1
|
Liang H, Zhang X, Hou Y, Zheng K, Hao H, He B, Li H, Sun C, Yang T, Song H, Cai R, Wang Y, Jiang H, Qi L, Wang Y. Super-high procoagulant activity of gecko thrombin: A gift from sky dragon. CNS Neurosci Ther 2023; 29:3081-3093. [PMID: 37144588 PMCID: PMC10493662 DOI: 10.1111/cns.14250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 04/06/2023] [Accepted: 04/17/2023] [Indexed: 05/06/2023] Open
Abstract
AIMS Gecko, the "sky dragon" named by Traditional Chinese Medicine, undergoes rapid coagulation and scarless regeneration following tail amputation in the natural ecology, providing a perfect opportunity to develop the efficient and safe drug for blood clotting. Here, gecko thrombin (gthrombin) was recombinantly prepared and comparatively studied on its procoagulant activity. METHODS The 3D structure of gthrombin was constructed using the homology modeling method of I-TASSER. The active gthrombin was prepared by the expression of gecko prethrombin-2 in 293 T cells, followed by purification with Ni2+ -chelating column chromatography prior to activation by snake venom-derived Ecarin. The enzymatic activities of gthrombin were assayed by hydrolysis of synthetic substrate S-2238 and the fibrinogen clotting. The vulnerable nerve cells were used to evaluate the toxicity of gthrombin at molecular and cellular levels. RESULTS The active recombinant gthrombin showed super-high catalytic and fibrinogenolytic efficiency than those of human under different temperatures and pH conditions. In addition, gthrombin made nontoxic effects on the central nerve cells including neurons, contrary to those of mammalian counterparts, which contribute to neuronal damage, astrogliosis, and demyelination. CONCLUSIONS A super-high activity but safe procoagulant candidate drug was identified from reptiles, which provided a promising perspective for clinical application in rapid blood clotting.
Collapse
Affiliation(s)
- Hao Liang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Xingyuan Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Yuxuan Hou
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Kang Zheng
- Anti‐aging & Regenerative Medicine Research Institution, School of Life Sciences and MedicineShandong University of TechnologyZiboPR China
| | - Huifei Hao
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Bingqiang He
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Hui Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Chunshuai Sun
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Ting Yang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Honghua Song
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Rixin Cai
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Yingjie Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| | - Haiyan Jiang
- Department of Emergency MedicineAffiliated Hospital of Nantong UniversityNantongPR China
| | - Lei Qi
- Department of Emergency MedicineAffiliated Hospital of Nantong UniversityNantongPR China
| | - Yongjun Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co‐innovation Center of NeuroregenerationNantong UniversityNantongPR China
| |
Collapse
|
2
|
Vecchio FL, Bisceglia P, Imbimbo BP, Lozupone M, Latino RR, Resta E, Leone M, Solfrizzi V, Greco A, Daniele A, Watling M, Panza F, Seripa D. Are apolipoprotein E fragments a promising new therapeutic target for Alzheimer’s disease? Ther Adv Chronic Dis 2022; 13:20406223221081605. [PMID: 35321401 PMCID: PMC8935560 DOI: 10.1177/20406223221081605] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 01/28/2022] [Indexed: 11/17/2022] Open
Abstract
Human apolipoprotein E (ApoE) is a 299-amino acid secreted glycoprotein that binds cholesterol and phospholipids. ApoE exists as three common isoforms (ApoE2, ApoE3, and ApoE4) and heterozygous carriers of the ε4 allele of the gene encoding ApoE (APOE) have a fourfold greater risk of developing Alzheimer’s disease (AD). The enzymes thrombin, cathepsin D, α-chymotrypsin-like serine protease, and high-temperature requirement serine protease A1 are responsible for ApoE proteolytic processing resulting in bioactive C-terminal-truncated fragments that vary depending on ApoE isoforms, brain region, aging, and neural injury. The objectives of the present narrative review were to describe ApoE processing, discussing current hypotheses about the potential role of various ApoE fragments in AD pathophysiology, and reviewing the current development status of different anti-ApoE drugs. The exact mechanism by which APOE gene variants increase/decrease AD risk and the role of ApoE fragments in the deposition are not fully understood, but APOE is known to directly affect tau-mediated neurodegeneration. ApoE fragments co-localize with neurofibrillary tangles and amyloid β (Aβ) plaques, and may cause neurodegeneration. Among anti-ApoE approaches, a fascinating strategy may be to therapeutically overexpress ApoE2 in APOE ε4/ε4 carriers through vector administration or liposomal delivery systems. Another approach involves reducing ApoE4 expression by intracerebroventricular antisense oligonucleotides that significantly decreased Aβ pathology in transgenic mice. Differences in the proteolytic processing of distinct ApoE isoforms and the use of ApoE fragments as mimetic peptides in AD treatment are also under investigation. Treatment with peptides that mimic the structural and biological properties of native ApoE may reduce Aβ deposition, tau hyperphosphorylation, and glial activation in mouse models of Aβ pathology. Alternative strategies involve the use of ApoE4 structure correctors, passive immunization to target a certain form of ApoE, conversion of the ApoE4 aminoacid sequence into that of ApoE3 or ApoE2, and inhibition of the ApoE-Aβ interaction.
