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Ignacio IF, Carmela AA, Blondy CC. Recovery of active pathogenesis-related enzymes from the apoplast of Musa acuminata infected by Mycosphaerella fijiensis. ACTA ACUST UNITED AC 2015. [DOI: 10.5897/ajb2014.14334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Barbosa EF, Monge-Fuentes V, Oliveira NB, Tavares R, Xavier MAE, Bemquerer MP, Silva LP. Protein characterisation of Brosimum gaudichaudii Trécul latex and study of nanostructured latex film formation. IET Nanobiotechnol 2014; 8:222-9. [PMID: 25429501 DOI: 10.1049/iet-nbt.2013.0042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Brosimum gaudichaudii Tréc. (Moraceae) is a common Brazilian Cerrado plant known by its pharmaceutical industry relevance. The authors investigated the latex protein components and potential biotechnological applications. Some protein fragments had their sequences elucidated, presenting similarities to jacalin and Kunitz-type trypsin inhibitors. Amino acid residue modifications were found, such as glutamine N-terminal residue cyclisation into pyroglutamic acid residue, and mass differences corresponding to hexoses and N-acetylhexosamine presence. The latex was used to produce a nanoscale structured film, which presented an increased attraction and reduced adhesion behaviours. The film presented high homogeneity, as observed by low nanoroughness values, probably because of its intrinsic components, such as the jacalin-like protein that has known agglutination properties. The immobilised Kunitz-type trypsin inhibitor presence in the latex film allow us to point out to applications related to this inhibition, as in active food packaging, since these peptidase inhibitors are able to inhibit pests and microorganism proliferation.
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Affiliation(s)
- Eduardo F Barbosa
- Postgraduate Program in Animal Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, Brazil
| | - Victoria Monge-Fuentes
- Postgraduate Program in Animal Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, Brazil
| | - Natiela B Oliveira
- Postgraduate Program in Animal Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, Brazil
| | - Rebecca Tavares
- Postgraduate Program in Animal Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, Brazil
| | - Mary-Ann E Xavier
- Postgraduate Program in Animal Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, Brazil
| | - Marcelo Porto Bemquerer
- Laboratory of Mass Spectrometry, Embrapa Genetic Resources and Biotechnology, Brasília, Brazil
| | - Luciano P Silva
- Postgraduate Program in Animal Biology, Institute of Biological Sciences, University of Brasília, UnB, Brasília, Brazil.
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Azarkan M, Matagne A, Wattiez R, Bolle L, Vandenameele J, Baeyens-Volant D. Selective and reversible thiol-pegylation, an effective approach for purification and characterization of five fully active ficin (iso)forms from Ficus carica latex. PHYTOCHEMISTRY 2011; 72:1718-1731. [PMID: 21665232 DOI: 10.1016/j.phytochem.2011.05.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Revised: 05/13/2011] [Accepted: 05/16/2011] [Indexed: 05/28/2023]
Abstract
The latex of Ficus carica constitutes an important source of many proteolytic components known under the general term of ficin (EC 3.4.22.3) which belongs to the cysteine proteases of the papain family. So far, no data on the purification and characterization of individual forms of these proteases are available. An effective strategy was used to fractionate and purify to homogeneity five ficin forms, designated A, B, C, D1 and D2 according to their sequence of elution from a cation-exchange chromatographic support. Following rapid fractionation on a SP-Sepharose Fast Flow column, the different ficin forms were chemically modified by a specific and reversible monomethoxypolyethylene glycol (mPEG) reagent. In comparison with their un-derivatized counterparts, the mPEG-protein derivatives behaved differently on the ion-exchanger, allowing us for the first time to obtain five highly purified ficin molecular species titrating 1mol of thiol group per mole of enzyme. The purified ficins were characterized by de novo peptide sequencing and peptide mass fingerprinting analyzes, using mass spectrometry. Circular dichroism measurements indicated that all five ficins were highly structured, both in term of secondary and tertiary structure. Furthermore, analysis of far-UV CD spectra allowed calculation of their secondary structural content. Both these data and the molecular masses determined by MS reinforce the view that the enzymes belong to the family of papain-like proteases. The five ficin forms also displayed different specific amidase activities against small synthetic substrates like dl-BAPNA and Boc-Ala-Ala-Gly-pNA, suggesting some differences in their active site organization. Enzymatic activity of the five ficin forms was completely inhibited by specific cysteine and cysteine/serine proteases inhibitors but was unaffected by specific serine, aspartic and metallo proteases inhibitors.
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Affiliation(s)
- Mohamed Azarkan
- Free University of Brussels, Faculty of Medicine, Protein Chemistry Unit, Campus Erasme (CP 609), 808 Route de Lennik, 1070 Brussels, Belgium.
