu-pNA, Val-pNA, Pro-pNA and Ile-pNA, and the most preferred N-terminal amino acids were arginine and lysine. APB-AN also hydrolyzed 4 natural proteins: casein, bovine serum albumin, soy protein isolate and water-soluble wheat protein. It is expected that APB-AN has potential food processing applications.
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Affiliation(s)
- Peng Song
- School of Life Sciences, Liaocheng University, Liaocheng, 252000 China
| | - Wei Feng
- School of Life Sciences, Liaocheng University, Liaocheng, 252000 China
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Liu D, Zhang D, Huang Q, Gu L, Zhou N, Tian Y. Mutagenesis for Improvement of Activity and Stability of Prolyl Aminopeptidase from Aspergillus oryzae. Appl Biochem Biotechnol 2020; 191:1483-1498. [PMID: 32125650 DOI: 10.1007/s12010-020-03277-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/13/2020] [Indexed: 11/27/2022]
Abstract
In this study, the prokaryotic expression system of Escherichia coli was used to modify prolyl aminopeptidase derived from Aspergillus oryzae JN-412 (AoPAP) via random mutagenesis and site-directed saturation mutagenesis. A random mutant library with a capacity of approximately 3000 mutants was compiled using error-prone polymerase chain reaction, and nonconservative amino acids within 3 Å of the substrate L-proline-p-nitroaniline were selected as site-directed saturation mutagenesis sites via homologous simulation and molecular docking of AoPAP. Variants featuring high catalytic efficiency were screened by a high-throughput screening method. The specific activities of the variants of 3D9, C185V, and Y393W were 127 U mg-1, 156 U mg-1, and 120 U mg-1, respectively, which were 27%, 56%, and 20% higher than those of the wild type, with a value of 100 U mg-1. The half-life of thermostability of the mutant 3D9 was 4.5 h longer than that of the wild type at 50 °C. The mutant C185V improved thermostability and had a half-life 2 h longer than that of the wild type at a pH of 6.5. Prolyl aminopeptidase had improved stability within the acidic range and thermostability after modification, making it more suitable for a synergistic combination with various acidic and neutral endoproteases.
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Affiliation(s)
- Dehua Liu
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Dawei Zhang
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Qinqin Huang
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Lili Gu
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Nandi Zhou
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
| | - Yaping Tian
- The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
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7
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Liu X, Zhang QY, Wang F, Jiang JH. A near infrared fluorescent probe for the detection and imaging of prolyl aminopeptidase activity in living cells. Analyst 2020; 144:5980-5985. [PMID: 31531498 DOI: 10.1039/c9an01303b] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Prolyl aminopeptidase (PAP) is an important exopeptidase which might be a biomarker for pathogen infection and a potential therapeutic target. However, very few fluorescent probes have been developed for detecting PAP activity. Here we report the development of the first near infrared (NIR) turn-on fluorescent probe (NIR-PAP) for detecting and imaging PAP in living cells. The probe is prepared by reacting a cysteine-proline dipeptide with an acryloylated NIR fluorophore via a facile thiol-Michael addition reaction. NIR-PAP exhibits a dynamic response toward PAP in the range of 0.02-2.5 U mL-1 with an estimated limit of detection of 0.013 U mL-1. In vitro studies also reveal that the probe displays high specificity and robust responses toward PAP under physiological pH and temperature conditions. Moreover, NIR-PAP is successfully introduced to detect and differentiate PAP activity in four different cell lines via both confocal fluorescence imaging and flow cytometry. Therefore, our probe may hold great promise in diagnosing infectious diseases caused by pathogens and screening therapeutic drugs in vivo.
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Affiliation(s)
- Xianjun Liu
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.