Collapse
Affiliation(s)
- Filomena Lo Vecchio
- Research Laboratory, Complex Structure of Geriatrics, Department of Medical Sciences, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia 71013, Italy
| | - Paola Bisceglia
- Research Laboratory, Complex Structure of Geriatrics, Department of Medical Sciences, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | | | - Madia Lozupone
- Neurodegenerative Disease Unit, Department of Basic Medicine, Neuroscience, and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Raffaela Rita Latino
- Complex Structure of Neurology, Department of Medical Sciences, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Emanuela Resta
- Translational Medicine and Management of Health Systems, University of Foggia, Foggia, Italy
| | - Maurizio Leone
- Complex Structure of Neurology, Department of Medical Sciences, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Vincenzo Solfrizzi
- ‘Cesare Frugoni’ Internal and Geriatric Medicine and Memory Unit, University of Bari ‘Aldo Moro’, Bari, Italy
| | - Antonio Greco
- Department of Neuroscience, Catholic University of the Sacred Heart, Rome, Italy; Neurology Unit, IRCCS Fondazione Policlinico Universitario A. Gemelli, Rome, Italy
- Research Laboratory, Complex Structure of Geriatrics, Department of Medical Sciences, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | | | - Mark Watling
- CNS & Pain Department, TranScrip Ltd, Reading, UK
| | - Francesco Panza
- Research Laboratory, Complex Structure of Geriatrics, Department of Medical Sciences, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy
- Population Health Unit, Healthy Aging Phenotypes Research Unit, ‘Salus in Apulia Study’, National Institute of Gastroenterology ‘Saverio de Bellis’, Research Hospital, Castellana Grotte, Bari 70013, Italy
| | - Davide Seripa
- Research Laboratory, Complex Structure of Geriatrics, Department of Medical Sciences, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
- Hematology and Stem Cell Transplant Unit, ‘Vito Fazzi’ Hospital, Lecce, Italy
| |
Collapse
|
3
|
Crawley EM, Pye S, Forbes BE, Raston CL. Vortex Fluidic Mediated Oxidative Sulfitolysis of Oxytocin. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27031109. [PMID: 35164375 PMCID: PMC8840205 DOI: 10.3390/molecules27031109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/03/2022] [Accepted: 02/04/2022] [Indexed: 11/18/2022]
Abstract
In peptide production, oxidative sulfitolysis can be used to protect the cysteine residues during purification, and the introduction of a negative charge aids solubility. Subsequent controlled reduction aids in ensuring correct disulfide bridging. In vivo, these problems are overcome through interaction with chaperones. Here, a versatile peptide production process has been developed using an angled vortex fluidic device (VFD), which expands the viable pH range of oxidative sulfitolysis from pH 10.5 under batch conditions, to full conversion within 20 min at pH 9–10.5 utilising the VFD. VFD processing gave 10-fold greater conversion than using traditional batch processing, which has potential in many applications of the sulfitolysis reaction.
Collapse
Affiliation(s)
- Emily M. Crawley
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia; (E.M.C.); (S.P.)
| | - Scott Pye
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia; (E.M.C.); (S.P.)
| | - Briony E. Forbes
- Flinders Health and Medical Research Institute, College of Medicine and Public Health, Flinders University, Adelaide, SA 5042, Australia;
| | - Colin L. Raston
- Flinders Institute for Nanoscale Science and Technology, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia; (E.M.C.); (S.P.)
- Correspondence:
| |
Collapse
|
4
|
Wu D, Xiao J, Salsbury FR. Light Chain Mutation Effects on the Dynamics of Thrombin. J Chem Inf Model 2021; 61:950-965. [PMID: 33450154 DOI: 10.1021/acs.jcim.0c01303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Thrombin plays an important role in the process of hemostasis and blood coagulation. Studies in thrombin can help us find ways to treat cancer because thrombin is able to reduce the characteristic hypercoagulability of cancer. Thrombin is composed of two chains, the light chain and the heavy chain. The function of the heavy chain has been largely explored, while the function of the light chain was obscured until several disease-associated mutations in the light chain come to light. In this study, we want to explore the dynamic and conformation effects of mutations on the light chain further to determine possible associations between mutation, conformational changes, and disease. The study, which is a follow-up for our studies on apo thrombin and the mutant, ΔK9, mainly focuses on the mutants E8K and R4A. E8K is a disease-associated mutation, and R4A is used to study the role of Arg4, which is suggested experimentally to play a critical role for thrombin's catalytic activities. We performed five all-atom one microsecond-scale molecular dynamics (MD) simulations for both E8K and R4A, and quantified the changes in the conformational ensemble of the mutants. From the root-mean-square fluctuations (RMSF) for the α-carbons, we find that the atomic fluctuations change in the mutants in the 60s loop and γ loop. The correlation coefficients for the α-carbons indicate that the correlation relation for atom-pairs in the protein is also impacted. The clustering analysis and the principal component analysis (PCA) consistently tell us that the catalytic pocket and the regulatory loops are destabilized by the mutations. We also find that there are two binding modes for Na+ by clustering the vector difference between the Na+ ions and the 220s loop. After further analysis, we find that there is a relation between the Na+ binding and the rigidification of the γ loop, which may shed light on the mysterious role of the γ loop in thrombin.
