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Mlayah-Bellalouna S, Aissaoui-Zid D, Chantome A, Jebali J, Souid S, Ayedi E, Mejdoub H, Belghazi M, Marrakchi N, Essafi-Benkhadir K, Vandier C, Srairi-Abid N. Insights into the mechanisms governing P01 scorpion toxin effect against U87 glioblastoma cells oncogenesis. Front Pharmacol 2023; 14:1203247. [PMID: 37426811 PMCID: PMC10326281 DOI: 10.3389/fphar.2023.1203247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 06/12/2023] [Indexed: 07/11/2023] Open
Abstract
The emerging concept of small conductance Ca2+-activated potassium channels (SKCa) as pharmacological target for cancer treatment has significantly increased in recent years. In this study, we isolated the P01 toxin from Androctonus australis (Aa) scorpion venom and investigated its effect on biological properties of glioblastoma U87, breast MDA-MB231 and colon adenocarcinoma LS174 cancer cell lines. Our results showed that P01 was active only on U87 glioblastoma cells. It inhibited their proliferation, adhesion and migration with IC50 values in the micromolar range. We have also shown that P01 reduced the amplitude of the currents recorded in HEK293 cells expressing SK2 channels with an IC50 value of 3 pM, while it had no effect on those expressing SK3 channels. The investigation of the SKCa channels expression pattern showed that SK2 transcripts were expressed differently in the three cancer cell lines. Particularly, we highlighted the presence of SK2 isoforms in U87 cells, which could explain and rely on the specific activity of P01 on this cell line. These experimental data highlighted the usefulness of scorpion peptides to decipher the role of SKCa channels in the tumorigenesis process, and develop potential therapeutic molecules targeting glioblastoma with high selectivity.
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Affiliation(s)
- Saoussen Mlayah-Bellalouna
- LR20IPT01 Biomolécules, Venins et Application Théranostique, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Dorra Aissaoui-Zid
- LR20IPT01 Biomolécules, Venins et Application Théranostique, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Aurelie Chantome
- N2C UMR 1069, Institut national de la santé et de la recherche médicale, University of Tours, Tours, France
| | - Jed Jebali
- LR20IPT01 Biomolécules, Venins et Application Théranostique, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Soumaya Souid
- LR16IPT04 Laboratoire d’Epidémiologie Moléculaire et Pathologie Expérimentale, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Emna Ayedi
- LR20IPT01 Biomolécules, Venins et Application Théranostique, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Hafedh Mejdoub
- USCR Séquenceur de Protéines, Faculté des Sciences de Sfax, Route de Soukra, Sfax, Tunisia
| | - Maya Belghazi
- Aix Marseille Université, CNRS, Plateforme Protéomique, IMM FR3479, Marseille Protéomique (MaP), Marseille, France
| | - Naziha Marrakchi
- LR20IPT01 Biomolécules, Venins et Application Théranostique, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Khadija Essafi-Benkhadir
- LR16IPT04 Laboratoire d’Epidémiologie Moléculaire et Pathologie Expérimentale, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Christophe Vandier
- N2C UMR 1069, Institut national de la santé et de la recherche médicale, University of Tours, Tours, France
| | - Najet Srairi-Abid
- LR20IPT01 Biomolécules, Venins et Application Théranostique, Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis, Tunisia
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Chaâbene Z, Rorat A, Kriaa W, Rekik I, Mejdoub H, Vandenbulcke F, Elleuch A. In-site and Ex-site Date Palm Exposure to Heavy Metals Involved Infra-Individual Biomarkers Upregulation. Plants (Basel) 2021; 10:plants10010137. [PMID: 33445405 PMCID: PMC7826821 DOI: 10.3390/plants10010137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/29/2020] [Accepted: 01/06/2021] [Indexed: 11/16/2022]
Abstract
As a tree of considerable importance in arid regions-date palm, Phoenix dactylifera L. survival in contaminated areas of Sfax city has drawn our attention. Leaf samples of the plants grown in the study area showed high levels of cadmium (Cd), copper (Cu), and chromium (Cr). On the basis of this finding, the cellular mechanisms that explain these metal accumulations were investigated in controlled conditions. After four months of exposure to Cd, Cr, or Cu, high bioconcentration and translocation factor (TF>1) have been shown for date palm plantlets exposed to Cd and low TF values were obtained for plantlets treated with Cr and Cu. Moreover, accumulation of oxidants and antioxidant enzyme activities occurred in exposed roots to Cu and Cd. Secondary metabolites, such as polyphenols and flavonoids, were enhanced in plants exposed at low metal concentrations and declined thereafter. Accumulation of flavonoids in cells may be correlated with the expression of the gene encoding Pdmate5, responsible for the transport of secondary metabolites, especially flavonoids. Other transporter genes responded positively to metal incorporation, especially Pdhma2, but also Pdabcc and Pdnramp6. The latter would be a new candidate gene sensitive to metallic stress in plants. Expressions of gene coding metal chelators were also investigated. Pdpcs1 and Pdmt3 exhibited a strong induction in plants exposed to Cr. These modifications of the expression of some biochemical and molecular based-markers in date palm helped to better understand the ability of the plant to tolerate metals. They could be useful in assessing heavy metal contaminations in polluted soils and may improve accumulation capacity of other plants.
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Affiliation(s)
- Zayneb Chaâbene
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax 3000, Tunisia; (H.M.); (A.E.)
- Laboratoire de Génie Civil et géo-Environnement–Université de Lille 1, F-59655 Villeneuve d’Ascq, France; (A.R.); (F.V.)
- Correspondence:
| | - Agnieszka Rorat
- Laboratoire de Génie Civil et géo-Environnement–Université de Lille 1, F-59655 Villeneuve d’Ascq, France; (A.R.); (F.V.)
| | - Walid Kriaa
- Environmental Science Center, Qatar University, Doha P.O. Box 2713, Qatar;
| | - Imen Rekik
- High Institute of Applied Biology of Medenine, Medenine 4119, Tunisia;
| | - Hafedh Mejdoub
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax 3000, Tunisia; (H.M.); (A.E.)
| | - Franck Vandenbulcke
- Laboratoire de Génie Civil et géo-Environnement–Université de Lille 1, F-59655 Villeneuve d’Ascq, France; (A.R.); (F.V.)
| | - Amine Elleuch
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax 3000, Tunisia; (H.M.); (A.E.)
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Ghanmi F, Carré-Mlouka A, Zarai Z, Mejdoub H, Peduzzi J, Maalej S, Rebuffat S. The extremely halophilic archaeon Halobacterium salinarum ETD5 from the solar saltern of Sfax (Tunisia) produces multiple halocins. Res Microbiol 2019; 171:80-90. [PMID: 31560985 DOI: 10.1016/j.resmic.2019.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/09/2019] [Accepted: 09/17/2019] [Indexed: 10/26/2022]
Abstract
The extremely halophilic archaeon Halobacterium salinarum strain ETD5 was previously isolated from the solar saltern of Sfax (Tunisia) and shown to encode and express halocin S8. The Hbt. salinarum ETD5 culture supernatant was shown here to exhibit high antimicrobial activity against several halophilic archaea and bacteria of different genera, showing a cross-domain inhibition. The antimicrobial activity was destroyed by proteases, thus pointing to halocins. A bioguided purification procedure was applied using two chromatography steps and antimicrobial assays directed against Halorubrum chaoviator ETR14. In-gel screening assay showed the presence of two antimicrobial bands of approximately 8 and 14 kDa, for which characterization was investigated by N-terminal sequencing and mass spectrometry. The full-length form of halocin S8 that contains 81 amino acids and differs from the 36 amino acid short-length halocin S8 previously described from an uncharacterized haloarchaeon S8a, was identified in the 8 kDa halocin band. A novel halocin that we termed halocin S14 was found in the 14 kDa band. It exhibits amino acid sequence identities with the N-terminally truncated region of the archaeal Mn-superoxide dismutase. These results show that Hbt. salinarum ETD5 produces multiple halocins, a feature that had not been described until now in the domain Archaea.
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Affiliation(s)
- Fadoua Ghanmi
- Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM) UMR 7245 CNRS-MNHN, Muséum national d'Histoire naturelle, Centre national de la Recherche scientifique (CNRS), CP 54, 57 rue Cuvier, 75005, Paris, France; Laboratory of Biodiversity and Aquatic Ecosystems, Ecology and Planktonology, University of Sfax-Tunisia, Faculty of Sciences, BP 1171, Tunisia.
| | - Alyssa Carré-Mlouka
- Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM) UMR 7245 CNRS-MNHN, Muséum national d'Histoire naturelle, Centre national de la Recherche scientifique (CNRS), CP 54, 57 rue Cuvier, 75005, Paris, France.
| | - Zied Zarai
- Laboratory of Plant Biotechnology, Sfax Faculty of Sciences, University of Sfax-Tunisia, Faculty of Sciences, BP 1171, Tunisia.
| | - Hafedh Mejdoub
- Laboratory of Plant Biotechnology, Sfax Faculty of Sciences, University of Sfax-Tunisia, Faculty of Sciences, BP 1171, Tunisia.
| | - Jean Peduzzi
- Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM) UMR 7245 CNRS-MNHN, Muséum national d'Histoire naturelle, Centre national de la Recherche scientifique (CNRS), CP 54, 57 rue Cuvier, 75005, Paris, France.
| | - Sami Maalej
- Laboratory of Biodiversity and Aquatic Ecosystems, Ecology and Planktonology, University of Sfax-Tunisia, Faculty of Sciences, BP 1171, Tunisia.
| | - Sylvie Rebuffat
- Laboratory Molecules of Communication and Adaptation of Microorganisms (MCAM) UMR 7245 CNRS-MNHN, Muséum national d'Histoire naturelle, Centre national de la Recherche scientifique (CNRS), CP 54, 57 rue Cuvier, 75005, Paris, France.
