1
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Joe GH, Masuoka M, Reisen R, Tanaka S, Saeki H. Development of a Sequential Fractionation-and-Recovery Method for Multiple Anti-Inflammatory Components Contained in the Dried Red Alga Dulse ( Palmaria palmata). Mar Drugs 2023; 21:md21050276. [PMID: 37233470 DOI: 10.3390/md21050276] [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: 03/06/2023] [Revised: 04/17/2023] [Accepted: 04/24/2023] [Indexed: 05/27/2023] Open
Abstract
A separation process was established to sequentially fractionate and recover three anti-inflammatory components derived from sugars, phycobiliprotein, and chlorophyll from the hot-air-dried thalli of the red alga dulse (Palmaria palmata). The developed process consisted of three steps, without the use of organic solvents. In Step I, the sugars were separated by disrupting the cell wall of the dried thalli with a polysaccharide-degrading enzyme, and a sugar-rich extract (E1) was obtained by precipitating the other components, which were simultaneously eluted by acid precipitation. In Step II, the residue suspension from Step I was digested with thermolysin to obtain phycobiliprotein-derived peptides (PPs), and a PP-rich extract (E2) was obtained by separating the other extracts using acid precipitation. In Step III, solubilized chlorophyll was obtained by heating the residue, which was acid-precipitated, neutralized, and re-dissolved to concentrate the chlorophyll-related components (Chls)-rich extract (E3). These three extracts suppressed inflammatory-cytokine secretion by lipopolysaccharide (LPS)-stimulated macrophages, confirming that the sequential procedure had no negative effects on the activities of any of the extracts. The E1, E2, and E3 were rich in sugars, PPs, and Chls, respectively, indicating that the anti-inflammatory components were effectively fractionated and recovered through the separation protocol.
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Affiliation(s)
- Ga-Hyun Joe
- Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan
| | - Masafumi Masuoka
- Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan
| | - Ryosuke Reisen
- Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan
| | - Seiya Tanaka
- Department of Food Science and Technology, Tokyo University of Marine Science and Technology, Tokyo 108-8477, Japan
| | - Hiroki Saeki
- Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan
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2
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Goulet DL, Fraaz U, Zulich CJ, Pilkington TJ, Siemann S. Specificity-directed design of a FRET-quenched heptapeptide for assaying thermolysin-like proteases. Anal Biochem 2020; 604:113826. [PMID: 32622975 DOI: 10.1016/j.ab.2020.113826] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/08/2020] [Indexed: 11/18/2022]
Abstract
Thermolysin (TL) is an industrially important zinc endopeptidase, and the prototype of the M4 family of metallopeptidases. The catalytic function of TL and its relatives is typically assessed using chromogenic or more sensitive fluorescent peptides, with the latter substrates relying on Förster resonance energy transfer (FRET). Here, we demonstrate that a FRET-quenched heptapeptide designed on the basis of the enzyme's substrate specificity (Dabcyl-FKFLGKE-EDANS) is efficiently cleaved by TL and dispase (a TL-like protease) in between the Phe3 and Leu4 residues. The specificity constants (determined at pH 7.4 and 25 °C) for TL and dispase (3.6 × 106 M-1 s-1 and 4.6 × 106 M-1 s-1, respectively) were found to be amongst the highest documented for any TL substrate. Maximal peptide cleavage rates were achieved at pH 6.5 and a temperature of 65 °C. In view of the sensitivity of the assay, concentrations as low as 10 pM TL could be detected. Furthermore, the rate of hydrolysis of Dabcyl-FKFLGKE-EDANS was slow or immeasurable with some other unrelated metallo-, serine- and cysteine proteases, suggesting that the peptide has the potential to serve as a selective substrate for TL and TL-like proteases.
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Affiliation(s)
- Danica L Goulet
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Usama Fraaz
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Carly J Zulich
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Tyson J Pilkington
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada
| | - Stefan Siemann
- Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario, Canada.