Collapse
Affiliation(s)
- Dizhou Wu
- Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27106 United States
| | - Jiajie Xiao
- Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27106 United States.,Freenome, South San Francisco, California 94080 United States
| | - Freddie R Salsbury
- Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27106 United States
| |
Collapse
|
5
|
Barkhordari A, Behzad-Behbahani A, Jajarmi V, Bandehpour M, Rafiei-Dehbidi G, Safari F, Mahboudi F, Kazemi B. Direct Cloning, Expression and Purification of Human Activated Thrombin in Prokaryotic System and CD Analysis Report of Produced Thrombin: Molecular Characterization of Recombinant Thrombin. Int J Pept Res Ther 2020. [DOI: 10.1007/s10989-020-10046-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
6
|
Xiao J, Melvin RL, Salsbury FR. Probing light chain mutation effects on thrombin via molecular dynamics simulations and machine learning. J Biomol Struct Dyn 2019; 37:982-999. [PMID: 29471734 PMCID: PMC6207482 DOI: 10.1080/07391102.2018.1445032] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 02/17/2018] [Indexed: 12/13/2022]
Abstract
Thrombin is a key component for chemotherapeutic and antithrombotic therapy development. As the physiologic and pathologic roles of the light chain still remain vague, here, we continue previous efforts to understand the impacts of the disease-associated single deletion of LYS9 in the light chain. By combining supervised and unsupervised machine learning methodologies and more traditional structural analyses on data from 10 μs molecular dynamics simulations, we show that the conformational ensemble of the ΔK9 mutant is significantly perturbed. Our analyses consistently indicate that LYS9 deletion destabilizes both the catalytic cleft and regulatory functional regions and result in some conformational changes that occur in tens to hundreds of nanosecond scaled motions. We also reveal that the two forms of thrombin each prefer a distinct binding mode of a Na+ ion. We expand our understanding of previous experimental observations and shed light on the mechanisms of the LYS9 deletion associated bleeding disorder by providing consistent but more quantitative and detailed structural analyses than early studies in literature. With a novel application of supervised learning, i.e. the decision tree learning on the hydrogen bonding features in the wild-type and ΔK9 mutant forms of thrombin, we predict that seven pairs of critical hydrogen bonding interactions are significant for establishing distinct behaviors of wild-type thrombin and its ΔK9 mutant form. Our calculations indicate the LYS9 in the light chain has both localized and long-range allosteric effects on thrombin, supporting the opinion that light chain has an important role as an allosteric effector.
Collapse
Affiliation(s)
- Jiajie Xiao
- Department of Physics, Wake Forest University, Winston-Salem, USA
- Department of Computer Science, Wake Forest University, Winston Salem, USA
| | - Ryan L. Melvin
- Department of Physics, Wake Forest University, Winston-Salem, USA
- Department of Mathematics and Statistics, Wake Forest University, Winston-Salem,USA
| | | |
Collapse
|
7
|
Wood DC, Pelc LA, Pozzi N, Wallisch M, Verbout NG, Tucker EI, Gruber A, Di Cera E. WEDGE: an anticoagulant thrombin mutant produced by autoactivation. J Thromb Haemost 2015; 13:111-4. [PMID: 25369995 PMCID: PMC4368433 DOI: 10.1111/jth.12774] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Indexed: 11/29/2022]
Abstract
BACKGROUND The production of therapeutically relevant proteases typically involves activation of a zymogen precursor by external enzymes, which may raise regulatory issues about availability and purity. Recent studies of thrombin precursors have shown how to engineer constructs that spontaneously convert to the mature protease by autoactivation, without the need for external enzymes. OBJECTIVES Autoactivation is an innovative strategy that promises to simplify the production of proteases of therapeutic relevance, but has not been tested in practical applications. The aim of this study was to provide a direct test of this strategy. METHODS An autoactivating version of the thrombin mutant W215A/E217A (WE), which is currently in preclinical development as an anticoagulant, was engineered. RESULTS AND CONCLUSIONS The autoactivating version of WE can be produced in large quantities, like WE made in BHK cells or Escherichia coli, and retains all significant functional properties in vitro and in vivo. The results serve as proof of principle that autoactivation is an innovative and effective strategy for the production of trypsin-like proteases of therapeutic relevance.
Collapse
Affiliation(s)
- D C Wood
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO, USA
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Osadská M, Boňková H, Krahulec J, Stuchlík S, Turňa J. Optimization of expression of untagged and histidine-tagged human recombinant thrombin precursors in Escherichia coli. Appl Microbiol Biotechnol 2014; 98:9259-70. [PMID: 24878753 DOI: 10.1007/s00253-014-5840-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Revised: 05/09/2014] [Accepted: 05/15/2014] [Indexed: 10/25/2022]
Abstract
The present study is focused on preparation of proper Escherichia coli expression system to ensure high yields of various modified precursors of human recombinant thrombin, a potential biopharmaceutical reagent. Two thrombin precursors, the smallest single-chain α-thrombin precursor prethrombin-2 and its shortened form prethrombin-2∆13, and their His-tagged forms were used. In order to determine the effect of the different lengths and amino acid compositions of affinity His-tag on the target protein expression level, a variety of the His-tag sequences were used. We found out that the protein expression efficiency was closely related to the codons used for encoding of amino acids of fusion histidine tag. Optimization of culture medium composition is another way to increase yield of the target protein. Suitable medium composition can ensure cell growth to high densities which is related to total yield of expressed protein. In this study, a new optimized complex medium for batch fermentation was developed. Addition of nutrients like a yeast extract and enzymatic casein hydrolysate to the defined medium components had a positive impact on protein expression, where relatively high expression level of the target protein from total amount of cellular proteins was achieved. Further, we have focused on trace element solution composition, and the optimized nickel and selenium concentrations were determined. Our results show that the composition of essential trace metal solution has a major impact not only on expression level, but it can also affect cell growth rate.