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Chaâbene Z, Rorat A, Rekik Hakim I, Bernard F, Douglas GC, Elleuch A, Vandenbulcke F, Mejdoub H. Insight into the expression variation of metal-responsive genes in the seedling of date palm (Phoenix dactylifera). Chemosphere 2018; 197:123-134. [PMID: 29334652 DOI: 10.1016/j.chemosphere.2017.12.146] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Revised: 12/20/2017] [Accepted: 12/22/2017] [Indexed: 05/27/2023]
Abstract
Phytochelatin synthase and metallothionein gene expressions were monitored via qPCR in order to investigate the molecular mechanisms involved in Cd and Cr detoxification in date palm (Phoenix dactylifera). A specific reference gene validation procedure using BestKeeper, NormFinder and geNorm programs allowed selection of the three most stable reference genes in a context of Cd or Cr contamination among six reference gene candidates, namely elongation factor α1, actin, aldehyde dehydrogenase, SAND family, tubulin 6 and TaTa box binding protein. Phytochelatin synthase (pcs) and metallothionein (mt) encoding gene expression were induced from the first days of exposure. At low Cd stress (0.02 mM), genes were still up-regulated until 60th day of exposure. At the highest metal concentrations, however, pcs and mt gene expressions decreased. pcs encoding gene was significantly up-regulated under Cr exposure, and was more responsive to increasing Cr concentration than mt encoding gene. Moreover, exposure to Cd or Cr influenced clearly seed germination and hypocotyls elongation. Thus, the results have proved that both analyzed genes participate in metal detoxification and their expression is regulated at transcriptional level in date palm subjected to Cr and Cd stress. Consequently, variations of expression of mt and pcs genes may serve as early-warning biomarkers of metal stress in this species.
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Affiliation(s)
- Zayneb Chaâbene
- Laboratory of Plant Biotechnology, Faculty of Sciences, BP 1171, 3000 Sfax, University of Sfax, Tunisia; Laboratoire de Génie Civil et géo-Environnement, Université de Lille 1, F-59655 Villeneuve d'Ascq, France
| | - Agnieszka Rorat
- Laboratoire de Génie Civil et géo-Environnement, Université de Lille 1, F-59655 Villeneuve d'Ascq, France.
| | - Imen Rekik Hakim
- Laboratory of Plant Biotechnology, Faculty of Sciences, BP 1171, 3000 Sfax, University of Sfax, Tunisia
| | - Fabien Bernard
- Laboratoire de Génie Civil et géo-Environnement, Université de Lille 1, F-59655 Villeneuve d'Ascq, France
| | - Grubb C Douglas
- Biorecycling Operations Research Laboratory, Des Moines, Iowa, USA
| | - Amine Elleuch
- Laboratory of Plant Biotechnology, Faculty of Sciences, BP 1171, 3000 Sfax, University of Sfax, Tunisia
| | - Franck Vandenbulcke
- Laboratoire de Génie Civil et géo-Environnement, Université de Lille 1, F-59655 Villeneuve d'Ascq, France
| | - Hafedh Mejdoub
- Laboratory of Plant Biotechnology, Faculty of Sciences, BP 1171, 3000 Sfax, University of Sfax, Tunisia
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Chaâbene Z, Hakim IR, Rorat A, Elleuch A, Mejdoub H, Vandenbulcke F. Copper toxicity and date palm (Phoenix dactylifera) seedling tolerance: Monitoring of related biomarkers. Environ Toxicol Chem 2018; 37:797-806. [PMID: 29023967 DOI: 10.1002/etc.4007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 04/24/2017] [Accepted: 10/11/2017] [Indexed: 06/07/2023]
Abstract
Date palm (Phoenix dactylifera) seeds were exposed to different copper (Cu) solutions to examine plant stress responses. Low Cu concentrations (0.02 and 0.2 mM) caused an increase of seed germination, whereas higher Cu amounts (2 mM) significantly inhibited seed germination, delayed hypocotyl elongation, increased seedling mortality, and reduced the germination index by more than 90%. Metal-related toxicity symptoms appeared after 15 d of 2 mM of Cu exposure. Biochemical activities such as amylase activity and redox balance elements were examined to study the relationship between external Cu amount and internal plant response. The present study showed that amylolytic activity was dose- and time-dependent. Likewise, H2 O2 production increased after exposure to Cu, which was correlated with thiobarbituric acid reactive substance (TBARS) accumulation. Furthermore at low Cu concentrations, superoxide dismutase (SOD) and catalase (CAT) activities increased, suggesting that date palm seed stimulated its metal homeostasis networks. However, the highest cupric ion amounts increased cell oxidant accumulation and reduced enzyme production. Gene expression level measures of P. dactylifera phytochelatin synthase (Pdpcs) and P. dactylifera metallothionein (Pdmt) encoding genes have been carried out to investigate the implication of PdPCS and PdMT proteins in Cu homeostasis and/or its sequestration. Phoenix dactylifera metallothionein induction reached a peak after 30 d of exposure to 0.2 mM of Cu. However, it was down-regulated in plants exposed to higher Cu concentrations. In the same conditions, Pdpcs was overexpressed during 1 mo of exposure before it decreased thereafter. These observations provide a new insight into date palm cell response to Cu, a metal that can be toxic but that is also an essential element. Environ Toxicol Chem 2018;37:797-806. © 2017 SETAC.
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Affiliation(s)
- Zayneb Chaâbene
- Laboratory of Plant Biotechnology, Faculty of Sciences, University of Sfax, Sfax, Tunisia
- Laboratoire de Génie Civil et géo-Environnement, Université de Lille, Villeneuve d'Ascq, Lille, France
| | - Imen Rekik Hakim
- Laboratory of Plant Biotechnology, Faculty of Sciences, University of Sfax, Sfax, Tunisia
| | - Agnieszka Rorat
- Laboratoire de Génie Civil et géo-Environnement, Université de Lille, Villeneuve d'Ascq, Lille, France
| | - Amine Elleuch
- Laboratoire de Génie Civil et géo-Environnement, Université de Lille, Villeneuve d'Ascq, Lille, France
| | - Hafedh Mejdoub
- Laboratoire de Génie Civil et géo-Environnement, Université de Lille, Villeneuve d'Ascq, Lille, France
| | - Franck Vandenbulcke
- Laboratoire de Génie Civil et géo-Environnement, Université de Lille, Villeneuve d'Ascq, Lille, France
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El Abed H, Khemakhem B, Fendri I, Chakroun M, Triki M, Drira N, Mejdoub H. Extraction, partial purification and characterization of amylase from parthenocarpic date (Phoenix dactylifera): effect on cake quality. J Sci Food Agric 2017; 97:3445-3452. [PMID: 28070892 DOI: 10.1002/jsfa.8198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 12/30/2016] [Accepted: 12/31/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Phoenix dactylifera L. plays an important role in social, economic and ecological Tunisian sectors. Some date palms produce parthenocarpic fruit named Sish. The objective of the present study was to extract biomolecules from parthenocarpic fruit by producing value-added products from the fruits. RESULTS The extraction of amylolytic activity from parthenocarpic fruit (AmyPF) was optimized using Box-Behnken design (BBD). Partial purification of about 250-fold with an activity yield of 47% was achieved. The amylase exhibited a specific activity of 80 U mg-1 protein. The optimum pH and temperature for enzyme activity were 5 and 55 °C respectively. The enzyme was highly active over a wide range of pH (5-10), and significant stabilization was observed at 60 °C. The purified enzyme belongs to the exo type of amylases. Given the economic and industrial relevance of amylases used in the food industry, three different concentrations of AmyPF (0.007, 0.014 and 0.018 U g-1 ) were incorporated into a cake formulation, resulting in a decrease in density, moisture retention and water activity and an increase in hardness. CONCLUSION The beneficial effect of AmyPF on the technological characteristics of cakes was confirmed by sensory evaluation. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Hanen El Abed
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
| | - Bassem Khemakhem
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
| | - Imen Fendri
- Laboratory of Toxicology, Environmental Microbiology and Health, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
| | - Mouna Chakroun
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
| | - Mehdi Triki
- Food Analysis Laboratory, National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia
| | - Noureddine Drira
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
| | - Hafedh Mejdoub
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
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Frikha Dammak D, Zarai Z, Najah S, Abdennabi R, Belbahri L, Rateb ME, Mejdoub H, Maalej S. Antagonistic Properties of Some Halophilic Thermoactinomycetes Isolated from Superficial Sediment of a Solar Saltern and Production of Cyclic Antimicrobial Peptides by the Novel Isolate Paludifilum halophilum. Biomed Res Int 2017; 2017:1205258. [PMID: 28819625 PMCID: PMC5551467 DOI: 10.1155/2017/1205258] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 06/18/2017] [Indexed: 02/07/2023]
Abstract
This study has focused on the isolation of twenty-three halophilic actinomycetes from two ponds of different salinity and the evaluation of their ability to exert an antimicrobial activity against both their competitors and several other pathogens. From the 23 isolates, 18 strains showed antagonistic activity, while 19 showed activities against one or more of the seven pathogen strains tested. Six strains exhibited consistent antibacterial activity against Gram-negative and Gram-positive pathogens characterized at the physiological and molecular levels. These strains shared only 94-95% 16S rRNA sequence identity with the closely related species of the Thermoactinomycetaceae family. Among them, the potent strain SMBg3 was further characterized and assigned to a new genus in the family for which the name Paludifilum halophilum (DSM 102817T) is proposed. Sequential extraction of the antimicrobial compounds with ethyl acetate revealed that the crude extract from SMBg3 strain had inhibitory effect on the growth of the plant pathogen Agrobacterium tumefaciens and the human pathogens Staphylococcus aureus, Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa. Based on the HRESI-MS spectral data, the cyclic lipopeptide Gramicidin S and four cyclic dipeptides (CDPs) named cyclo(L-4-OH-Pro-L-Leu), cyclo(L-Tyr-L-Pro), cyclo(L-Phe-L-Pro), and cyclo(L-Leu-L-Pro) were detected in the fermentation broth of Paludifilum halophilum. To our knowledge, this is the first report on the isolation of these compounds from members of the Thermoactinomycetaceae family.