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3
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Rosemond SN, Hamadani KM, Cate JHD, Marqusee S. Modulating long-range energetics via helix stabilization: A case study using T4 lysozyme. Protein Sci 2018; 27:2084-2093. [PMID: 30284332 DOI: 10.1002/pro.3521] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/26/2018] [Accepted: 09/27/2018] [Indexed: 11/07/2022]
Abstract
Cooperative protein folding requires distant regions of a protein to interact and provide mutual stabilization. The mechanism of this long-distance coupling remains poorly understood. Here, we use T4 lysozyme (T4L*) as a model to investigate long-range communications across two subdomains of a globular protein. T4L* is composed of two structurally distinct subdomains, although it behaves in a two-state manner at equilibrium. The subdomains of T4L* are connected via two topological connections: the N-terminal helix that is structurally part of the C-terminal subdomain (the A-helix) and a long helix that spans both subdomains (the C-helix). To understand the role that the C-helix plays in cooperative folding, we analyzed a circularly permuted version of T4L* (CP13*), whose subdomains are connected only by the C-helix. We demonstrate that when isolated as individual fragments, both subdomains of CP13* can fold autonomously into marginally stable conformations. The energetics of the N-terminal subdomain depend on the formation of a salt bridge known to be important for stability in the full-length protein. We show that the energetic contribution of the salt bridge to the stability of the N-terminal fragment increases when the C-helix is stabilized, such as occurs upon folding of the C-terminal subdomain. These results suggest a model where long-range energetic coupling is mediated by helix stabilization and not specific tertiary interactions.
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Affiliation(s)
- Sabriya N Rosemond
- California Institute for Quantitative Biosciences, University of California, Berkeley, California, 94720.,Department of Molecular and Cell Biology, University of California, Berkeley, California, 94720-3220
| | - Kambiz M Hamadani
- California Institute for Quantitative Biosciences, University of California, Berkeley, California, 94720.,California State University San Marcos, San Marcos, California, 92096
| | - Jamie H D Cate
- California Institute for Quantitative Biosciences, University of California, Berkeley, California, 94720.,Department of Molecular and Cell Biology, University of California, Berkeley, California, 94720-3220.,Department of Chemistry, University of California, Berkeley, California, 94720
| | - Susan Marqusee
- California Institute for Quantitative Biosciences, University of California, Berkeley, California, 94720.,Department of Molecular and Cell Biology, University of California, Berkeley, California, 94720-3220.,Department of Chemistry, University of California, Berkeley, California, 94720.,Chan Zuckerberg Biohub, San Francisco, CA, 94158
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4
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Cramer J, Krimmer SG, Fridh V, Wulsdorf T, Karlsson R, Heine A, Klebe G. Elucidating the Origin of Long Residence Time Binding for Inhibitors of the Metalloprotease Thermolysin. ACS Chem Biol 2017; 12:225-233. [PMID: 27959500 DOI: 10.1021/acschembio.6b00979] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Kinetic parameters of protein-ligand interactions are progressively acknowledged as valuable information for rational drug discovery. However, a targeted optimization of binding kinetics is not easy to achieve, and further systematic studies are necessary to increase the understanding about molecular mechanisms involved. We determined association and dissociation rate constants for 17 inhibitors of the metalloprotease thermolysin by surface plasmon resonance spectroscopy and correlated kinetic data with high-resolution crystal structures in complex with the protein. From the structure-kinetics relationship, we conclude that the strength of interaction with Asn112 correlates with the rate-limiting step of dissociation. This residue is located at the beginning of a β-strand motif that lines the binding cleft and is commonly believed to align a substrate for catalysis. A reduced mobility of the Asn112 side chain owing to an enhanced engagement in charge-assisted hydrogen bonds prevents the conformational adjustment associated with ligand release and transformation of the enzyme to its open state. This hypothesis is supported by kinetic data of ZFPLA, a known pseudopeptidic inhibitor of thermolysin, which blocks the conformational transition of Asn112. Interference with this retrograde induced-fit mechanism results in variation of the residence time of thermolysin inhibitors by a factor of 74 000. The high conservation of this structural motif within the M4 and M13 metalloprotease families underpins the importance of this feature and has significant implications for drug discovery.