Collapse
Affiliation(s)
- Michaela Osadská
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, 842 15, Bratislava 4, Slovak Republic,
| | | | | | | | | |
Collapse
|
9
|
Bhakta V, Gierczak RF, Sheffield WP. Expression screening of bacterial libraries of recombinant alpha-1 proteinase inhibitor variants for candidates with thrombin inhibitory capacity. J Biotechnol 2013; 168:373-81. [DOI: 10.1016/j.jbiotec.2013.10.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 10/03/2013] [Accepted: 10/07/2013] [Indexed: 11/30/2022]
|
10
|
Pozzi N, Chen Z, Zapata F, Niu W, Barranco-Medina S, Pelc LA, Di Cera E. Autoactivation of thrombin precursors. J Biol Chem 2013; 288:11601-10. [PMID: 23467412 DOI: 10.1074/jbc.m113.451542] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Trypsin-like proteases are synthesized as inactive zymogens and convert to the mature form upon activation by specific enzymes, often assisted by cofactors. Central to this paradigm is that the zymogen does not convert spontaneously to the mature enzyme, which in turn does not feed back to activate its zymogen form. In the blood, the zymogens prothrombin and prethrombin-2 require the prothrombinase complex to be converted to the mature protease thrombin, which is unable to activate prothrombin or prethrombin-2. Here, we show that replacement of key residues within the activation domain causes these zymogens to spontaneously convert to thrombin. The conversion is started by the zymogen itself, which is capable of binding ligands at the active site, and is abrogated by inactivation of the catalytic residue Ser-195. The product of autoactivation is functionally and structurally equivalent to wild-type thrombin. Zymogen autoactivation is explained by conformational selection, a basic property of the trypsin fold uncovered by structural and rapid kinetics studies. Both the zymogen and protease undergo a pre-existing equilibrium between active and inactive forms. The equilibrium regulates catalytic activity in the protease and has the potential to unleash activity in the zymogen to produce autoactivation. A new strategy emerges for the facile production of enzymes through zymogen autoactivation that is broadly applicable to trypsin-like proteases of biotechnological and clinical interest.
Collapse
Affiliation(s)
- Nicola Pozzi
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104, USA
| | | | | | | | | | | | | |
Collapse
|
11
|
Virel A, Saa L, Pavlov V. Quantification of prothrombin in human plasma amplified by autocatalytic reaction. Anal Chem 2012; 84:2380-7. [PMID: 22324776 DOI: 10.1021/ac203138y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
By site directed mutagenesis, we have produced recombinant mutants of human and mouse prethrombin-2 which are able to convert themselves autocatalytically into α-thrombin. We also have created a new method to amplify the signal of bioanalytical assays based on the autocatalytic activation of these mutated proenzymes. The activation of the mutants by active α-thrombin triggers an autocatalytic reaction which leads to more active thrombin resulting in the amplification of the readout signal. Addition of mutated mouse prethrombin-2 into the conventional assay for prothrombin level in human plasma, employing ecarin and the fluorogenic substrate, resulted in improvement of the detection limit by 2 orders of magnitude.
Collapse
Affiliation(s)
- Ana Virel
- CIC biomaGUNE, Parque Tecnológico de San Sebastián, Paseo Miramón 182, 20009, San Sebastián, Spain
| | | | | |
Collapse
|
12
|
Di Cera E. Thrombin as an Anticoagulant. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 99:145-84. [DOI: 10.1016/b978-0-12-385504-6.00004-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
13
|
Rudolph R, Lange C. Strategies for the Oxidative in vitro Refolding of Disulfide-bridge-containing Proteins. OXIDATIVE FOLDING OF PEPTIDES AND PROTEINS 2008. [DOI: 10.1039/9781847559265-00192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Rainer Rudolph
- Institut für Biochemie and Biotechnologie Martin-Luther-Universität Halle-Wittenberg Kurt-Mothes-Str. 3 06120 Halle (Saale) Germany
| | - Christian Lange
- Institut für Biochemie and Biotechnologie Martin-Luther-Universität Halle-Wittenberg Kurt-Mothes-Str. 3 06120 Halle (Saale) Germany
| |
Collapse
|
14
|
Abstract
Thrombin is a Na+-activated, allosteric serine protease that plays opposing functional roles in blood coagulation. Binding of Na+ is the major driving force behind the procoagulant, prothrombotic and signaling functions of the enzyme, but is dispensable for cleavage of the anticoagulant protein C. The anticoagulant function of thrombin is under the allosteric control of the cofactor thrombomodulin. Much has been learned on the mechanism of Na+ binding and recognition of natural substrates by thrombin. Recent structural advances have shed light on the remarkable molecular plasticity of this enzyme and the molecular underpinnings of thrombin allostery mediated by binding to exosite I and the Na+ site. This review summarizes our current understanding of the molecular basis of thrombin function and allosteric regulation. The basic information emerging from recent structural, mutagenesis and kinetic investigation of this important enzyme is that thrombin exists in three forms, E*, E and E:Na+, that interconvert under the influence of ligand binding to distinct domains. The transition between the Na+ -free slow from E and the Na+ -bound fast form E:Na+ involves the structure of the enzyme as a whole, and so does the interconversion between the two Na+ -free forms E* and E. E* is most likely an inactive form of thrombin, unable to interact with Na + and substrate. The complexity of thrombin function and regulation has gained this enzyme pre-eminence as the prototypic allosteric serine protease. Thrombin is now looked upon as a model system for the quantitative analysis of biologically important enzymes.