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Affiliation(s)
- Donyez Frikha Dammak
- Unité Biodiversité et Ecosystèmes Aquatiques Environnementaux (UR/11ES/72), Faculté des Sciences de Sfax, Université de Sfax, BP 1171, 3000 Sfax, Tunisia
| | - Ziad Zarai
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS, BPW, 1173 Sfax, Tunisia
| | - Soumaya Najah
- Institut de Biologie Integrative, UMR 9198, Université Paris-Sud, Bat 400, 91405 Orsay Cedex, France
| | - Rayed Abdennabi
- Laboratory of Soil Biology, University of Neuchatel, 11 Rue Emile Argand, 2000 Neuchatel, Switzerland
| | - Lassaad Belbahri
- Laboratory of Soil Biology, University of Neuchatel, 11 Rue Emile Argand, 2000 Neuchatel, Switzerland
| | - Mostafa E. Rateb
- School of Science & Sport, University of the West of Scotland, Paisley PA1 2BE, UK
| | - Hafedh Mejdoub
- Laboratoire des Biotechnologies Végétales Appliquées à l'Amélioration des Cultures, FSS, Université de Sfax, BP 1171, 3000 Sfax, Tunisia
| | - Sami Maalej
- Unité Biodiversité et Ecosystèmes Aquatiques Environnementaux (UR/11ES/72), Faculté des Sciences de Sfax, Université de Sfax, BP 1171, 3000 Sfax, Tunisia
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Nasri R, Hassen Zrour S, Rebai H, Neffeti F, Najjar MF, Bergaoui N, Mejdoub H, Tabka Z. Combat sports practice favors bone mineral density among adolescent male athletes. J Clin Densitom 2015; 18:54-9. [PMID: 24176431 DOI: 10.1016/j.jocd.2013.09.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 08/08/2013] [Accepted: 09/11/2013] [Indexed: 12/30/2022]
Abstract
The aim of this study was to determine the impact of combat sports practice on bone mineral density (BMD) and to analyze the relationship between bone parameters and anthropometric measurements, bone markers, and activity index (AI). In other words, to detect the most important determinant of BMD in the adolescent period among combat sports athletes. Fifty athletes engaged in combat sports, mean age 17.1±0.2 yr, were compared with 30 sedentary subjects who were matched for age, height, and pubertal stage. For all subjects, the whole-body BMD, lumbar spine BMD (L2-L4), and BMD in the pelvis, arms, and legs was measured by dual-energy X-ray absorptiometry, and anthropometric measurements were evaluated. Daily calcium intake, bone resorption, and formation markers were measured. BMD measurements were greater in the combat sports athletes than in the sedentary group (p<0.01). Weight, body mass index, and lean body mass were significantly correlated with BMD in different sites. Daily calcium consumption lower than daily calcium intake recommended in both athletes and sedentary group. AI was strongly correlated with all BMD measurements particularly with the whole body, legs, and arms. Negative correlations were observed between bone markers and BMD in different sites. The common major predictor of BMD measurements was AI (p<0.0001). AI associated to lean body mass determined whole-body BMD until 74%. AI explained both BMD in arms and L2-L4 at 25%. AI associated to height can account for 63% of the variance in BMD legs. These observations suggested that the best model predicting BMD in different sites among adolescent combat sports athletes was the AI. Children and adolescents should be encouraged to participate in combat sports to maximize their bone accrual.
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Affiliation(s)
- Raouf Nasri
- Laboratory of Physiology and Functional Explorations, Faculty of Medicine Ibn El Jazzar of Sousse, University of Sousse, Sousse, Tunisia.
| | | | - Haithem Rebai
- Laboratory of Physiology and Functional Explorations, Faculty of Medicine Ibn El Jazzar of Sousse, University of Sousse, Sousse, Tunisia
| | - Fadoua Neffeti
- Biochemistry and Toxicology Laboratory, Monastir Teaching Hospital, Monastir, Tunisia
| | - Mohamed Fadhel Najjar
- Biochemistry and Toxicology Laboratory, Monastir Teaching Hospital, Monastir, Tunisia
| | - Naceur Bergaoui
- Rheumatology Department, Monastir Teaching Hospital, Monastir, Tunisia
| | - Hafedh Mejdoub
- Research Laboratory of Protein Sequencer, Faculty of Sciences, University of Sfax, Sfax, Tunisia
| | - Zouhair Tabka
- Laboratory of Physiology and Functional Explorations, Faculty of Medicine Ibn El Jazzar of Sousse, University of Sousse, Sousse, Tunisia
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Mlayah-Bellalouna S, Dufour M, Mabrouk K, Mejdoub H, Carlier E, Othman H, Belghazi M, Tarbe M, Goaillard JM, Gigmes D, Seagar M, El Ayeb M, Debanne D, Srairi-Abid N. AaTX1, from Androctonus australis scorpion venom: purification, synthesis and characterization in dopaminergic neurons. Toxicon 2014; 92:14-23. [PMID: 25240295 DOI: 10.1016/j.toxicon.2014.09.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/21/2014] [Accepted: 09/09/2014] [Indexed: 10/24/2022]
Abstract
We have purified the AaTX1 peptide from the Androctonus australis (Aa) scorpion venom, previously cloned and sequenced by Legros and collaborators in a venom gland cDNA library from Aa scorpion. AaTX1 belongs to the α-Ktx15 scorpion toxins family (αKTx15-4). Characterized members of this family share high sequence similarity and were found to block preferentially IA-type voltage-dependent K(+) currents in rat cerebellum granular cells in an irreversible way. In the current work, we studied the effects of native AaTX1 (nAaTX1) using whole-cell patch-clamp recordings of IA current in substantia nigra pars compacta dopaminergic neurons. At 250 nM, AaTX1 induces 90% decrease in IA current amplitude. Its activity was found to be comparable to that of rAmmTX3 (αKTx15-3), which differs by only one conserved (R/K) amino acid in the 19th position suggesting that the difference between R19 and K19 in AaTX1 and AmmTX3, respectively, may not be critical for the toxins' effects. Molecular docking of both toxins with Kv4.3 channel is in agreement with experimental data and suggests the implication of the functional dyade K27-Y36 in toxin-channel interactions. Since AaTX1 is not highly abundant in Aa venom, it was synthesized as well as AmmTX3. Synthetic peptides, native AaTX1 and rAmmTX3 peptides showed qualitatively the same pharmacological activity. Overall, these data identify a new biologically active toxin that belongs to a family of peptides active on Kv4.3 channel.
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Affiliation(s)
- Saoussen Mlayah-Bellalouna
- Institut Pasteur de Tunis, Laboratoire des Venins et biomolécules thérapeutiques LR11IPT08, Tunis 1002, Tunisia
| | - Martial Dufour
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse (UNIS), Faculté de Médecine - Secteur Nord, Aix Marseille Université, 51, Bd Pierre Dramard, 13015 Marseille, France
| | - Kamel Mabrouk
- Aix Marseille Université, Institut de Chimie Radicalaire ICR, UMR 7273, Equipe CROPS, Site St Jérôme, Avenue Escadrille Normandie Niémen, Case 542, 13397 Marseille Cedex 20, France
| | - Hafedh Mejdoub
- USCR séquenceur de protéines, faculté des sciences de Sfax, Route de Soukra, Km 3.5, BP 1171, 3000 Sfax, Tunisia
| | - Edmond Carlier
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse (UNIS), Faculté de Médecine - Secteur Nord, Aix Marseille Université, 51, Bd Pierre Dramard, 13015 Marseille, France
| | - Houcemeddine Othman
- Institut Pasteur de Tunis, Laboratoire des Venins et biomolécules thérapeutiques LR11IPT08, Tunis 1002, Tunisia
| | - Maya Belghazi
- CRN2M UMR 7286, Plate Forme de Recherche en Neurosciences - CAPM, Faculté de Médecine-secteur Nord Aix Marseille Université, 51 bd Pierre Dramard, 13015 Marseille, France
| | - Marion Tarbe
- Aix Marseille Université, Institut de Chimie Radicalaire ICR, UMR 7273, Equipe CROPS, Site St Jérôme, Avenue Escadrille Normandie Niémen, Case 542, 13397 Marseille Cedex 20, France
| | - Jean Marc Goaillard
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse (UNIS), Faculté de Médecine - Secteur Nord, Aix Marseille Université, 51, Bd Pierre Dramard, 13015 Marseille, France
| | - Didier Gigmes
- Aix Marseille Université, Institut de Chimie Radicalaire ICR, UMR 7273, Equipe CROPS, Site St Jérôme, Avenue Escadrille Normandie Niémen, Case 542, 13397 Marseille Cedex 20, France
| | - Michael Seagar
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse (UNIS), Faculté de Médecine - Secteur Nord, Aix Marseille Université, 51, Bd Pierre Dramard, 13015 Marseille, France
| | - Mohamed El Ayeb
- Institut Pasteur de Tunis, Laboratoire des Venins et biomolécules thérapeutiques LR11IPT08, Tunis 1002, Tunisia
| | - Dominique Debanne
- INSERM UMR_S 1072, Unité de Neurobiologie des canaux Ioniques et de la Synapse (UNIS), Faculté de Médecine - Secteur Nord, Aix Marseille Université, 51, Bd Pierre Dramard, 13015 Marseille, France
| | - Najet Srairi-Abid
- Institut Pasteur de Tunis, Laboratoire des Venins et biomolécules thérapeutiques LR11IPT08, Tunis 1002, Tunisia.
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Abstract
Turkey pancreatic phospholipase (TPP) has been purified from delipidated pancreases. The purification included ammonium sulfate fractionation, acidic (pH 5) treatment, followed by sequencial column chromatographies on DEAE-cellulose, Sephadex G-75, and reverse phase high pressure liquid chromatography. The purified enzyme was found to be a monomeric protein with molecular mass of 14 kDa. The optimal activity was measured at pH 8 and 37 degrees C using egg yolk emulsion as substrate. Our results show that the enzyme (TPP) was not stable for 1 h at 60 degrees C, and that bile salt and Ca2+ were required for the expression of the purified enzyme. The sequence of the N-terminal amino acids of the purified enzyme shows a very close similarity between TPP and all other known pancreatic phospholipases.