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Affiliation(s)
- Jonathan Cramer
- Institute
of Pharmaceutical Chemistry, University of Marburg, Marbacher
Weg 6, 35032 Marburg, Germany
| | - Stefan G. Krimmer
- Institute
of Pharmaceutical Chemistry, University of Marburg, Marbacher
Weg 6, 35032 Marburg, Germany
| | - Veronica Fridh
- GE Healthcare Bio-Sciences AB, SE-751 84 Uppsala, Sweden
| | - Tobias Wulsdorf
- Institute
of Pharmaceutical Chemistry, University of Marburg, Marbacher
Weg 6, 35032 Marburg, Germany
| | | | - Andreas Heine
- Institute
of Pharmaceutical Chemistry, University of Marburg, Marbacher
Weg 6, 35032 Marburg, Germany
| | - Gerhard Klebe
- Institute
of Pharmaceutical Chemistry, University of Marburg, Marbacher
Weg 6, 35032 Marburg, Germany
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5
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Qiu S, Lai L. Tailoring the pH dependence of human non-pancreatic secretory phospholipase A2 by engineering surface charges. Appl Biochem Biotechnol 2013; 171:1454-64. [PMID: 23955349 DOI: 10.1007/s12010-013-0437-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 08/06/2013] [Indexed: 01/31/2023]
Abstract
Human non-pancreatic secretory phospholipase A2 (hnpsPLA2) catalyzes the sn-2 acyl hydrolysis of phospholipids. It was reported that hnpsPLA2 is involved in various diseases like inflammation, cancer, and so on. This enzyme also exhibits anti-bacterial and anti-virus activities. It is active over a broad pH range, with higher activity at alkaline conditions. In order to make it suitable as a potential bactericide, high activity at neutral pH is preferable. We have tried to tailor the pH dependence of hnpsPLA2 activity by replacing its surface charged residues. Three surface charge replacements, Arg42Glu, Arg100Glu, and Glu89Lys, showed increased activities at neutral pH, which are 2.3, 2.8, and 2.3 times that of the wild-type enzyme at pH 7. Both the positive-to-negative and negative-to-positive mutations lowered the optimum enzymatic reaction pH of hnpsPLA2, indicating that the enzyme pH profile depends on a delicate balance of charged residues. The activity changes are in good agreement with the recently proposed calcium-coordinated catalytic triad mechanism. This study also provides a general means of enhancing hnpsPLA2 activity at low pH.
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Affiliation(s)
- Shunchen Qiu
- BNLMS, State Key Laboratory of Structural Chemistry for Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
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6
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Montpellier LH, Siemann S. Effect of pH on the catalytic function and zinc content of native and immobilized anthrax lethal factor. FEBS Lett 2013; 587:317-21. [DOI: 10.1016/j.febslet.2012.11.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Revised: 11/22/2012] [Accepted: 11/30/2012] [Indexed: 10/27/2022]
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7
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Wang L, Witham S, Zhang Z, Li L, Hodsdon ME, Alexov E. In silico investigation of pH-dependence of prolactin and human growth hormone binding to human prolactin receptor. COMMUNICATIONS IN COMPUTATIONAL PHYSICS 2013; 13:207-222. [PMID: 24683423 PMCID: PMC3966486 DOI: 10.4208/cicp.170911.131011s] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Experimental data shows that the binding of human prolactin (hPRL) to human prolactin receptor (hPRLr-ECD) is strongly pH-dependent, while the binding of the same receptor to human growth hormone (hGH) is pH-independent. Here we carry in silico analysis of the molecular effects causing such a difference and reveal the role of individual amino acids. It is shown that the computational modeling correctly predicts experimentally determined pKa's of histidine residues in an unbound state in the majority of the cases and the pH-dependence of the binding free energy. Structural analysis carried in conjunction with calculated pH-dependence of the binding revealed that the main reason for pH-dependence of the binding of hPRL-hPRLr-ECD is a number of salt- bridges across the interface of the complex, while no salt-bridges are formed in the hGH-hPRlr-ECD. Specifically, most of the salt-bridges involve histidine residues and this is the reason for the pH-dependence across a physiological range of pH. The analysis not only revealed the molecular mechanism of the pH-dependence of the hPRL-hPRLr-ECD, but also provided critical insight into the underlying physic-chemical mechanism.
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Affiliation(s)
- Lin Wang
- Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson, SC 29634
| | - Shawn Witham
- Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson, SC 29634
| | - Zhe Zhang
- Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson, SC 29634
| | - Lin Li
- Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson, SC 29634
| | - Michael E. Hodsdon
- Department of Laboratory Medicine and the Department of Pharmacology, Yale School of Medicine, New Haven, Connecticut 06520
| | - Emil Alexov
- Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson, SC 29634
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8
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Chen F, Zhang F, Du F, Wang A, Gao W, Wang Q, Yin X, Xie T. A novel and efficient method for the immobilization of thermolysin using sodium chloride salting-in and consecutive microwave irradiation. BIORESOURCE TECHNOLOGY 2012; 115:158-163. [PMID: 22153596 DOI: 10.1016/j.biortech.2011.11.059] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 11/14/2011] [Accepted: 11/16/2011] [Indexed: 05/31/2023]
Abstract
Sodium chloride salting-in and microwave irradiation were combined to drive thermolysin molecules into mesoporous support to obtain efficiently immobilized enzyme. When the concentration of sodium chloride was 3 M and microwave power was 40 W, 93.2% of the enzyme was coupled to the support by 3 min, and the maximum specific activity of the immobilized enzyme was 17,925.1 U mg(-1). This was a 4.5-fold increase in activity versus enzyme immobilized using conventional techniques, and a 1.6-fold increase versus free enzyme. Additionally, the thermal stability of the immobilized thermolysin was significantly improved. When incubated at 70°C, there was no reduction in activity by 3.5h, whereas free thermolysin lost most of its activity by 3h. Immobilization also protected the thermolysin against organic solvent denaturation. The microwave-assisted immobilization technique, combined with sodium chloride salting-in, could be applied to other sparsely soluble enzymes immobilization because of its simplicity and high efficiency.