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Lima TB, Silva ON, Migliolo L, Souza-Filho CR, Gonçalves EG, Vasconcelos IM, Oliveira JTA, Amaral AC, Franco OL. A Kunitz proteinase inhibitor from corms of Xanthosoma blandum with bactericidal activity. JOURNAL OF NATURAL PRODUCTS 2011; 74:969-975. [PMID: 21520894 DOI: 10.1021/np200312r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Bacterial infections directly affect the world's population, and this situation has been aggravated by indiscriminate use of antimicrobial agents, which can generate resistant microorganisms. In this report, an initial screening of proteins with antibacterial activity from corms of 15 species of the Xanthosoma genus was conducted. Since Xanthosoma blandum corms showed enhanced activity toward bacteria, a novel protein with bactericidal activity was isolated from this particular species. Edman degradation was used for protein N-termini determination; the primary structure showed similarities with Kunitz inhibitors, and this protein was named Xb-KTI. This protein was further challenged against serine proteinases from different sources, showing clear inhibitory activities. Otherwise, no hemolytic activity was observed for Xb-KTI. The results demonstrate the biotechnological potential of Xb-KTI, the first proteinase inhibitor with antimicrobial activity described in the Xanthosoma genus.
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Affiliation(s)
- Thaís B Lima
- Centro de Análises Proteômicas e Bioquímicas, Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, Brasília, Brazil
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Wang ZY, Ding LW, Ge ZJ, Wang Z, Wang F, Li N, Xu ZF. Purification and characterization of native and recombinant SaPIN2a, a plant sieve element-localized proteinase inhibitor. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2007; 45:757-66. [PMID: 17870592 DOI: 10.1016/j.plaphy.2007.07.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Accepted: 07/20/2007] [Indexed: 05/17/2023]
Abstract
SaPIN2a encodes a proteinase inhibitor in nightshade (Solanum americanum), which is specifically localized to the enucleate sieve elements. It has been proposed to play an important role in phloem development by regulating proteolysis in sieve elements. In this study, we purified and characterized native SaPIN2a from nightshade stems and recombinant SaPIN2a expressed in Escherichia coli. Purified native SaPIN2a was found as a charge isomer family of homodimers, and was weakly glycosylated. Native SaPIN2a significantly inhibited serine proteinases such as trypsin, chymotrypsin, and subtilisin, with the most potent inhibitory activity on subtilisin. It did not inhibit cysteine proteinase papain and aspartic proteinase cathepsin D. Recombinant SaPIN2a had a strong inhibitory effect on chymotrypsin, but its inhibitory activities toward trypsin and especially toward subtilisin were greatly reduced. In addition, native SaPIN2a can effectively inhibit midgut trypsin-like activities from Trichoplusia ni and Spodoptera litura larvae, suggesting a potential for the production of insect-resistant transgenic plants.
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Affiliation(s)
- Zhen-Yu Wang
- State Key Laboratory of Biocontrol and Key Laboratory of Gene Engineering of Ministry of Education, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
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Azarkan M, Garcia-Pino A, Dibiani R, Wyns L, Loris R, Baeyens-Volant D. Crystallization and preliminary X-ray analysis of a protease inhibitor from the latex of Carica papaya. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:1239-42. [PMID: 17142906 PMCID: PMC2225369 DOI: 10.1107/s1744309106046367] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2006] [Accepted: 11/03/2006] [Indexed: 11/10/2022]
Abstract
A Kunitz-type protease inhibitor purified from the latex of green papaya (Carica papaya) fruits was crystallized in the presence and absence of divalent metal ions. Crystal form I, which is devoid of divalent cations, diffracts to a resolution of 2.6 A and belongs to space group P3(1) or P3(2). This crystal form is a merohedral twin with two molecules in the asymmetric unit and unit-cell parameters a = b = 74.70, c = 78.97 A. Crystal form II, which was grown in the presence of Co2+, diffracts to a resolution of 1.7 A and belongs to space group P2(1)2(1)2(1), with unit-cell parameters a = 44.26, b = 81.99, c = 140.89 A.