Collapse
Affiliation(s)
- Enrico Di Cera
- Department of Biochemistry and Molecular Biophysics, Washington University Medical School, St. Louis, MO 63110, United States.
| |
Collapse
|
15
|
Bush-Pelc LA, Marino F, Chen Z, Pineda AO, Mathews FS, Di Cera E. Important role of the cys-191 cys-220 disulfide bond in thrombin function and allostery. J Biol Chem 2007; 282:27165-27170. [PMID: 17636263 DOI: 10.1074/jbc.m703202200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Little is known on the role of disulfide bonds in the catalytic domain of serine proteases. The Cys-191-Cys-220 disulfide bond is located between the 190 strand leading to the oxyanion hole and the 220-loop that contributes to the architecture of the primary specificity pocket and the Na+ binding site in allosteric proteases. Removal of this bond in thrombin produces an approximately 100-fold loss of activity toward several chromogenic and natural substrates carrying Arg or Lys at P1. Na+ activation is compromised, and no fluorescence change can be detected in response to Na+ binding. A 1.54-A resolution structure of the C191A/C220A mutant in the free form reveals a conformation similar to the Na+-free slow form of wild type. The lack of disulfide bond exposes the side chain of Asp-189 to solvent, flips the backbone O atom of Gly-219, and generates disorder in portions of the 186 and 220 loops defining the Na+ site. This conformation, featuring perturbation of the Na+ site but with the active site accessible to substrate, offers a possible representation of the recently identified E* form of thrombin. Disorder in the 186 and 220 loops and the flip of Gly-219 are corrected by the active site inhibitor H-D-Phe-Pro-Arg-CH(2)Cl, as revealed by the 1.8-A resolution structure of the complex. We conclude that the Cys-191-Cys-220 disulfide bond confers stability to the primary specificity pocket by shielding Asp-189 from the solvent and orients the backbone O atom of Gly-219 for optimal substrate binding. In addition, the disulfide bond stabilizes the 186 and 220 loops that are critical for Na+ binding and activation.
Collapse
Affiliation(s)
- Leslie A Bush-Pelc
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Francesca Marino
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Zhiwei Chen
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Agustin O Pineda
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - F Scott Mathews
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Enrico Di Cera
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110.
| |
Collapse
|
16
|
Abstract
Thrombin is a dual action serine protease in the blood clotting cascade. Similar to other clotting factors, thrombin is mainly present in the blood in a zymogen form, prothrombin. Although the two cleavage events required to activate thrombin are well-known, little is known about why the thrombin precursors are inactive proteases. Although prothrombin is much larger than thrombin, prethrombin-2, which contains all of the same amino acids as thrombin, but has not yet been cleaved between Arg320 and Ile321, remains inactive. Crystal structures of both prethrombin-2 and thrombin are available and show almost no differences in the active site conformations. Slight differences were, however, seen in the loops surrounding the active site, which are larger in thrombin than in most other trypsin-like proteases, and have been shown to be important for substrate specificity. To explore whether the dynamics of the active site loops were different in the various zymogen forms of thrombin, we employed amide H/(2)H exchange experiments to compare the exchange rates of regions of thrombin with the same regions of prothrombin, prethrombin-2, and meizothrombin. Many of the surface loops showed less exchange in the zymogen forms, including the large loop corresponding to anion binding exosite 1. Conversely, the autolysis loop and sodium-binding site exchanged more readily in the zymogen forms. Prothrombin and prethrombin-2 gave nearly identical results while meizothrombin in some regions more closely resembled active thrombin. Thus, cleavage of the Arg320-Ile321 peptide bond is the key to formation of the active enzyme, which involves increased dynamics of the substrate-binding loops and decreased dynamics of the catalytic site.
Collapse
Affiliation(s)
| | - Elizabeth A. Komives
- Author to whom correspondence should be addressed: Department of Chemistry and Biochemistry, U. C. San Diego, La Jolla, CA 92093-0378, ph: (858) 534-3058, FAX: (858) 534-6174,
| |
Collapse
|
17
|
Johnson D, Adams T, Li W, Huntington J. Crystal structure of wild-type human thrombin in the Na+-free state. Biochem J 2006; 392:21-8. [PMID: 16201969 PMCID: PMC1317660 DOI: 10.1042/bj20051217] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Regulation of thrombin activity is critical for haemostasis and the prevention of thrombosis. Thrombin has several procoagulant substrates, including fibrinogen and platelet receptors, and essential cofactors for stimulating its own formation. However, thrombin is also capable of serving an anticoagulant function by activating protein C. The specificity of thrombin is primarily regulated by binding to the cofactor TM (thrombomodulin), but co-ordination of Na+ can also affect thrombin activity. The Na+-free form is often referred to as 'slow' because of reduced rates of cleavage of procoagulant substrates, but the slow form is still capable of rapid activation of protein C in the presence of TM. The molecular basis of the slow proteolytic activity of thrombin has remained elusive, in spite of two decades of solution studies and many published crystallographic structures. In the present paper, we report the first structure of wild-type unliganded human thrombin grown in the absence of co-ordinating Na+. The Na+-binding site is observed in a highly ordered position 6 A (1 A=0.1 nm) removed from that seen in the Na+-bound state. The movement of the Na+ loop results in non-catalytic hydrogen-bonding in the active site and blocking of the S1 and S2 substrate-binding pockets. Similar, if more dramatic, changes were observed in a previous structure of the constitutively slow thrombin variant E217K. The slow behaviour of thrombin in solutions devoid of Na+ can now be understood in terms of an equilibrium between an inert species, represented by the crystal structure described in the present paper, and an active form, where the addition of Na+ populates the active state.