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Affiliation(s)
- Riadh Ben Salah
- Laboratory of Biochemistry, ENIS Soukra Road, 3038 Sfax, Tunisia
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Elleuch A, Chaâbene Z, Grubb DC, Drira N, Mejdoub H, Khemakhem B. Morphological and biochemical behavior of fenugreek (Trigonella foenum-graecum) under copper stress. Ecotoxicol Environ Saf 2013; 98:46-53. [PMID: 24135423 DOI: 10.1016/j.ecoenv.2013.09.028] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 09/19/2013] [Accepted: 09/20/2013] [Indexed: 06/02/2023]
Abstract
The effects of copper on germination and growth of fenugreek (Trigonella foenum-graecum) was investigated separately using different concentrations of CuSO₄. The germination percentage and radical length had different responses to cupric ions: the root growth increased with increasing copper concentration up to 1 mM Cu²⁺ and was inhibited thereafter. In contrast, the germination percentage was largely unaffected by concentrations of copper below 10 mM. The reduction in root growth may have been due to inhibition of hydrolytic enzymes such as amylase. Indeed, the average total amylolytic activity decreased from the first day of treatment with [Cu²⁺] greater than 1 mM. Furthermore, copper affected various plant growth parameters. Copper accumulation was markedly higher in roots as compared to shoots. While both showed a gradual decrease in growth, this was more pronounced in roots than in leaves and in stems. Excess copper induced an increase in the rate of hydrogen peroxide (H₂O₂) production and lipid peroxidation in all plant parts, indicating oxidative stress. This redox stress affected leaf chlorophyll and carotenoid content which decreased in response to augmented Cu levels. Additionally, the activities of proteins involved in reactive oxygen species (ROS) detoxification were affected. Cu stress elevated the ascorbate peroxidase (APX) activity more than two times at 10 mM CuSO₄. In contrast, superoxide dismutase (SOD) and catalase (CAT) levels showed only minor variations, only at 1 mM Cu²⁺. Likewise, total phenol and flavonoid contents were strongly induced by low concentrations of copper, consistent with the role of these potent antioxidants in scavenging ROS such as H₂O₂, but returned to control levels or below at high [Cu²⁺]. Taken together, these results indicate a fundamental shift in the plant response to copper toxicity at low versus high concentrations.
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Affiliation(s)
- Amine Elleuch
- Laboratoire des Biotechnologies Végétales Appliquées à l'Amélioration des Cultures, Faculté des Science de Sfax, Université de Sfax BP 1171, Sfax 3000, Tunisia.
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Ben Bacha A, Abid I, Horchani H, Mejdoub H. Enzymatic properties of stingray Dasyatis pastinaca group V, IIA and IB phospholipases A(2): a comparative study. Int J Biol Macromol 2013; 62:537-42. [PMID: 24120965 DOI: 10.1016/j.ijbiomac.2013.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 10/01/2013] [Accepted: 10/04/2013] [Indexed: 11/18/2022]
Abstract
In the present study, we have purified the group V phospholipase from the heart of cartilaginous fish stingray Dasyatis pastinaca and compared its biochemical properties with group IIA (sPLA2-IIA) and IB (sPLA2-IB) phospholipases previously purified from pancreas and intestine, respectively. Group V phospholipase (sPLA2-V) was purified to homogeneity by heat treatment, ammonium sulphate precipitation and RP-HPLC. The N-terminal sequence of the purified sPLA2-V exhibits a high degree of homology with those of mammal. The enzyme was found to be monomeric with a molecular mass estimation of 14 kDa. The specific activity of the purified enzyme, measured at pH 8 and 37 °C was 52 U/mg. Like sPLA2-IB and sPLA2-IIA, the sPLA2-V is found to be stable between pH 3 and 11 after 30 min of incubation. The purified sPLA2-V retained 65% of its activity after 10 min of incubation at 70 °C and it absolutely requires Ca(2+) for enzymatic activity. In addition it displayed high tolerance to organic solvents. Kinetic parameters Kmapp, kcat and the deduced catalytic efficiency (kcat/Kmapp) of the purified group-V, -IB and -IIA PLA2s were determined using phosphatidylethanolamine (PE), phosphatidylcholine (PC) or phosphatidylserine (PS) as substrate. The three enzymes hydrolyze the zwiterionic PE and PC substrates more efficiently than anionic PS substrate.
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Affiliation(s)
- Abir Ben Bacha
- Biochemistry Department, Science College, King Saud University, P.O. Box 22452, Riyadh 11495, Saudi Arabia; Laboratory of Plant Biotechnology Applied to Crop Improvement, Faculty of Science of Sfax, University of Sfax, Sfax 3038, Tunisia.
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Dahech I, Fakhfakh J, Damak M, Belghith H, Mejdoub H, Belghith KS. Structural determination and NMR characterization of a bacterial exopolysaccharide. Int J Biol Macromol 2013; 59:417-22. [DOI: 10.1016/j.ijbiomac.2013.04.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 03/30/2013] [Accepted: 04/12/2013] [Indexed: 10/26/2022]
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Ben Bacha A, Daihan SK, Moubayed NMS, Mejdoub H. Purification and characterization of a phospholipase A2-IIA from common stingray (Dasyatis pastinaca) intestine. Indian J Biochem Biophys 2013; 50:186-195. [PMID: 23898481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A phospholipase A2 belonging to IIA group secretory PLA2 was isolated and purified to homogeneity from the intestine of common stingray (Dasyatis pastinaca) using acidic treatment (pH 1.5) and ammonium sulphate precipitation methods combined with single-column ion-exchange chromatography. The purified enzyme was found to be a glycosylated monomeric protein with a molecular mass of about 14 kDa. The stingray sPLA2-IIA had optimum activity at 45 degrees C, unlike known mammalian PLA2-IIAs, which show optimum activity at 37 degrees C. The purified enzyme exhibited a specific activity of 290 U/mg at optimal conditions (pH 9.5 and 45 degrees C) in the presence of 6 mM NaDC and 8 mM CaCl2 with egg yolk as substrate. The NH2-terminal sequence of the enzyme and some protein fragments obtained from its tryptic digestion were also determined. All sequences obtained were similar to those of sPLA2-IIA. The enzyme also showed good stability in the presence of organic solvents, acidic and alkaline pH media and high temperature conditions. Thus, the purified enzyme exhibited a number of unique and promising properties, making it a potential possible candidate for future applications in the treatment of phospholipid-rich industrial effluents and synthesis of useful preparations for the food production and processing industry.
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Affiliation(s)
- Abir Ben Bacha
- Biochemistry Department, Science College, King Saud University, PO Box 22452, Riyadh 11495, Saudi Arabia.
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Ben Bacha A, Al-Daihan SK, Mejdoub H. Purification, characterization and bactericidal activities of phospholipase A2 from the dromedary intestine. Int J Biol Macromol 2013; 57:156-64. [DOI: 10.1016/j.ijbiomac.2013.03.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 03/04/2013] [Accepted: 03/06/2013] [Indexed: 11/28/2022]
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Dahech I, Harrabi B, Hamden K, Feki A, Mejdoub H, Belghith H, Belghith KS. Antioxidant effect of nondigestible levan and its impact on cardiovascular disease and atherosclerosis. Int J Biol Macromol 2013; 58:281-6. [PMID: 23624165 DOI: 10.1016/j.ijbiomac.2013.04.058] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 04/14/2013] [Accepted: 04/17/2013] [Indexed: 11/16/2022]
Abstract
Levan polysaccharide, a type of fructan, has been shown to favorably affect diabetes type 2 and hypercholesterolemia. Recent reports have indicated that excessive oxidative stress contributes to the development of atherosclerosis linked metabolic syndrome. The objective of this current study was to investigate the possible protection against oxidative stress linked atherosclerosis. A group of twenty four male rats was divided into four subgroups; a normal diet group (Control), normal rats received levan (L), a high-cholesterol diet group (Chol) and a high-cholesterol diet with 5% (w/w) levan group. After the treatment period, the plasma antioxidant enzymes and lipid profiles were determined. Our results show that treatment with levan positively changed plasma antioxidant enzyme activities by increasing superoxide dismutase (SOD) and catalase (CAT) by 40% and 28%, respectively, in heart. Similarly, the treatment of Chol fed groups with levan positively changed lipid profiles by decreasing total cholesterol, triglycerides and LDL-cholesterol by 50%, 38.33% and 64%, respectively. Thus may have potential antioxidant effects and could protect against oxidative stress linked atherosclerosis.
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Affiliation(s)
- Imen Dahech
- Biochemistry Laboratory, Faculty of Sciences of Sfax, Sfax, Tunisia.
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17
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Nasri R, Hassen Zrour S, Rebai H, Fadhel Najjar M, Neffeti F, Bergaoui N, Mejdoub H, Tabka Z. Grip strength is a predictor of bone mineral density among adolescent combat sport athletes. J Clin Densitom 2013; 16:92-7. [PMID: 22980488 DOI: 10.1016/j.jocd.2012.07.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Revised: 07/23/2012] [Accepted: 07/25/2012] [Indexed: 11/24/2022]
Abstract
The aim of this study was firstly to investigate the correlation between bone parameters and grip strength (GS) in hands, explosive legs power (ELP), and hormonal parameters; second, to identify the most determinant variables of bone mineral density (BMD) among adolescent combat sport athletes. Fifty combat sport athletes aged 17.1 ± 0.2 year were compared with 30 sedentary subjects matched for age, height, and pubertal stage. For all subjects, the BMD in deferent sites associated with anthropometric parameters were measured by dual-energy X-ray absorptiometry. The growth hormone (GH) and testosterone (TESTO) concentrations were tested. The GS in dominant (GSDA) and nondominant arms (GSNDA) and ELP were evaluated. All BMD measured were greater in athletes than in sedentary group (p<0.01). The GS and ELP showed higher values in athletes than in sedentary group (p<0.01). The BMD in all sites were correlated with weight, but without correlation with height. The GSNDA and ELP were significantly correlated with BMD of both spine and legs. The GH was correlated with the BMD of whole body and spine (p<0.05). The TESTO was only correlated with BMD of the arms (p<0.01). The best predictor of BMD measurements is GSNDA. This study has proved the osteogenic effect of combat sports practice, especially judo and karate kyokushinkai. Therefore, children and adolescent should be encouraged to participate in combat sport. Moreover, it suggested that the best model predicting BMD in different sites among adolescent combat sports athletes was the GSNDA.
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Affiliation(s)
- Raouf Nasri
- Laboratory of Physiology and Functional Explorations, Faculty of Medicine, Sousse, Tunisia.