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Expression of Bacillus licheniformis α-amylase in Pichia pastoris without antibiotics-resistant gene and effects of glycosylation on the enzymic thermostability. 3 Biotech 2019; 9:427. [PMID: 31696032 DOI: 10.1007/s13205-019-1943-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 10/10/2019] [Indexed: 10/25/2022] Open
Abstract
Thermostable α-amylases are widely used in industry. The α-amylase from Bacillus licheniformis (BLA) with six potential glycosylation sites possessed excellent thermal and pH stability and high activity. Here, it was expressed in Pichia pastoris. The Pic-BLA-producing yeast without any antibiotics-resistant gene was cultivated in flasks and the amylase activity in fermentation supernatant reached 900 U/mL. The recombinant α-amylase Pic-BLA produced in P. pastoris was deeply glycosylated with 30% increase in molecular mass (MM). The deglycosylation treatment by Endoglycosidase H (Endo H) reduced the MM of Pic-BLA. Thermostability analysis showed that Pic-BLA and deglycosylated Pic-BLA were similar in heat tolerance. In order to eliminate the extra impact of Endo H, the BLA was also expressed in Escherichia coli to get non-glycosylated Eco-BLA. A comparative study between non-glycosylated Eco-BLA and glycosylated Pic-BLA showed no obvious difference in thermostability. It is speculated that the glycosylation has little effect on the thermostability of α-amylase BLA.
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Li T, Tian Y, Sun F, Wang Z, Zhou N. Preparation of high Fischer’s ratio corn oligopeptides using directed enzymatic hydrolysis combined with adsorption of aromatic amino acids for efficient liver injury repair. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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10
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Wang K, Tian Y, Zhou N, Liu D, Zhang D. Studies on fermentation optimization, stability and application of prolyl aminopeptidase from Bacillus subtilis. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.08.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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11
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Song XD, Liu CJ, Huang SH, Li XR, Yang E, Luo YY. Cloning, expression and characterization of two S-ribosylhomocysteine lyases from Lactobacillus plantarum YM-4-3: Implication of conserved and divergent roles in quorum sensing. Protein Expr Purif 2018; 145:32-38. [PMID: 29305177 DOI: 10.1016/j.pep.2017.12.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 11/03/2017] [Accepted: 12/27/2017] [Indexed: 12/31/2022]
Abstract
Quorum sensing (QS) is a means of cell-to-cell communication that regulates, via small signalling molecules, expression of a series of genes and controls multicellular behaviour in many bacterial species. The enzyme S-ribosylhomocysteine lyase (LuxS) transforms S-ribosylhomocysteine (SRH) into 4, 5-dihydroxy-2, 3-pentanedione (DPD), the precursor of the interspecies QS signalling molecule autoinducer-2 (AI-2). In this study, two LuxS-coding genes, luxS1 and luxS2, with 70% sequence identity were isolated from Lactobacillus plantarum YM-4-3, and overexpressed in Escherichia coli BL21 (DE3), and the protein products were purified successfully. After incubation of LuxS1 or LuxS2 with SRH, the reaction products were able to induce Vibrio harveyi BB170 bioluminescence, clearly demonstrating that both LuxS1 and LuxS2 synthesize AI-2 from SRH in vitro. Ellman's assay results revealed optimal temperatures for LuxS1 and LuxS2 of 45 and 37 °C, respectively, and their activities were stimulated or inhibited by several metal ions and chemical reagents. In addition, enzyme kinetics data showed that Km, Vmax and Kcat value of LuxS1 for the substrate (SRH) were higher than that of LuxS2. These results suggest that LuxS1 and LuxS2 mediate QS in a temperature-dependent manner and may play conserved roles in AI-2 synthesis but exhibit different activities in response to external environmental stress. To our knowledge, this paper is the first report of two luxS genes present in one bacterial genome and the subsequent comparative elucidation of their functions in AI-2 production. Collectively, our study provides a solid basis for future research concerning the AI-2/LuxS QS system in L. plantarum YM-4-3.
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Affiliation(s)
- Xiao-Dong Song
- Laboratory of Applied Microbiology, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, PR China
| | - Chen-Jian Liu
- Laboratory of Applied Microbiology, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, PR China
| | - Shi-Hao Huang
- Laboratory of Applied Microbiology, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, PR China
| | - Xiao-Ran Li
- Laboratory of Applied Microbiology, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, PR China
| | - En Yang
- Laboratory of Applied Microbiology, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, PR China
| | - Yi-Yong Luo
- Laboratory of Applied Microbiology, Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, 650500, PR China.