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Affiliation(s)
- Mohamed Azarkan
- Université Libre de Bruxelles, Faculty of Medicine, Protein Chemistry Unit, Campus Erasme (CP 609), 808 Route de Lennik, B-1070 Brussels, Belgium
| | - Abel Garcia-Pino
- Department of Molecular and Cellular Interactions, Vlaams Interuniversitair Instituut voor Biotechnologie and Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Rachid Dibiani
- Université Libre de Bruxelles, Faculty of Medicine, Protein Chemistry Unit, Campus Erasme (CP 609), 808 Route de Lennik, B-1070 Brussels, Belgium
| | - Lode Wyns
- Department of Molecular and Cellular Interactions, Vlaams Interuniversitair Instituut voor Biotechnologie and Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Remy Loris
- Department of Molecular and Cellular Interactions, Vlaams Interuniversitair Instituut voor Biotechnologie and Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Danielle Baeyens-Volant
- Université Libre de Bruxelles, Faculty of Medicine, Protein Chemistry Unit, Campus Erasme (CP 609), 808 Route de Lennik, B-1070 Brussels, Belgium
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Azarkan M, Dibiani R, Goormaghtigh E, Raussens V, Baeyens-Volant D. The papaya Kunitz-type trypsin inhibitor is a highly stable beta-sheet glycoprotein. BIOCHIMICA ET BIOPHYSICA ACTA 2006; 1764:1063-72. [PMID: 16731056 DOI: 10.1016/j.bbapap.2006.02.014] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Revised: 01/27/2006] [Accepted: 02/03/2006] [Indexed: 11/16/2022]
Abstract
The papaya Kunitz-type trypsin inhibitor, a 24-kDa glycoprotein, was purified to homogeneity. The purified inhibitor stoichiometrically inhibits bovine trypsin in a 1:1 molar ratio. Circular dichroism and infrared spectroscopy analyses demonstrated that the inhibitor contains extensive beta-sheet structures. The inhibitor was found to retain its full inhibitory activity over a broad pH range (1.5-11.0) and temperature (up to 80 degrees C), besides being stable at very high concentrations of strong chemical denaturants (e.g., 5.5 M guanidine hydrochloride). The inhibitor retained its compact structure over the pH range analyzed as shown by 8-anilino-1-naphtalenesulfonic acid binding characteristics, excluding the formation of some relaxed or molten state. Exposure to 2.5 mM dithiothreitol for 120 min caused a 33% loss of the inhibitory activity, while a loss of 75% was obtained in the presence of 20 mM of dithiothreitol during the same time period. A complete loss of the inhibitory activity was observed after incubation with 50 mM dithiothreitol for 5 min. Incubation of the inhibitor with general proteases belonging to different families revealed its extraordinary resistance to proteolysis in comparison with the soybean trypsin inhibitor, the archetypal member of the Kunitz-type inhibitors family. The inhibitor also exhibited a remarkable resistance to proteolytic degradation against pepsin for at least a 24-h incubation period. Instead, the soybean inhibitor was completely degraded after 2 h incubation with this aspartic protease. All these data demonstrated the high stability of the papaya trypsin inhibitor.
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Affiliation(s)
- Mohamed Azarkan
- University of Brussels, Faculty of Medicine, Protein Chemistry Unit, Campus Erasme (CP 609), 808, route de Lennik, Bz-1070 Brussels, Belgium
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Azarkan M, Dibiani R, Baulard C, Baeyens-Volant D. Effects of mechanical wounding on Carica papaya cysteine endopeptidases accumulation and activity. Int J Biol Macromol 2006; 38:216-24. [PMID: 16580724 DOI: 10.1016/j.ijbiomac.2006.02.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 02/17/2006] [Accepted: 02/17/2006] [Indexed: 11/29/2022]
Abstract
The mechanical wounding impact on the Carica papaya latex protein pattern was investigated by analyzing three latexes. A first one commercially available, a second harvested from unripe but fully grown fruits, both obtained from regularly tapped fruits. A third one was collected from similar fruits but wounded for the first time. The results demonstrated both quantitative and qualitative changes in the protein content and in the enzymatic activity. Repeated wounding results in either, accumulation or activation (or both of them) of papain, chymopapain and caricain. Furthermore, new cysteine protease activity was found to transiently accumulate in the latex collected from newly wounded fruits. The possible implication of this enzymatic material in the papaya cysteine endopeptidases pro-forms activation is discussed.
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Affiliation(s)
- Mohamed Azarkan
- University of Brussels, Faculty of Medicine, Protein Chemistry Unit, Campus Erasme CP 609, 808, route de Lennik, B-1070 Brussels, Belgium.