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Affiliation(s)
- Feifei Chen
- Research Center for Biomedicine and Health, Hangzhou Normal University, Hangzhou 310012, PR China
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9
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Morishima A, Yasukawa K, Inouye K. A possibility of a protein-bound water molecule as the ionizable group responsible for pKe at the alkaline side in human matrix metalloproteinase 7 activity. J Biochem 2012; 151:501-9. [PMID: 22368250 DOI: 10.1093/jb/mvs016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human matrix metalloproteinase 7 (MMP-7) activity exhibits broad bell-shaped pH profile with the acidic and alkaline pK(a) (pK(e1) and pK(e2)) values of about 4 and 10. The ionizable group for pK(e2) was assigned to Lys or Arg by thermodynamic analysis; however, no such residues are present in the active site. Hence, based on the crystal structure, we hypothesized that a water molecule bound to the main-chain nitrogen of Ala162 (W1) or the main-chain carbonyl oxygen of Pro217 (W2) is a candidate for the ionizable group for pK(e2) [Takeharu, H. et al. (2011) Biochim. Biophys. Acta 1814, 1940-1946]. In this study, we inspected this hypothesis. In the hydrolysis of (7-methoxycoumarin-4-yl)acetyl-L-Pro-L-Leu-Gly-L-Leu-[N(3)-(2,4-dinitrophenyl)-L-2,3-diaminopropionyl]-L-Ala-L-Arg-NH(2), all 19 variants, in which one of all Lys and Arg residues was replaced by Ala, retained activity, indicating that neither Lys nor Arg is the ionizable group. pK(e2) values of A162S, A162V and A162G were 9.6 ± 0.1, 9.5 ± 0.1 and 10.4 ± 0.2, respectively, different from that of wild-type MMP-7 (WT) (9.9 ± 0.1) by 0.3-0.5 pH unit, and those of P217S, P217V and P217G were 10.1 ± 0.1, 9.8 ± 0.1 and 9.7 ± 0.1, respectively, different from that of WT by 0.1-0.2 pH unit. These results suggest a possibility of W1 or W2 as the ionizable group for pK(e2).
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Affiliation(s)
- Aiko Morishima
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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10
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Abstract
The role of electrostatics in protein-protein interactions and binding is reviewed in this paper. A brief outline of the computational modeling, in the framework of continuum electrostatics, is presented and the basic electrostatic effects occurring upon the formation of the complex are discussed. The effect of the salt concentration and pH of the water phase on protein-protein binding free energy is demonstrated which indicates that the increase of the salt concentration tends to weaken the binding, an observation that is attributed to the optimization of the charge-charge interactions across the interface. It is pointed out that the pH-optimum (pH of optimal binding affinity) varies among the protein-protein complexes, and perhaps is a result of their adaptation to particular subcellular compartments. The similarities and differences between hetero- and homo-complexes are outlined and discussed with respect to the binding mode and charge complementarity.
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Affiliation(s)
- Zhe Zhang
- Computational Biophysics and Bioinformatics, Department of Physics, Clemson University, Clemson,SC 29634, USA
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11
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Kusano M, Yasukawa K, Inouye K. Synthesis of N-carbobenzoxy-l-aspartyl-l-phenylalanine methyl ester catalyzed by thermolysin variants with improved activity. Enzyme Microb Technol 2010. [DOI: 10.1016/j.enzmictec.2009.12.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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S1 site residues of Lactococcus lactis prolidase affect substrate specificity and allosteric behaviour. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2009; 1794:1715-24. [PMID: 19682610 DOI: 10.1016/j.bbapap.2009.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 07/22/2009] [Accepted: 08/04/2009] [Indexed: 12/16/2022]
Abstract
Lactococcus lactis prolidase preferably hydrolyzes Xaa-Pro dipeptides where Xaa is a hydrophobic amino acid. Anionic Glu-Pro and Asp-Pro dipeptides cannot be hydrolyzed at any observable rates and the hydrolysis of cationic Arg-Pro and Lys-Pro dipeptides is at about one tenth of the rate of Leu-Pro. It was hypothesized that the hydrophobic residues in the S1 site were responsible for this substrate specificity, thus the residues in the S1 site were substituted with hydrophilic residues. The substitution of Leu193 and Val302 revealed that these residues influenced the substrate specificity. The introduction of a cationic residue, L193R, allowed Asp-Pro to be utilized as a substrate at 37.0% of the rate of Leu-Pro, and the anionic mutation, V302D, yielded mutants that could hydrolyze Asp-Pro, Arg-Pro and Lys-Pro at 25.9 to 57.4% rates. Interestingly, these mutants of S1 site residues eliminated the allosteric behaviour of L. lactis prolidase that makes this enzyme unique among known prolidases. Results of pH dependency, thermal dependency, and molecular modelling suggested that these observed changes were due to the alteration of the interactions among catalytic zinc cations, Arg293, His296, and the mutated residues.