Collapse
Affiliation(s)
- Daniel J. D. Johnson
- University of Cambridge, Department of Haematology, Division of Structural Medicine, Thrombosis Research Unit, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 2XY, U.K
| | - Ty E. Adams
- University of Cambridge, Department of Haematology, Division of Structural Medicine, Thrombosis Research Unit, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 2XY, U.K
| | - Wei Li
- University of Cambridge, Department of Haematology, Division of Structural Medicine, Thrombosis Research Unit, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 2XY, U.K
| | - James A. Huntington
- University of Cambridge, Department of Haematology, Division of Structural Medicine, Thrombosis Research Unit, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 2XY, U.K
- To whom correspondence should be addressed (email )
| |
Collapse
|
18
|
Cui ZF, Guan YX, Chen JL, Yao SJ. Thermosensitive poly(N-isopropylacrylamide) hydrogel for refolding of recombinant bovine prethrombin-2 fromE. coli inclusion bodies. J Appl Polym Sci 2005. [DOI: 10.1002/app.21640] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
19
|
Menzella HG, Gramajo HC, Ceccarelli EA. High recovery of prochymosin from inclusion bodies using controlled air oxidation. Protein Expr Purif 2002; 25:248-55. [PMID: 12135557 DOI: 10.1016/s1046-5928(02)00006-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Refolding of proteins from inclusion bodies is a field of increasing interest for obtaining large amounts of active enzymes. Consequently, the development of inexpensive and scalable processes is required. This is particularly challenging in the case of eukaryotic proteins containing cysteines, which may form disulfide bonds in the native active protein. Previous studies have shown that the formation of disulfide bonds is essential for the refolding of prochymosin. In this work we demonstrate that air oxidation can be efficiently used for the refolding of prochymosin and that 48% of the unfolded protein can be recovered as active enzyme at a final protein concentration of 0.8 mg/ml. Refolding of the protein strictly correlates with the change in pH of the refolding solution. We were able to follow the degree of oxidative renaturation of the prochymosin by simply measuring pH. Thus, the scaling up of the refolding system under controlled conditions was easily achieved. Analyses of different substances as folding aids indicate that the use of L-arginine or neutral surfactants improves the recovery of active protein up to 67% of the initial protein. The overall results indicate that prochymosin can be efficiently and inexpensively refolded with high yields by controlled air oxidation.
Collapse
Affiliation(s)
- Hugo G Menzella
- Microbiology Division, Instituto de Biología Molecular y Celular de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, (S2002LRK), Argentina
| | | | | |
Collapse
|
20
|
Babé LM, Linnevers CJ, Schmidt BF. Production of active mammalian and viral proteases in bacterial expression systems. Biotechnol Genet Eng Rev 2001; 17:213-52. [PMID: 11255667 DOI: 10.1080/02648725.2000.10647993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- L M Babé
- Axys Pharmaceuticals Inc., 180 Kimball Way, South San Francisco, CA 94080, USA.
| | | | | |
Collapse
|
21
|
Ambrus A, Fésüs L. Polyethylene glycol enhanced refolding of the recombinant human tissue transglutaminase. Prep Biochem Biotechnol 2001; 31:59-70. [PMID: 11321164 DOI: 10.1081/pb-100103372] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Tissue transglutaminase forms cross-links between lysine and glutamine side-chains of polypeptide chains in a Ca2+-dependent reaction; its structural basis is still not clarified. In this study, we demonstrate that the refolding of the human recombinant enzyme molecule to its catalytically active form from inclusion bodies needs the presence of a helper material with higher molecular mass, but only in the initiation phase. Ca2+ and nucleotides are ascribed as affector molecules also in the early phase of structural reconstitution. Two optimal concentrations of polyethylene glycol and a relatively long time scale for the evolution of the final structure were identified. The optimized refolding procedure is reported.
Collapse
Affiliation(s)
- A Ambrus
- University of Debrecen, Department of Biochemistry and Molecular Biology, Hungary
| | | |
Collapse
|
22
|
Su NY, Yu CJ, Shen HD, Pan FM, Chow LP. Pen c 1, a novel enzymic allergen protein from Penicillium citrinum. Purification, characterization, cloning and expression. EUROPEAN JOURNAL OF BIOCHEMISTRY 1999; 261:115-23. [PMID: 10103041 DOI: 10.1046/j.1432-1327.1999.00242.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A 33-kDa alkaline serine protease secreted by Penicillium citrinum strain 52-5 is shown to be an allergenic agent in this fungus. The protein, designated Pen c 1, was purified by sequential DEAE-Sepharose and carboxymethyl (CM)-Sepharose chromatographies. Pen c 1 has a molecular mass of 33 kDa and a pI of 7.1. The caseinolytic enzyme activity of this protein was studied. The protein binds to serum IgE from patients allergic to Penicillium citrinum. The cDNA encoding Pen c 1 is 1420 bp in length and contains an open reading frame for a 397-amino-acid polypeptide. Pen c 1 codes for a larger precursor containing a signal peptide, a propeptide and the 33-kDa mature protein. Sequence comparison revealed that Pen c 1 possesses several features in common with the alkaline serine proteases of the subtilisin family. The essential Asp, His, and Ser residues that make up the catalytic triad of serine proteases are well conserved. Northern blots demonstrated that mRNAs transcribed from this gene are present at early stages of culture. The allergen encoded by Pen c 1 gene was expressed in Escherichia coli as a fusion protein bearing an N-terminal histidine-affinity tag. The protein, purified by affinity chromatography with a yield of 130 mg of pure protein per liter of culture, was able to bind to both a monoclonal anti-Pen c 1 antibody and IgE from the serum of patients allergic to Penicillium. Recombinant Pen c 1 can therefore be expressed in E. coli in large quantities and should prove useful as a standardized specific allergen for immuno-diagnosis of atopic disorders. In addition, full caseinolytic enzyme activity could be generated in the purified recombinant protein by sulfonation and renaturation, followed by removal of the affinity tag, indicating that the refolded protein can assume the same conformation as the native protein.