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Azarkan M, El Moussaoui A, van Wuytswinkel D, Dehon G, Looze Y. Fractionation and purification of the enzymes stored in the latex of Carica papaya. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 790:229-38. [PMID: 12767335 DOI: 10.1016/s1570-0232(03)00084-9] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The latex of the tropical species Carica papaya is well known for being a rich source of the four cysteine endopeptidases papain, chymopapain, glycyl endopeptidase and caricain. Altogether, these enzymes are present in the laticifers at a concentration higher than 1 mM. The proteinases are synthesized as inactive precursors that convert into mature enzymes within 2 min after wounding the plant when the latex is abruptly expelled. Papaya latex also contains other enzymes as minor constituents. Several of these enzymes namely a class-II and a class-III chitinase, an inhibitor of serine proteinases and a glutaminyl cyclotransferase have already been purified up to apparent homogeneity and characterized. The presence of a beta-1,3-glucanase and of a cystatin is also suspected but they have not yet been isolated. Purification of these papaya enzymes calls on the use of ion-exchange supports (such as SP-Sepharose Fast Flow) and hydrophobic supports [such as Fractogel TSK Butyl 650(M), Fractogel EMD Propyl 650(S) or Thiophilic gels]. The use of covalent or affinity gels is recommended to provide preparations of cysteine endopeptidases with a high free thiol content (ideally 1 mol of essential free thiol function per mol of enzyme). The selective grafting of activated methoxypoly(ethylene glycol) chains (with M(r) of 5000) on the free thiol functions of the proteinases provides an interesting alternative to the use of covalent and affinity chromatographies especially in the case of enzymes such as chymopapain that contains, in its native state, two thiol functions.
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Affiliation(s)
- Mohamed Azarkan
- Laboratoire de Chimie Générale, Unité de Chimie des Protéines (CP 609), Faculté de Médecine, Université Libre de Bruxelles, Campus Erasme, 808 Route de Lennik, B-1070, Brussels, Belgium
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Valueva TA, Revina TA, Mosolov VV, Mentele R. Primary structure of potato kunitz-type serine proteinase inhibitor. Biol Chem 2000; 381:1215-21. [PMID: 11209756 DOI: 10.1515/bc.2000.149] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The serine proteinase inhibitor (PSPI-21) isolated from potato tubers (Solanum tuberosum L.) comprises two protein species with pI 5.2 and 6.3, denoted as PSPI-21-5.2 and PSPI-21-6.3, respectively. They were separated by anion exchange chromatography on a Mono Q FPLC column. Both species tightly inhibit human leukocyte elastase, whereas their interaction with trypsin and chymotrypsin is substantially weaker. The sequences of both PSPI-21-5.2 and PSPI-21-6.3 were determined by analysis of overlapping peptides obtained from the oxidized or reduced and S-pyridylethylated proteins after digestion with trypsin or pepsin. Both species of PSPI-21 are composed of two chains, named chains A and B, which are linked by a disulfide bridge between Cys(146) and Cys(157). The other disulfide bridge is located within the A chains between Cys(48) and Cys(97). The amino acid sequences of the large A chains of the two forms, consisting of 150 amino acids residues each, differ in a single residue at position 52. The small chains B, containing 37 and 36 residues in PSPI-21-6.3 and PSPI-21-5.2, respectively, have nine different residues. The entire amino acid sequences of the two inhibitors show a high degree of homology to the other Kunitz-type proteinase inhibitors from plants.
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Affiliation(s)
- T A Valueva
- Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow
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Kochhar S, Gartenmann K, Juillerat MA. Primary structure of the abundant seed albumin of Theobroma cacao by mass spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2000; 48:5593-5599. [PMID: 11087524 DOI: 10.1021/jf0006067] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The most abundant albumin present in seeds of Theobroma cacao was purified to apparent homogeneity as judged by high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS), sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and NH(2)-terminal sequence analysis. Tryptic peptide mass fingerprinting of the purified protein by HPLC/ESI-MS showed the presence of 16 masses that matched the expected tryptic peptides corresponding to 95% of the translated amino acid sequence from the cDNA of the 21 kDa cocoa albumin. Collision-induced dissociation MS/MS analysis of the C-terminal peptide isolated from the CNBr cleavage products provided unequivocal evidence that the mature cocoa albumin protein is nine amino acid residues shorter than expected from the reported cDNA of its corresponding gene. The experimentally determined M(r) value of 20234 was in excellent agreement with the truncated version of the amino acid sequence. The purified cocoa albumin inhibited the catalytic activities of bovine trypsin and chymotrypsin. The inhibition was stoichiometric with 1 mol of trypsin or chymotrypsin being inhibited by 1 mol of inhibitor with apparent dissociation constants (K(i)) of 9.5 x 10(-8) and 2. 3 x 10(-6) M, respectively, for inhibitor binding at pH 8.5 and 37 degrees C. No inhibition of the catalytic activities of subtilisin, papain, pepsin, and cocoa endoproteases was detected under their optimal reaction conditions.
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Affiliation(s)
- S Kochhar
- Nestlé Research Center, P.O. Box 44, Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland.