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Engineering strategies for enhanced production of protein and bio-products in Pichia pastoris: A review. Biotechnol Adv 2017; 36:182-195. [PMID: 29129652 DOI: 10.1016/j.biotechadv.2017.11.002] [Citation(s) in RCA: 243] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 10/16/2017] [Accepted: 11/06/2017] [Indexed: 11/24/2022]
Abstract
Pichia pastoris has been recognized as one of the most industrially important hosts for heterologous protein production. Despite its high protein productivity, the optimization of P. pastoris cultivation is still imperative due to strain- and product-specific challenges such as promoter strength, methanol utilization type and oxygen demand. To address the issues, strategies involving genetic and process engineering have been employed. Optimization of codon usage and gene dosage, as well as engineering of promoters, protein secretion pathways and methanol metabolic pathways have proved beneficial to innate protein expression levels. Large-scale production of proteins via high cell density fermentation additionally relies on the optimization of process parameters including methanol feed rate, induction temperature and specific growth rate. Recent progress related to the enhanced production of proteins in P. pastoris via various genetic engineering and cultivation strategies are reviewed. Insight into the regulation of the P. pastoris alcohol oxidase 1 (AOX1) promoter and the development of methanol-free systems are highlighted. Novel cultivation strategies such as mixed substrate feeding are discussed. Recent advances regarding substrate and product monitoring techniques are also summarized. Application of P. pastoris to the production of biodiesel and other value-added products via metabolic engineering are also reviewed. P. pastoris is becoming an indispensable platform through the use of these combined engineering strategies.
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13
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Yu Y, Liu Z, Yang M, Chen M, Wei Z, Shi L, Li L, Mou H. Characterization of Full-Length and Truncated Recombinant κ-Carrageenase Expressed in Pichia pastoris. Front Microbiol 2017; 8:1544. [PMID: 28861059 PMCID: PMC5561669 DOI: 10.3389/fmicb.2017.01544] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 07/31/2017] [Indexed: 11/13/2022] Open
Abstract
κ-Carrageenase belongs to glycoside hydrolase family 16 and cleaves the β-(1→4) linkages of κ-carrageenan. In this study, genes encoding the full-length (cgkZ), Por secretion tail-truncated (cgkZΔPst) and carbohydrate binding domain-truncated (cgkZΔCBM) κ-carrageenase proteins were expressed in Pichia pastoris. The copy numbers of gene cgkZ, cgkZΔPst and cgkZΔCBM were 7, 7 and 6, respectively. The enzymatic activities of recombinant enzymes cgkZ, cgkZΔPst and cgkZΔCBM reached 4.68, 5.70, and 3.02 U/mL, respectively, after 120 h of shake flask fermentation at 22°C and pH 6 in the presence of 1 % (v/v) methanol. The molecular weights of recombinant cgkZ, cgkZΔPst, and cgkZΔCBM were approximately 65, 45, and 40 kDa; their Km values were 2.07, 1.85, and 1.04 mg/mL; and they exhibited optimal activity at 45-50°C and pH 6-7. All the recombinant enzymes were stimulated by Na+, Mg2+, Ca2+, and dithiothreitol. The end-products of enzymatic hydrolysis were mainly composed of κ-carrageenan tetrasaccharide and hexasaccharide. The removal of the Por secretion tail of κ-carrageenase promoted the transcription of κ-carrageenase gene, enhancing the specific activity of κ-carrageenase without significantly changing its catalytic properties. Although the transcription level of κ-carrageenase gene after the removal of the carbohydrate binding domain was relatively high, the specific activity of the recombinant enzyme significantly decreased. The comprehensive application of the P. pastoris expression system combined with the rational modification of genes may provide a novel approach for the heterologous expression of various marine enzymes with high activities.
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Affiliation(s)
- Yuan Yu
- College of Food Science and Engineering, Ocean University of ChinaQingdao, China
| | - Zhemin Liu
- College of Food Science and Engineering, Ocean University of ChinaQingdao, China
| | - Min Yang
- College of Food Science and Engineering, Ocean University of ChinaQingdao, China
| | - Meng Chen
- College of Food Science and Engineering, Ocean University of ChinaQingdao, China
| | - Zhihan Wei
- College of Food Science and Engineering, Ocean University of ChinaQingdao, China
| | - Lixia Shi
- College of Food Science and Engineering, Ocean University of ChinaQingdao, China
| | - Li Li
- College of Food Science and Engineering, Ocean University of ChinaQingdao, China
| | - Haijin Mou
- College of Food Science and Engineering, Ocean University of ChinaQingdao, China
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