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Zarai Z, Balti R, Mejdoub H, Gargouri Y, Sayari A. Process for extracting gelatin from marine snail (Hexaplex trunculus): Chemical composition and functional properties. Process Biochem 2012. [DOI: 10.1016/j.procbio.2012.06.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Dahech I, Belghith KS, Belghith H, Mejdoub H. Partial purification of a Bacillus licheniformis levansucrase producing levan with antitumor activity. Int J Biol Macromol 2012; 51:329-35. [DOI: 10.1016/j.ijbiomac.2012.04.030] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 04/17/2012] [Accepted: 04/30/2012] [Indexed: 11/25/2022]
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Abstract
We purified to homogeneity and characterized a heat stable thioredoxin which catalyzes thiol/disulfide exchange reaction, for the first time from dromedary pancreas. The purification involved heat and acidic treatment (90 °C; pH 2.5), precipitation by ammonium sulphate and ethanol, respectively followed by sequential column chromatography reverse HPLC column, and it resulted in an apparently pure protein after a 217-fold purification with a final yield of 55% of the initial thioredoxin activity. The thioredoxin preparation obtained was homogeneous as judged by polyacrylamide gel electrophoresis and the presence of valine as the only NHt-terminal amino acid. MALDI-TOF mass spectrometry revealed that the protein has a molecular mass of 11,302.9 Da. The first 40 amino-acid residues at the N-terminal extremity of purified DrTrx was determined by automatic Edman degradation and showed a high sequence homology with known Thioredoxin. It contained he tetrapeptide-Cys-Gly-Pro-Cys-, which constitutes the active site of mammalian thioredoxins. DrTrx activity was compatible with the presence of organic solvents and the maximum activity appeared at pH 7.5 using the insulin precipitation assay. Thioredoxin stability in the presence of organic solvents, as well as in acidic and alkaline pHs and at high temperatures makes it a good candidate for its application in pharmaceutical and food industry.
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Affiliation(s)
- Abir G Ben Bacha
- Biochemistry Department, Science College, King Saud University, P.O. box 22452, Riyadh, 11495, Saudi Arabia.
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Zarai Z, Boulais N, Marcorelles P, Gobin E, Bezzine S, Mejdoub H, Gargouri Y. Immunohistochemical localization of hepatopancreatic phospholipase in gastropods mollusc, Littorina littorea and Buccinum undatum digestive cells. Lipids Health Dis 2011; 10:219. [PMID: 22114916 PMCID: PMC3254598 DOI: 10.1186/1476-511x-10-219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 11/25/2011] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Among the digestive enzymes, phospholipase A2 (PLA2) hydrolyzes the essential dietary phospholipids in marine fish and shellfish. However, we know little about the organs that produce PLA2, and the ontogeny of the PLA2-cells. Accordingly, accurate localization of PLA2 in marine snails might afford a better understanding permitting the control of the quality and composition of diets and the mode of digestion of lipid food. RESULTS We have previously producted an antiserum reacting specifically with mSDPLA2. It labeled zymogen granules of the hepatopancreatic acinar cells and the secretory materials of certain epithelial cells in the depths of epithelial crypts in the hepatopancreas of snail. To confirm this localization a laser capture microdissection was performed targeting stained cells of hepatopancreas tissue sections. A Western blot analysis revealed a strong signal at the expected size (30 kDa), probably corresponding to the PLA2. CONCLUSIONS The present results support the presence of two hepatopancreatic intracellular and extracellular PLA2 in the prosobranchs gastropods molluscs, Littorina littorea and Buccinum undatum and bring insights on their localizations.
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Affiliation(s)
- Zied Zarai
- Laboratoire de biochimie et de génie enzymatique des lipases, ENIS BPW 1173 Université de Sfax-Tunisia
| | - Nicholas Boulais
- Laboratoire de Neurobiologie Cutanée, CHU Morvan, Université de Brest, 29609 BREST cedex France
| | - Pascale Marcorelles
- Service d'Anatomie Pathologique, Pôle de Biologie-Pathologie, CHU Morvan, Université de Brest, 29609 BREST cedex France
| | - Eric Gobin
- Service d'Anatomie Pathologique, Pôle de Biologie-Pathologie, CHU Morvan, Université de Brest, 29609 BREST cedex France
| | - Sofiane Bezzine
- Laboratoire de biochimie et de génie enzymatique des lipases, ENIS BPW 1173 Université de Sfax-Tunisia
| | - Hafedh Mejdoub
- Laboratoire de biochimie et de génie enzymatique des lipases, ENIS BPW 1173 Université de Sfax-Tunisia
| | - Youssef Gargouri
- Laboratoire de biochimie et de génie enzymatique des lipases, ENIS BPW 1173 Université de Sfax-Tunisia
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Dahech I, Belghith KS, Hamden K, Feki A, Belghith H, Mejdoub H. Antidiabetic activity of levan polysaccharide in alloxan-induced diabetic rats. Int J Biol Macromol 2011; 49:742-6. [DOI: 10.1016/j.ijbiomac.2011.07.007] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 07/04/2011] [Accepted: 07/07/2011] [Indexed: 12/12/2022]
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Zarai Z, Kadri A, Ben Chobba I, Ben Mansour R, Bekir A, Mejdoub H, Gharsallah N. The in-vitro evaluation of antibacterial, antifungal and cytotoxic properties of Marrubium vulgare L. essential oil grown in Tunisia. Lipids Health Dis 2011; 10:161. [PMID: 21936887 PMCID: PMC3196909 DOI: 10.1186/1476-511x-10-161] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 09/21/2011] [Indexed: 11/11/2022] Open
Abstract
Background In order to validate its antiseptic and anticancer properties with respect to traditional uses, we have screened for the first time the antimicrobial activity of aerial parts of M. vulgare L. essential oil against different pathogenic microorganisms and the cytotoxic activity against HeLa cell lines. Methods The agar disk diffusion method was used to study the antibacterial activity of M. vulgare essential oil against 12 bacterial and 4 fungi strains. The disc diameters of zone of inhibition (DD), the minimum inhibitory concentrations (MIC) and the concentration inhibiting 50% (IC50) were investigated to characterize the antimicrobial activities of this essential oil. The in vitro cytotoxicity of M. vulgare essential oil was examined using a modified MTT assay; the viability and the IC50 were used to evaluate this test. Results The antimicrobial activity of the essential oil was investigated in order to evaluate its efficacy against the different tested microorganisms. The present results results showed a significant activity against microorganisms especially Gram (+) bacteria with inhibition zones and minimal inhibitory concentration values in the range of 6.6-25.2 mm and 1120-2600 μg/ml, respectively, whereas Gram (-) bacteria exhibited a higher resistance. As far as the antifungal activity, among four strains tested, Botrytis cinerea exhibited the strongest activity with inhibition zones of 12.6 mm. However, Fusarium solani, Penicillium digitatum and Aspergillus niger were less sensitive to M. vulgare essential oil. About the citotoxicity assay, this finding indicate the capability of this essential oil to inhibited the proliferation of HeLa cell lines under some conditions with IC50 value of 0.258 μg/ml. Conclusion This investigation showed that the M. vulgare essential oil has a potent antimicrobial activity against some Gram (+) pathogenic bacteria and Botrytis cinerea fungi. The present studies confirm the use of this essential oil as anticancer agent. Further research is required to evaluate the practical values of therapeutic applications.
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Affiliation(s)
- Zied Zarai
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS, BPW, 1173 Sfax, University of Sfax, Tunisia
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Dahech I, Belghith KS, Hamden K, Feki A, Belghith H, Mejdoub H. Oral administration of levan polysaccharide reduces the alloxan-induced oxidative stress in rats. Int J Biol Macromol 2011; 49:942-7. [PMID: 21925206 DOI: 10.1016/j.ijbiomac.2011.08.011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2011] [Revised: 07/29/2011] [Accepted: 08/11/2011] [Indexed: 11/29/2022]
Abstract
This study aimed to evaluate the effect of a polysaccharide named levan, which was produced by new isolated bacteria, on oxidative stress and hyperglycemia in alloxan-induced diabetic rats. Levan polysaccharide was given in drinking water for 60 days at a daily dose equivalent to 2%. The oral administration of levan in diabetic rats caused a decrease in glucose level in plasma and an increase of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) activities in both pancreas and liver. Furthermore, a protective action against hepatic and pancreatic toxicity in diabetic rats was clearly observed. Furthermore, a significant decrease in hepatic and pancreatic indices toxicity was observed, i.e., alkalines phosphatases (ALP), aspartate and lactate transaminases (AST and ALT), lactate deshydrogenases (LDH) activities and the thiobarbituric acid-reactive substances (TBARs). These beneficial effects of levan were confirmed by histological findings in hepatic and pancreatic tissues of diabetic rats. This study demonstrates for the first time that levan is efficient in inhibiting hyperglycemia and oxidative stress induced by diabetes and suggests that administration of levan may be helpful in the prevention of diabetic complications associated with oxidative stress.
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Affiliation(s)
- Imen Dahech
- Biochemistry Laboratory, Faculty of Sciences of Sfax, PB 802, 3018 Sfax, Tunisia.
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Bacha AGB, Mejdoub H. Proteolytic cleavage of stingray phospholipase A2: isolation and biochemical characterization of an active N-terminal form. Lipids Health Dis 2011; 10:124. [PMID: 21791082 PMCID: PMC3180402 DOI: 10.1186/1476-511x-10-124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Accepted: 07/26/2011] [Indexed: 11/23/2022] Open
Abstract
Background Mammalian GIB-PLA2 are well characterized. In contrast, much less is known about aquatic ones. The aquatic world contains a wide variety of living species and, hence represents a great potential for discovering new lipolytic enzymes. The aim of this study was to check some biochemical and structural properties of a marine stingray phospholipase A2 (SPLA2). Results The effect of some proteolytic enzymes on SPLA2 was checked. Chymotrypsin and trypsin were able to hydrolyze SPLA2 in different ways. In both cases, only N-terminal fragments were accumulated during the hydrolysis, whereas no C-terminal fragment was obtained in either case. Tryptic and chymotryptic attack generated 13 kDa and 12 kDa forms of SPLA2, respectively. Interestingly, the SPLA2 13 kDa form was inactive, whereas the SPLA2 12 kDa form conserved almost its full phospholipase activity. In the absence of bile slats both native and 12kDa SPLA2 failed to catalyse the hydrolysis of PC emulsion. When bile salts were pre-incubated with the substrate, the native kinetic protein remained linear for more than 25 min, whereas the 12 kDa form activity was found to decrease rapidly. Furthermore, The SPLA2 activity was dependent on Ca2+; other cations (Mg2+, Mn2+, Cd2+ and Zn2+) reduced the enzymatic activity notably, suggesting that the arrangement of the catalytic site presents an exclusive structure for Ca2+. Conclusions Although marine and mammal pancreatic PLA2 share a high amino acid sequence homology, polyclonal antibodies directed against SPLA2 failed to recognize mammal PLA2 like the dromedary pancreatic one. Further investigations are needed to identify key residues involved in substrate recognition responsible for biochemical differences between the 2 classes of phospholipases.
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Affiliation(s)
- Abir G Ben Bacha
- Biochemistry Department, Science College, King Saud University, PO Box 22452, 11495 Riyadh, Saudi Arabia.