Collapse
Affiliation(s)
- N Y Su
- Institute of Biochemistry, College of Medicine, National Taiwan University, Taipei, Taiwan
| | | | | | | | | |
Collapse
|
23
|
Maurer MC, Trosset JY, Lester CC, DiBella EE, Scheraga HA. New general approach for determining the solution structure of a ligand bound weakly to a receptor: structure of a fibrinogen Aalpha-like peptide bound to thrombin (S195A) obtained using NOE distance constraints and an ECEPP/3 flexible docking program. Proteins 1999; 34:29-48. [PMID: 10336381 DOI: 10.1002/(sici)1097-0134(19990101)34:1<29::aid-prot4>3.0.co;2-u] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A new approach incorporating flexible docking simulations and NMR data is presented for calculating the bound conformation of a ligand that interacts weakly with an enzyme. This approach consists of sampling directly the conformation of a flexible ligand inside a receptor active site containing surrounding flexible loops. To make this sampling efficient, a ligand-growing procedure has been adopted. Optimization of the ECEPP/3-plus-NOE constraint function is carried out by using a collective variable Monte Carlo minimization technique. Numerous energy minimizations are made possible for such a large system by using a Bezier splines energy grid technique. This new flexible docking approach was applied to determine the structure of a fibrinogen Aalpha-like peptide (7DFLAEGGGVRGPRV20) bound to an active site mutant of thrombin [thrombin(S195A)]. Structure calculations of the bound ligand, using 2D-transferred NOESY distance constraints in the DIANA program, showed that the N-terminal portion of the peptide (D7-R16) involves a chain reversal, whereas the C-terminal portion (G17-V20) adopts a fold that exists in several different orientations. In addition, the ECEPP/3 flexible docking package was used to assess the conformational variability of the ligand and surrounding 60D-insertion loop of thrombin. Amino acid residues (17-20) of the peptide interact with a region of the enzyme that exhibits broad specificity, with a preferred direction between the 60D-insertion loop and Pro37 of thrombin.
Collapse
Affiliation(s)
- M C Maurer
- Baker Laboratory of Chemistry, Cornell University, Ithaca, New York 14853-1301, USA
| | | | | | | | | |
Collapse
|
24
|
Colwell NS, Blinder MA, Tsiang M, Gibbs CS, Bock PE, Tollefsen DM. Allosteric effects of a monoclonal antibody against thrombin exosite II. Biochemistry 1998; 37:15057-65. [PMID: 9790668 DOI: 10.1021/bi980925f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We previously isolated a monoclonal antithrombin IgG from a patient with multiple myeloma [Colwell et al. (1997) Br. J. Haematol. 97, 219-226]. Using a panel of 55 surface mutants of recombinant thrombin, we now show that the epitope for the IgG most likely includes Arg-101, Arg-233, and Lys-236 in exosite II. The IgG affects the rate at which thrombin cleaves various peptide p-nitroanilide substrates with arginine in the P1 position, increasing the kcat for substrates with a P2 glycine residue but generally decreasing the kcat for substrates with a P2 proline. The allosteric effect of the IgG is altered by deletion of Pro-60b, Pro-60c, and Trp-60d from the 60-loop of thrombin, which lies between exosite II and the catalytic triad. The effect of the IgG, however, does not depend on the presence or absence of sodium ions, a known allosteric regulator of thrombin. The IgG does not affect the conformation of thrombin exosite I as determined by binding of a fluorescent derivative of hirudin54-65. These results provide evidence for a direct allosteric linkage between exosite II and the catalytic site of thrombin.
Collapse
Affiliation(s)
- N S Colwell
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | | | | | | | | | | |
Collapse
|
25
|
Zhang W, Carmichael J, Ferguson J, Inglis S, Ashrafian H, Stanley M. Expression of human papillomavirus type 16 L1 protein in Escherichia coli: denaturation, renaturation, and self-assembly of virus-like particles in vitro. Virology 1998; 243:423-31. [PMID: 9568041 DOI: 10.1006/viro.1998.9050] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Major capsid protein L1 of HPV16 was produced in a fused form in Escherichia coli using an inducible expression system. The protein formed insoluble aggregations (inclusion bodies) and the yield was more than 10% of total cell proteins. The inclusion bodies were isolated and solubilised with 8 M urea and the L1 proteins were purified by chromatographic separation. Following removal of the urea by gradual dialysis, the denatured L1 proteins spontaneously renatured and subsequently assembled into polymorphologic aggregations in vitro. Electron microscopy showed that the assembled material included structures resembling native empty capsids as well as incompletely formed capsids. After separation from the pool of polymorphologic structures by sucrose gradient sedimentation, the correctly formed virus-like particles (VLE. coliPs) were recognised by a HPV16 type-specific, conformational-dependent monoclonal antibody in an ELISA. This system offers not only a model for investigation of the intrinsic interactions that occur during L1 assembly, but also a potential route for convenient manufacture of highly purified VLP vaccines.
Collapse
Affiliation(s)
- W Zhang
- Department of Pathology, University of Cambridge, United Kingdom
| | | | | | | | | | | |
Collapse
|
26
|
Russo G, Gast A, Schlaeger EJ, Angiolillo A, Pietropaolo C. Stable expression and purification of a secreted human recombinant prethrombin-2 and its activation to thrombin. Protein Expr Purif 1997; 10:214-25. [PMID: 9226718 DOI: 10.1006/prep.1997.0733] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A human prothrombin cDNA has been engineered to obtain a cDNA coding for a secreted form of human prethrombin-2. The secreted prethrombin-2 has been produced in a mammalian expression system using DXB11 cells, a mutant strain of CHO cells in which the dihydrofolate reductase gene has been deleted, and an expression vector carrying the dihydrofolate reductase cDNA. Methotrexate-induced gene amplification favored an efficient production of the recombinant protein which accumulated in the culture medium of the DXB11 cells. Growth in suspension of the stable transformants in an airlift fermenter resulted in the production of 25 mg/L recombinant prethrombin-2. The recombinant protein was purified using single-step affinity chromatography on a recombinant-hirudin column and activated by agarose gel-immobilized ecarin. All purified recombinant prethrombin-2 was activated and the generated recombinant thrombin showed catalytic properties identical to those of plasma-derived alpha-thrombin. This expression system can be used to prepare mutants of prethrombin-2 for structure-function studies investigating thrombin interactions with substrate proteins, inhibitors, and cell membranes.