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Abstract
Due to the limited resources for the management of burns in most regions of Africa there is a significant role for many aspects of traditional African medicine. The active component of many traditional preparations is often of plant origin and more than 25 plants have been described as useful in relations to burns and wound healing. Carica papaya is currently used in The Gambia at the Royal Victoria Hospital, Banjul in the Paediatric Unit as the major component of burns dressings, where it is well tolerated by the children. Cheap and widely available, the pulp of the papaya fruit is mashed and applied daily to full thickness and infected burns. It appears to be effective in desloughing necrotic tissue, preventing burn wound infection, and providing a granulating wound suitable for the application of a split thickness skin graft. Possible mechanisms of action include the activity of proteolytic enzymes chymopapain and papain, as well as an antimicrobial activity, although further studies are required.
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Affiliation(s)
- I F Starley
- The Royal Preston Hospital, Preston, Lancashire, UK
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Zerhouni S, Amrani A, Nijs M, Smolders N, Azarkan M, Vincentelli J, Looze Y. Purification and characterization of papaya glutamine cyclotransferase, a plant enzyme highly resistant to chemical, acid and thermal denaturation. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1387:275-90. [PMID: 9748628 DOI: 10.1016/s0167-4838(98)00140-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Papaya glutamine cyclotransferase (PQC), present in the laticiferous cells of the tropical species Carica papaya, was purified near to homogeneity. Starting from the soluble fraction of the collected plant latex, a combination of ion-exchange chromatography on SP-Sepharose Fast Flow, hydrophobic interaction chromatography on Fractogel TSK Butyl-650 and affinity chromatography on immobilized trypsin provided a purification factor of 279 with an overall yield of 80%. In the course of the purification procedure, the two solvent accessible thiol functions located on the hydrophobic surface of the enzyme were converted into their S-methylthioderivatives. Papaya QC, a glycoprotein with a molecular mass of 33000 Da, contains a unique and highly basic polypeptide chain devoid of disulfide bridges as well as of covalently attached phosphate groups. Its absorption spectrum is dominated by the chromophores tyrosine which, nonetheless, do not contribute to the fluorescence emission of the plant enzyme. With a lambdamax of emission at 338 nm and a moderate susceptibility to be quenched by acrylamide, most of the tryptophyl residues of papaya QC appear to be sterically shielded by surrounding protein atoms. Fluorescence can thus be used to monitor unfolding of this enzyme. Preliminary experiments show that papaya QC is exceptionally resistant to chemical (guanidinium hydrochloride), acid and thermal denaturation. At first sight also, this enzyme exhibits high resistance to proteolysis by the papaya cysteine proteinases, yet present in great excess (around 100 mol of proteinases per mol of PQC) in the plant latex. Altogether, these results awaken much curiosity and interest to further investigate how the structure of this plant enzyme is specified.
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Affiliation(s)
- S Zerhouni
- Protein Chemistry Department (CP 609), Faculty of Medicine, Free University of Brussels, Campus Erasme, Route de Lennik, 808, B-1070 Brussels, Belgium
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Sugimoto H, Odani S, Yamashita S. Cloning and expression of cDNA encoding rat liver 60-kDa lysophospholipase containing an asparaginase-like region and ankyrin repeat. J Biol Chem 1998; 273:12536-42. [PMID: 9575212 DOI: 10.1074/jbc.273.20.12536] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mammalian tissues contain small form and large form lysophospholipases. Here we report the cloning, sequence, and expression of cDNA encoding the latter form of lysophospholipase using antibody raised against the enzyme purified from rat liver supernatant (Sugimoto, H., and Yamashita, S. (1994) J. Biol. Chem. 269, 6252-6258). The 2,539-base pair cDNA encoded 564 amino acid residues with a calculated Mr of 60,794. The amino-terminal two-thirds of the deduced amino acid sequence significantly resembled Escherichia coli asparaginase I with the putative asparaginase catalytic triad Thr-Asp-Lys and was followed by leucine zipper motif. The carboxyl-terminal region carried ankyrin repeat. When the cDNA was transfected into HEK293 cells, not only lysophospholipase activity but also asparaginase and platelet-activating factor acetylhydrolase activities were expressed. Reverse transcription-polymerase chain reaction revealed that the transcript occurred at high levels in liver and kidney but was hardly detectable in lung and heart from which large form lysophospholipases had been purified, suggesting the presence of multiple forms of large form lysophospholipase in mammalian tissues.
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Affiliation(s)
- H Sugimoto
- Department of Biochemistry, Gunma University School of Medicine, Maebashi 371-8511, Japan
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