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Zarai Z, Boulais N, Karray A, Misery L, Bezzine S, Rebai T, Gargouri Y, Mejdoub H. Immunohistochemical localization of hepatopancreatic phospholipase A2 in Hexaplex trunculus digestive cells. Lipids Health Dis 2011; 10:91. [PMID: 21631952 PMCID: PMC3127788 DOI: 10.1186/1476-511x-10-91] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 06/01/2011] [Indexed: 11/16/2022] Open
Abstract
Background Mammalian sPLA2-IB localization cell are well characterized. In contrast, much less is known about aquatic primitive ones. The aquatic world contains a wide variety of living species and, hence represents a great potential for discovering new lipolytic enzymes and the mode of digestion of lipid food. Results The marine snail digestive phospholipase A2 (mSDPLA2) has been previously purified from snail hepatopancreas. The specific polyclonal antibodies were prepared and used for immunohistochimical and immunofluorescence analysis in order to determine the cellular location of mSDPLA2. Our results showed essentially that mSDPLA2 was detected inside in specific vesicles tentatively named (mSDPLA2+) granules of the digestive cells. No immunolabelling was observed in secretory zymogene-like cells. This immunocytolocalization indicates that lipid digestion in the snail might occur in specific granules inside the digestive cells. Conclusion The cellular location of mSDPLA2 suggests that intracellular phospholipids digestion, like other food components digestion of snail diet, occurs in these digestive cells. The hepatopancreas of H. trunculus has been pointed out as the main region for digestion, absorption and storage of lipids.
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Affiliation(s)
- Zied Zarai
- Laboratoire de biochimie et de génie enzymatique des lipases, ENIS BPW 1173 Université de Sfax-Tunisia
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Zarai Z, Frikha F, Balti R, Miled N, Gargouri Y, Mejdoub H. Nutrient composition of the marine snail (Hexaplex trunculus) from the Tunisian Mediterranean coasts. J Sci Food Agric 2011; 91:1265-1270. [PMID: 21328367 DOI: 10.1002/jsfa.4309] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2010] [Revised: 11/21/2010] [Accepted: 01/03/2011] [Indexed: 05/30/2023]
Abstract
BACKGROUND Marine snail (Hexaplex trunculus) presents increasing nutritional, commercial and economical importance, being widely consumed in northern Africa, particularly in Mediterranean countries. From a nutritional point of view there is still limited information on the chemical composition of edible tissues (meat and hepatopancreas) of this species. Therefore, the aims of the present work were to study the proximate chemical composition, fatty acid and amino acid profiles of H. trunculus from the Tunisian Mediterranean coasts. RESULTS Fatty acid profiles showed that the polyunsaturated fatty acids (PUFA) content is higher than the saturated fatty acids (SFA). The yields of PUFA and SFA present in the meat fat were 68.2% and 33.4% of the total fatty acids, respectively. Similar values were obtained in the hepatopancreatic lipidic fraction. Snail tissues contain valuable concentrations of PUFA, especially n-6 and n-3 with chain lengths of 20 and 22 carbons. All edible tissues were valuable sources of essential amino acids. Aspartic acid is the major amino acids present in the meat and hepatopancreas. The concentrations of nutrients were also determined in the hepatopancreas and meat of H. trunculus. Significantly high concentrations of minerals and trace elements were found in these tissues. CONCLUSION This study suggests that H. trunculus is an important source of protein and essential amino acids. Furthermore, the snail lipidic fraction contains high proportions of polyunsaturated fatty acids benefical for human health.
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Affiliation(s)
- Zied Zarai
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases-Ecole Nationale d'Ingénieurs de Sfax, B.P 1173, 3038 Sfax, Tunisia.
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Rjeibi I, Mabrouk K, Mosrati H, Berenguer C, Mejdoub H, Villard C, Laffitte D, Bertin D, Ouafik L, Luis J, Elayeb M, Srairi-Abid N. Purification, synthesis and characterization of AaCtx, the first chlorotoxin-like peptide from Androctonus australis scorpion venom. Peptides 2011; 32:656-63. [PMID: 21262299 DOI: 10.1016/j.peptides.2011.01.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 01/11/2011] [Accepted: 01/11/2011] [Indexed: 01/18/2023]
Abstract
AaCtx is the first chlorotoxin-like peptide isolated from Androctonus australis scorpion venom. Its amino acid sequence shares 70% similarity with chlorotoxin from Leiurus quinquestriatus scorpion venom, from which it differs by twelve amino acids. Due to its very low concentration in venom (0.05%), AaCtx was chemically synthesized. Both native and synthetic AaCtx were active on invasion and migration of human glioma cells. However, their activity was found to be lower than that of chlorotoxin. The molecular model of AaCtx shows that most of amino acids differing between AaCtx and chlorotoxin are localized on the N-terminal loop and the α-helix. Based on known compounds that block chloride channels, we suggest that the absence of negative charged amino acids on AaCtx structure may be responsible for its weak activity on glioma cells migration and invasion. This finding serves as a starting point for structure-function relationship studies leading to design high specific anti-glioma drugs.
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Affiliation(s)
- Ilhem Rjeibi
- Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, 13, Place Pasteur, BP 74, 1002 Belvédère, Universités Tunis-El Manar, Tunisia
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Frikha F, Miled N, Bacha A, Mejdoub H, Gargouri Y. Structural Homologies, Importance for Catalysis and Lipid Binding of the N-Terminal Peptide of a Fungal and a Pancreatic Lipase. Protein Pept Lett 2010; 17:254-9. [DOI: 10.2174/092986610790226049] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Zarai Z, Bacha AB, Horchani H, Bezzine S, Zouari N, Gargouri Y, Mejdoub H. A novel hepatopancreatic phospholipase A2 from Hexaplex trunculus with digestive and toxic activities. Arch Biochem Biophys 2010; 494:121-9. [DOI: 10.1016/j.abb.2009.11.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2009] [Accepted: 11/15/2009] [Indexed: 11/16/2022]
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Ben Salah R, Gargouri A, Verger R, Gargouri Y, Mejdoub H. Expression in Pichia pastoris X33 of His-tagged lipase from a novel strain of Rhizopus oryzae and its mutant Asn 134 His: purification and characterization. World J Microbiol Biotechnol 2009. [DOI: 10.1007/s11274-009-0024-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Srairi-Abid N, Shahbazzadeh D, Chatti I, Mlayah-Bellalouna S, Mejdoub H, Borchani L, Benkhalifa R, Akbari A, El Ayeb M. Hemitoxin, the first potassium channel toxin from the venom of the Iranian scorpion Hemiscorpius lepturus. FEBS J 2008; 275:4641-50. [DOI: 10.1111/j.1742-4658.2008.06607.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
OBJECTIVES The aim of this study was to check some biochemical and structural properties of ostrich and turkey pancreatic lipases (OPL and TPL, respectively). METHODS Limited proteolysis of OPL and TPL was performed in conditions similar to those reported for porcine pancreatic lipase. RESULTS In the absence of bile salts and colipase, OPL failed to catalyze the hydrolysis of pure tributyrin or efficiently hydrolyze olive oil emulsion. When bile salts and colipase were preincubated with the substrate, the OPL kinetic behavior remained linear for more than 30 minutes. The enzyme presented a penetration power value into an egg phosphatidylcholine monomolecular film that was comparable to that of HPL and lower than that of TPL. Chymotrypsin, trypsin, and thermolysin were able to hydrolyze OPL and TPL in different ways. In both cases, only N-terminal fragments accumulated during the hydrolysis, whereas no C-terminal fragment was obtained in either case. Tryptic cleavage of OPL and TPL completely degraded the enzymes. Nevertheless, chymotryptic attack generated 35-kd and 43-kd forms for TPL and OPL, respectively. Interestingly, the OPL 43-kd form was inactive, whereas the TPL 35-kd protein conserved its lipolytic activity. CONCLUSIONS OPL, TPL, and mammal pancreatic lipases share a high amino acid sequence homology. Further investigations are, however, needed to identify key residues involved in substrate recognition responsible for biochemical differences between the 2 classes of lipases.
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Affiliation(s)
- Abir Ben Bacha
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, Ecole Nationale d'Ingénieurs de Sfax, Tunisia
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Ben Bacha A, Gargouri Y, Bezzine S, Mosbah H, Mejdoub H. Ostrich pancreatic phospholipase A2: Purification and biochemical characterization. J Chromatogr B Analyt Technol Biomed Life Sci 2007; 857:108-14. [PMID: 17656163 DOI: 10.1016/j.jchromb.2007.07.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2007] [Revised: 06/29/2007] [Accepted: 07/03/2007] [Indexed: 11/19/2022]
Abstract
Ostrich pancreatic phospholipase A(2) (OPLA(2)) was purified from delipidated pancreases. Pure protein was obtained after heat treatment (70 degrees C), precipitation by ammonium sulphate and ethanol, respectively followed by sequential column chromatography on MonoQ Sepharose and size exclusion HPLC column. Purified OPLA(2), which is not a glycosylated protein, was found to be monomeric protein with a molecular mass of 13773.93 Da. A specific activity of 840U/mg for purified OPLA(2) was measured at optimal conditions (pH 8.2 and 37 degrees C) in the presence of 4 mM NaTDC and 10 mM CaCl(2) using PC as substrate. This enzyme was also found to be able to hydrolyze, at low surface pressure, 1,2-dilauroyl-sn-glycero-3 phosphocholine (di C(12)-PC) monolayers. Maximal activity was measured at 5-8 mNm(-1). The sequence of the first 22 amino-acid residues at the N-terminal extremity of purified bird PLA(2) was determined by automatic Edman degradation and showed a high sequence homology with known mammal pancreatic secreted phospholipases A(2).