Collapse
Affiliation(s)
- G Russo
- Dipartimento di Biochimica e Biotecnologie Mediche, Università di Napoli Federico II, Italy
| | | | | | | | | |
Collapse
|
27
|
Waheed A, Pham T, Won M, Okuyama T, Sly WS. Human carbonic anhydrase IV: in vitro activation and purification of disulfide-bonded enzyme following expression in Escherichia coli. Protein Expr Purif 1997; 9:279-87. [PMID: 9056493 DOI: 10.1006/prep.1996.0691] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Human carbonic anhydrase IV (CA IV) expressed in Escherichia coli was refolded and activated in cell extracts with the help of endogenous periplasmic protein disulfide isomerase, DsbA, in the presence of oxidized glutathione. The refolding and activation were inhibited by bacitracin but not affected by known cofactors or activators of other chaperones. Although the yield of the purified CA IV recovered from cell extracts was maximal when activated at 4 degrees C in the presence of 2 mM oxidized glutathione, the rate of refolding and activation was much more rapid at 25 and 37 degrees C. The enzyme purified from the E. coli cell extracts following activation in vitro showed similar structural stability and functional properties as CA IV purified from secretion medium from a stably transfected CHO cell line. These studies suggest that the soluble truncated form of human CA IV expressed in E. coli, which is disulfide-bonded zinc metalloenzyme, can provide a useful model enzyme for studies of protein folding and enzyme activation in vitro. Furthermore, the procedure described for recovery of CA IV following expression in E. coli may be useful for in vitro activation and subsequent purification of other disulfide-containing proteins.
Collapse
Affiliation(s)
- A Waheed
- Edward A. Doisy Department of Biochemistry and Molecular Biology, St. Louis University, School of Medicine, Missouri 63104, USA
| | | | | | | | | |
Collapse
|
28
|
Staicup AM, Gahm KH, Baldueza M. Chiral separation of chloroquine using heparin as a chiral selector in high-performance liquid chromatography. Anal Chem 1996; 68:2248-50. [PMID: 9027230 DOI: 10.1021/ac951078e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The chiral selectivity of a commercially available heparin affinity column was investigated for chloroquine. The (+) enantiomer eluted first, which is consistent with results reported previously using heparin as a chiral additive in capillary zone electrophoresis. The effects of pH, ionic strength, and organic modifier on the enantiodiscrimination were explored. A combination of electrostatic and hydrophobic interactions seems to play an important role in the enantiodiscrimination exhibited by this novel phase.
Collapse
Affiliation(s)
- A M Staicup
- Department of Chemistry, University of Hawaii-Manoa, Honolulu 96822, USA
| | | | | |
Collapse
|
29
|
DiBella EE, Scheraga HA. The role of the insertion loop around tryptophan 148 in tthe activity of thrombin. Biochemistry 1996; 35:4427-33. [PMID: 8605192 DOI: 10.1021/bi952617c] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Thrombin has trypsin-like specificity for Arg-Xaa and Lys-Xaa peptide bonds; however, it is much more specific than trypsin, cleaving far fewer peptide bonds in macromolecular substrates. To probe the nature of the specificity of thrombin, a mutant has been constructed in which the Trp148 loop of thrombin has been replaced with the same loop of bovine trypsin. This mutant was expressed in Escherichia coli as prethrombin-2(148) using a T7 expression system previously described for wild-type prethrombin-2 [DiBella et al. (1995) J. Biol. Chem. 270, 163-169]. After refolding and purification, prethrombin-2(148) was activated to thrombin(148) with Echis carinatus snake venom. The k(cat)/K(m) for the release of fibrinopeptide A from fibrinogen was 4.5 +/- 0.5 microM(-1)s(-1) for thrombin(148), which was approximately 20% of that of recombinant thrombin (25 +/- 2.0 microM(-1)s(-1)). Thrombin(148) was inhibited less well by hirudin with a K(i) of 500 pM compared to a value of 12 pM determined for recombinant thrombin. The mutant thrombin was also compared to trypsin and wild-type recombinant thrombin for the ability to cleave small peptide substrates. The Michaelis constants (K(m)) were found to be between 5- and 10-fold higher for thrombin(148) relative to wild-type recombinant thrombin, although the catalytic constants (k(cat)) for thrombin(148) and recombinant thrombin remained relatively unchanged for all three substrates. Thrombin(148) had a specificity constant (k(cat)/K(m)) 2-fold higher for the hydrolysis of H-D-phenyalanyl-L- pipecolyl-L-arginine-p-nitroaniline (a thrombin substrate) than that of trypsin. For N-benzoyl-L-isoleucyl-L-glutamylglycyl-L-arginine- p-nitroaniline (a trypsin substrate) and N-carbobenzoxyglycylprolyl-L-arginine-p-nitroaniline (a substrate for both enzymes), the specificity constants for trypsin were 1000- and 16-fold higher, respectively. Although replacement of the Trp(148) loop does not yield an enzyme with more trypsin-like specificity, the Trp(148) loop is important in the substrate binding and specificity of thrombin (on the basis of K(m) and K(i)).
Collapse
Affiliation(s)
- E E DiBella
- Baker Laboratory of Chemistry, Cornell University, Ithaca, New York 14853-1301, USA
| | | |
Collapse
|