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13
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Kusano M, Yasukawa K, Inouye K. Insights into the Catalytic Roles of the Polypeptide Regions in the Active Site of Thermolysin and Generation of the Thermolysin Variants with High Activity and Stability. J Biochem 2008; 145:103-13. [DOI: 10.1093/jb/mvn140] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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14
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Effects of introducing negative charges into the molecular surface of thermolysin by site-directed mutagenesis on its activity and stability. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1784:481-8. [DOI: 10.1016/j.bbapap.2007.12.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Revised: 11/12/2007] [Accepted: 12/10/2007] [Indexed: 11/22/2022]
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15
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Yasukawa K, Inouye K. Improving the activity and stability of thermolysin by site-directed mutagenesis. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2007; 1774:1281-8. [PMID: 17869197 DOI: 10.1016/j.bbapap.2007.08.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2007] [Revised: 07/11/2007] [Accepted: 08/06/2007] [Indexed: 10/23/2022]
Abstract
In previous site-directed mutagenesis study on thermolysin, mutations which increase the catalytic activity or the thermal stability have been identified. In this study, we attempted to generate highly active and stable thermolysin by combining the mutations so far revealed to be effective. Three mutant enzymes, L144S (Leu144 in the central alpha-helix located at the bottom of the active site cleft is replaced with Ser), G8C/N60C/S65P (Gly8, Asn60, and Ser65 in the N-terminal region are replaced with Cys, Cys, and Pro, respectively, to introduce a disulfide bridge between the positions 8 and 60), and G8C/N60C/S65P/L144S, were constructed by site-directed mutagenesis. In the hydrolysis of N-[3-(2-furyl)acryloyl]-glycyl-L-leucine amide (FAGLA) and N-carbobenzoxy-L-aspartyl-L-phenylalanine methyl ester (ZDFM), the k(cat)/K(m) values of L144S and G8C/N60C/S65P/L144S were 5- to 10-fold higher than that of the wild-type enzyme. The rate constants for thermal inactivation at 70 degrees C and 80 degrees C of G8C/N60C/S65P and G8C/N60C/S65P/L144S decreased to 50% of that of the wild-type enzyme. These results indicate that G8C/N60C/S65P/L144S is more active and stable than the wild-type thermolysin. Thermodynamic analysis suggests that the single mutation of Leu144-->Ser and the triple mutation of Gly8-->Cys, Asn60-->Cys, and Ser65-->Pro are independent.
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Affiliation(s)
- Kiyoshi Yasukawa
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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16
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Inouye K, Kusano M, Hashida Y, Minoda M, Yasukawa K. Engineering, expression, purification, and production of recombinant thermolysin. BIOTECHNOLOGY ANNUAL REVIEW 2007; 13:43-64. [PMID: 17875473 DOI: 10.1016/s1387-2656(07)13003-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Thermolysin [EC 3.4.24.27] is a thermostable neutral zinc metalloproteinase originally identified in the culture broth of Bacillus thermoproteolyticus Rokko. Since the discovery in 1962, the enzyme has been extensively studied regarding its structure and catalytic mechanism. Today, thermolysin is a representative of zinc metalloproteinase and an attractive target in protein engineering to understand the catalytic mechanism, thermostability, and halophilicity. Thermolysin is used in industry, especially for the enzymatic synthesis of N-carbobenzoxy L-Asp-L-Phe methyl ester (ZDFM), a precursor of an artificial sweetener, aspartame. Generation of genetically engineered thermolysin with higher activity in the synthesis of ZDFM has been highly desired. In accordance with the expansion of studies on thermolysin, various strategies for its expression and purification have been devised and successfully used. In this review, we aim to outline recombinant thermolysins associated with their engineering, expression, purification, and production.
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Affiliation(s)
- Kuniyo Inouye
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
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