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Affiliation(s)
- Abir Ben Bacha
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS route de Soukra, 3038, Sfax, Tunisia
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Cherif S, Fendri A, Miled N, Trabelsi H, Mejdoub H, Gargouri Y. Crab digestive lipase acting at high temperature: Purification and biochemical characterization. Biochimie 2007; 89:1012-8. [PMID: 17395356 DOI: 10.1016/j.biochi.2007.02.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2006] [Accepted: 02/06/2007] [Indexed: 11/18/2022]
Abstract
In recent years, recovery and characterization of enzymes from fish and aquatic invertebrates have taken place and this had led to the emergence of some interesting new applications of these enzymes. However, much less is known about lipases from crustaceans. A lipolytic activity was located in the crab digestive glands (hepatopancreas), from which a crab digestive lipase (CDL) was purified. Pure CDL has a molecular mass of 65kDa as determined by SDS/PAGE analysis. Unlike known digestive lipases, CDL displayed its maximal activity on long and short-chain triacylglycerols at a temperature of 60 degrees C. A specific activity of 500U/mg or 130U/mg was obtained with TC(4) or olive oil as substrate, respectively. Only 10% of the maximal activity was detected at 37 degrees C. The enzyme retained 80% of its maximal activity when incubated during 10 min at 60 degrees C, and was completely inactivated at a temperature higher than 65 degrees C. Interestingly, neither colipase, nor bile salts were detected in the crab hepatopancreas. Which suggests that colipase evolved in invertebrates simultaneously with the appearance of an exocrine pancreas and a true liver which produce bile salts. No similarity between the 13 N-terminal amino acid residues of CDL was found with those of known other digestive lipases.
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Affiliation(s)
- Slim Cherif
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS, BPW 3038, Sfax, Tunisia
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Ben Salah R, Ghamghui H, Miled N, Mejdoub H, Gargouri Y. Production of butyl acetate ester by lipase from novel strain of Rhizopus oryzae. J Biosci Bioeng 2007; 103:368-72. [PMID: 17502279 DOI: 10.1263/jbb.103.368] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Accepted: 01/20/2007] [Indexed: 11/17/2022]
Abstract
A new lipase preparation from Rhizopus oryzae was used to catalyze the esterification reaction between acetic acid and butanol to produce butyl acetate ester (pineapple flavor). This flavor compound can be used in food, cosmetic and pharmaceutical industries. Only 3% of butyl acetate was obtained when free lipase was used in the synthesis containing only the substrates. In contrast, the conversion yield reached 25% when immobilized lipase was used under the same conditions. The synthesis of butyl acetate catalyzed by immobilized lipase in nonconventional media was optimized. A maximum conversion yield of 60% in a solvent-free system was obtained under the following conditions: amount of immobilized lipase, 500 IU; amount of initially added water, 45%; acetic acid/butanol molar ratio, 1:1; and in incubation temperature, 37 degrees C. Immobilized lipase could be repeatedly used for three cycles without a decrease in synthesis activity. The production of butyl acetate esters by immobilized R. oryzae lipase was also studied in the presence of organic solvents. Compared with a solvent-free system, the synthesis activity was improved in the presence of heptane and hexane with conversion yields of 80% and 76%, respectively. However, solvent-free systems tend to purify more easily the products without any toxicity and inflammability problems.
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Affiliation(s)
- Riadh Ben Salah
- Laboratoire de Biochimie et de Génie enzymatique des lipases, Ecole Nationale des Ingénieurs de Sfax, Route de Soukra, Boite Postale W, 3038 Sfax, Tunisia
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Ben Bacha A, Frikha F, Djemal I, Fendri A, Miled N, Gargouri Y, Mejdoub H. Biochemical and structural comparative study between bird and mammal pancreatic colipases. J Lipid Res 2006; 47:2701-11. [PMID: 16957180 DOI: 10.1194/jlr.m600242-jlr200] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Three colipases were purified from pancreas of two birds (ostrich and turkey) and one mammal (dromedary). After acidic and/or heat treatment and precipitation by sulfate ammonium and then ethanol, cofactors were purified by Sephadex G-50 gel filtration followed by ion-exchange chromatography first on Mono S and then on Mono Q. One molecular form was obtained from each species with a molecular mass of approximately 10 kDa. Cofactors were not glycosylated. The N-terminal sequences of the three purified cofactors showed high sequence homology. A 90 amino acid sequence of the ostrich cofactor was established based on peptide sequences from four different digests of the denaturated protein using trypsin, chymotrypsin, thermolysin, or staphylococcal protease. This sequence exhibited a high degree of homology with chicken and mammal cofactors. Bile salt-inhibited pancreatic lipases from five species were activated to variable extents by colipases from bird and mammal origins. The bird pancreatic lipase-colipase system appears to be functionally similar to homologous lipolytic systems from higher mammals. Our comparative study showed that mammal colipase presents a lower activation level toward bird lipases than the bird counterpart. Three-dimensional modeling of ostrich colipase suggested a structural explanation of this fact.
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Affiliation(s)
- Abir Ben Bacha
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, 3038 Sfax, Tunisia
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Cherif S, Miled N, Kammoun M, Mejdoub H, Gargouri Y. Purification and biochemical characterization of a turkey preduodenal esterase. Comp Biochem Physiol B Biochem Mol Biol 2006; 145:358-64. [PMID: 17046305 DOI: 10.1016/j.cbpb.2006.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Revised: 08/11/2006] [Accepted: 08/26/2006] [Indexed: 11/15/2022]
Abstract
A preduodenal esterase was purified to homogeneity from turkey (Meleagris gallopavo) pharyngial tissue. Pure turkey pregastric esterase (TPrE) was obtained after anion exchange chromatography (DEAE-cellulose), Sephacryl S-200 gel filtration, anion exchange chromatography (Mono-Q sepharose) and affinity chromatography (Blue-Gel Affi Gel). The pure enzyme has an apparent molecular mass of 50 kDa, as determined by SDS/PAGE analysis. The optimum pH and temperature for enzyme activity using tributyrin as substrate were 8.5 and 48 degrees C, respectively. Under these conditions, the specific activity measured was 650 U/mg. No significant lipolytic activity was found when was tested on triolein or liprocil as substrates or with monolayer dicaprin with TPrE. In contrast, TPrE displayed a maximal activities of 800, 680 and 520 U/mg with vinyl acetate, vinyl propionate and vinyl butyrate, respectively. This enzyme retained 75% of its maximal activity when incubated for 30 min at pH 4 and 50 degrees C, but it was completely inactivated after an incubation for 10 min at 60 degrees C. The TPrE N-terminal amino acid sequence showed similarities to the N-terminal sequence of a thioesterase from mallard duck, but no similarity with known preduodenal lipases was found.
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Affiliation(s)
- Slim Cherif
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS route de Soukra, 3038 Sfax-Tunisia
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Salah RB, Mosbah H, Fendri A, Gargouri A, Gargouri Y, Mejdoub H. Biochemical and molecular characterization of a lipase produced by Rhizopus oryzae. FEMS Microbiol Lett 2006; 260:241-8. [PMID: 16842350 DOI: 10.1111/j.1574-6968.2006.00323.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
A novel strain of Rhizopus oryzae WPG secretes a noninduced lipase (ROLw) in the culture medium; purified ROLw is a protein of 29 kDa, the 45 N-terminal amino acid residues were sequenced, this sequence is very homologous to Rhizopus delemar lipase (RDL), Rhizopus niveus lipase (RNL) and R. oryzae lipase (ROL29) sequences; the cloning and sequencing of the part of the gene encoding the mature ROLw, shows two nucleotides differences with RDL, RNL and ROL29 sequences corresponding to the change of the residues 134 and 200; ROLw does not present the interfacial activation phenomenon when using tripropionin or vinyl propionate as substrates; the lipase activity is maximal at pH 8 and at 37 degrees C, specific activities of 3500 or 900 U mg(-1) were measured at 37 degrees C and at pH 8, using olive oil emulsion or tributyrin as substrates, respectively; ROLw is unable to hydrolyse triacylglycerols in the presence of high concentration of bile salts; it is a serine enzyme as it is inhibited by tetrahydrolipstatin and was stable between pH 5 and pH 8.
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Affiliation(s)
- Riadh Ben Salah
- Laboratoire de Biochimie, ENIS, Route de Soukra, BPW, Sfax, Tunisie
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Bacha AB, Gargouri Y, Bezzine S, Mejdoub H. Purification and biochemical characterization of phospholipase A2 from dromedary pancreas. Biochim Biophys Acta Gen Subj 2006; 1760:1202-9. [PMID: 16733083 DOI: 10.1016/j.bbagen.2006.03.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2005] [Revised: 03/09/2006] [Accepted: 03/13/2006] [Indexed: 11/16/2022]
Abstract
Dromedary pancreatic PLA2 (DrPLA2) was purified from delipidated pancreases. Pure protein was obtained after heat and acidic treatment (70 degrees C; pH 3.0), precipitation by ammonium sulphate and ethanol respectively, followed by sequential column chromatographies on Sephadex G-50, MonoS Sepharose, MonoQ Sepharose and C-8 reverse phase high pressure liquid chromatography. Purified DrPLA2, which is not glycosylated protein, was found to be monomeric protein with a molecular mass of 13748.55 Da. A specific activity of 600 U/mg for purified DrPLA2 was measured at optimal conditions (pH 8.0 and 37 degrees C) in the presence of 3 mM NaTDC and 7 mM CaCl(2) using PC as substrate. The sequence of the first fourteen amino-acid residues at the N-terminal extremity of DrPLA2 was determined by automatic Edman degradation. One single sequence was obtained and shows a close similarity with all other known pancreatic secreted phospholipases A2.
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Affiliation(s)
- Abir Ben Bacha
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS route de Soukra, 3038 Sfax, Tunisia
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Fendri A, Frikha F, Mosbah H, Miled N, Zouari N, Bacha AB, Sayari A, Mejdoub H, Gargouri Y. Biochemical characterization, cloning, and molecular modelling of chicken pancreatic lipase. Arch Biochem Biophys 2006; 451:149-59. [PMID: 16780787 DOI: 10.1016/j.abb.2006.04.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2006] [Revised: 04/26/2006] [Accepted: 04/26/2006] [Indexed: 10/24/2022]
Abstract
Chicken pancreatic lipase (CPL) was purified from delipidated pancreas. Pure CPL was obtained after ammonium sulphate fractionation, then DEAE-cellulose, Sephacryl S-200 gel filtration, and FPLC Mono-Q Sepharose columns. The pure lipase is a glycosylated monomer having a molecular mass of about 50kDa. The 23 N-terminal amino acid residues of CPL were sequenced. The sequence is similar to those of avian and mammalian pancreatic lipases. CPL presents the interfacial activation phenomenon tested with tripropionin or vinyl ester. When CPL was inhibited by synthetic detergent (TX-100) or amphipathic protein (BSA), simultaneous addition of bile salts and colipase was required to restore the full CPL activity. In the absence of colipase and bile salts, CPL was unable to hydrolyse tributyrin emulsion. This enzyme can tolerate, more efficiently than HPL, the accumulation of long-chain free fatty acids at the interface when olive oil emulsion was used as substrate in the absence of bile salts and colipase. The CPL activity, under these conditions, was linear whereas that of HPL decreased rapidly. Anti-TPL polyclonal antibodies cross-reacted specifically with CPL. The gene encoding the mature CPL was cloned and sequenced. The deduced amino acid sequence of the mature lipase shows a high degree of homology with the mammalian pancreatic lipases. A 3D structure model of CPL was built using the HPL structure as template. We have concluded that a slight increase in the exposed hydrophobic residues on the surface of CPL, as compared to HPL, could be responsible for a higher tolerance to the presence of long-chain free fatty acids at the lipid/water interface.
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Affiliation(s)
- Ahmed Fendri
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS, BPW, Sfax 3038, Tunisia
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Zouari N, Miled N, Cherif S, Mejdoub H, Gargouri Y. Purification and characterization of a novel lipase from the digestive glands of a primitive animal: The scorpion. Biochim Biophys Acta Gen Subj 2005; 1726:67-74. [PMID: 16154275 DOI: 10.1016/j.bbagen.2005.08.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Revised: 07/29/2005] [Accepted: 08/01/2005] [Indexed: 11/17/2022]
Abstract
Higher animal's lipases are well characterized, however, much less is known about lipases from primitive ones. We choose the scorpion, one of the most ancient invertebrates, as a model of a primitive animal. A lipolytic activity was located in the scorpion digestive glands, from which a scorpion digestive lipase (SDL) was purified. Pure SDL, a glycosylated protein, has a molecular mass of 50 kDa, it presents the interfacial activation phenomenon. It was found to be more active on short-chain triacylglycerols than on long-chain triacylglycerols. SDL is a serine enzyme and possesses one accessible sulfhydryl group which is not essential for the catalysis. Among the NH2-terminal 33 residues, a 17 amino acids sequence shows similarities with sequence of Drosophila melanogaster putative lipase. Interestingly, neither colipase, nor bile salts were detected in the scorpion hepatopancreas. This indicates that colipase evolved in vertebrates simultaneously with the appearance of an exocrine pancreas and a true liver which produces bile salts. Furthermore, polyclonal antibodies directed against SDL failed to recognise the classical digestive lipases. Altogether, these results suggest that SDL is a member of a new group of digestive lipases belonging to invertebrates.
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Affiliation(s)
- Nacim Zouari
- Laboratoire de Biochimie et de Génie Enzymatique des Lipases, ENIS, BPW route de Soukra, 3038 Sfax, Tunisia
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Bacha AB, Gargouri Y, Ali YB, Miled N, Reinbolt J, Mejdoub H. Purification and biochemical characterization of ostrich pancreatic lipase. Enzyme Microb Technol 2005. [DOI: 10.1016/j.enzmictec.2004.07.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Mosbah H, Sayari A, Mejdoub H, Dhouib H, Gargouri Y. Biochemical and molecular characterization of Staphylococcus xylosus lipase. Biochim Biophys Acta Gen Subj 2005; 1723:282-91. [PMID: 15837431 DOI: 10.1016/j.bbagen.2005.03.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Revised: 02/28/2005] [Accepted: 03/01/2005] [Indexed: 11/30/2022]
Abstract
The Staphylococcus xylosus strain secretes a non-induced lipase in culture medium: S. xylosus lipase (SXL). Pure SXL is a monomeric protein (43 kDa). The 23 N-terminal amino acid residues were sequenced. This sequence is identical to that of Staphylococcus simulans lipase (SSL); in addition, it exhibits a high degree of homology with Staphylococcus aureus lipase (SAL NCTC 8530) sequences. The cloning and sequencing of gene part encoding the mature lipase shows one nucleotide difference with SSL, which corresponds to the change of one residue at a position 311. The lipase activity is maximal at pH 8.2 and 45 degrees C. SXL is able to hydrolyse triacylglycerols without chain length specificity. The specific activity of about 1900 U/mg was measured using tributyrin or triolein as substrate at pH 8.2 and at 45 degrees C in the presence of 2 mM CaCl2. In contrast to some previously characterized staphylococcal lipases, Ca2+ is not required to trigger the activity of SXL. SXL was found to be stable between pH 5 and pH 8.5. The enzyme maintains 50% of its activity after a 15-min incubation at 60 degrees C. Using tripropionin or vinyl esters as substrates, SXL does not present the interfacial activation phenomenon. Unlike many lipases, SXL is able to hydrolyse its substrate in the presence of bile salts or amphiphilic proteins. SXL is a serine enzyme, which is inhibited by THL.
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Affiliation(s)
- Habib Mosbah
- Laboratoire de biochimie et de génie enzymatique des lipases, ENIS, BPW 3038 Sfax, Tunisia
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Kamoun F, Mejdoub H, Aouissaoui H, Reinbolt J, Hammami A, Jaoua S. Purification, amino acid sequence and characterization of Bacthuricin F4, a new bacteriocin produced by Bacillus thuringiensis. J Appl Microbiol 2005; 98:881-8. [PMID: 15752334 DOI: 10.1111/j.1365-2672.2004.02513.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS Purification and characterization of a new bacteriocin, Bacthuricin F4 of Bacillus thuringiensis. METHODS AND RESULTS A newly isolated B. thuringiensis subsp. kurstaki strain BUPM4, was shown to produce a novel bacteriocin named Bacthuricin F4. The highest bacteriocin activity was found in the growth medium and evidenced in the late exponential growth phase. Bacthuricin F4 could be purified by a two-step procedure: ammonium sulphate precipitation of protein from culture supernatant followed by a reverse phase chromatography. Upon purification, the specific activity was increased 100-fold. This bacteriocin was heat-stable up to 70 degrees C and resisted up to pH 3.0. Bacthuricin F4 was sensitive to proteases demonstrating its proteinaceous nature. Its molecular mass, determined by mass spectrometry was 3160.05 Da. Direct N-terminal sequencing of Bacthuricin F4 revealed the following sequence: DWTXWSXL. The latter was unique in the databases. Bacthuricin F4 was active against Bacillus species while it had little or no effect on Gram-negative bacteria. CONCLUSIONS A strain BUPM4 of B. thuringiensis subsp. kurstaki, was shown to produce a new bacteriocin named Bacthuricin F4 of both new molecular mass (3160.05 Da) and new amino acid terminal sequence. This is, to our knowledge, the first bacteriocin exhibiting such characteristics reported to be produced by B. thuringiensis. SIGNIFICANCE AND IMPACT OF THE STUDY The bacteriocin produced by the B. thuringiensis strain BUPM4 respond to both criteria of thermostability and stability to low pHs. Thus, it could be used for the control of the related species of Bacillus harmful for agricultural products.
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Affiliation(s)
- F Kamoun
- Laboratoire des Biopesticides, Centre de Biotechnologie de Sfax, Sfax, Tunisia
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Abstract
Turkey pancreatic lipase (TPL) was purified from delipidated pancreases. Pure TPL (glycerol ester hydrolase, EC 3.1.1.3) was obtained after ammonium sulfate fractionation, Sephacryl S-200 gel filtration, anion exchange chromatography (DEAE-Sepharose) and size exclusion column using high performance liquid chromatography system (HPLC). The pure lipase, which is not a glycoprotein, was presented as a monomer having a molecular mass of about 45 kDa. The lipase activity was maximal at pH 8.5 and 37 degrees C. TPL hydrolyses the long chains triacylglycerols more efficiently than the short ones. A specific activity of 4300 U/mg was measured on triolein as substrate at 37 degrees C and at pH 8.5 in the presence of colipase and 4 mM NaTDC. This enzyme presents the interfacial activation when using tripropionin as substrate. TPL was inactivated when the enzyme was incubated at 65 degrees C or at pH less than 5. Natural detergent (NaTDC), synthetic detergent (Tween-20) or amphipatic protein (beta-lactoglobulin A) act as potent inhibitors of TPL activity. To restore the lipase activity inhibited by NaTDC, colipase should be added to the hydrolysis system. When lipase is inhibited by synthetic detergent or protein, simultaneous addition of colipase and NaTDC was required to restore the TPL activity. The first 22 N-terminal amino acid residues were sequenced. This sequence was similar to those of mammal's pancreatic lipases. The biochemical properties of pancreatic lipase isolated from bird are similar to those of mammals.
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Affiliation(s)
- A Sayari
- Laboratoire de lipolyse enzymatique, ENIS, BPW 3038, Sfax, Tunisia
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Abstract
Dromedary pancreatic lipase was purified from delipidated pancreases. Pure dromedary pancreatic lipase (glycerol ester hydrolase, EC 3.1.1.3) was obtained after ammonium sulfate fractionation, Sephadex G-100 gel filtration, anion-exchange (Mono Q Sepharose) and size exclusion column using high performance liquid chromatography (HPLC). The pure lipase is a monomer and has a molecular mass of about 45 kD and a pI of around 4.8. A specific activity of 5900 U/mg was measured on tributyrin as substrate at 37 degrees C in the presence of colipase and 2 mM NaTDC. The first 11 N-terminal amino acid residues and 10 peptides obtained by endoproteinase Glu-C digestion were sequenced. Dromedary pancreatic lipase is very similar to other pancreatic lipases as compared with their N-terminal and some peptides sequences. DrPL is activated by interfaces. The interfacial activation could be related to the presence of a lid and in fact one fragment of this lid domain (P9) was sequenced here: its' role will be discussed below.
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Affiliation(s)
- H Mejdoub
- Laboratoire de Biochimie, ENIS, Sfax, Tunisia
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Abstract
Both thiol groups of native human pancreatic lipase can react with the new hydrophobic sulfhydryl reagent 5-dodecyldithio-2-nitrobenzoic acid (Dod-S-NbS) in the absence of a denaturing agent. Here we describe for the first time the covalent and stoichiometric modification of the inaccessible SHII group of native pancreatic lipase, using a 16-fold molar excess of this hydrophobic sulfhydryl reagent. A direct correlation was found to exist between the covalent modification of this SHII group and the loss of lipase activity. The question has not yet been answered, however, as to how Dod-S-NbS reaches the SHII-containing residue, whereas classical hydrophilic sulfhydryl reagents are unable to do so. This difference in reactivity may be attributable to the hydrophobic character of Dod-S-NbS and its potential capacity to form aggregates inducing a conformational change in the lipase molecule.
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Affiliation(s)
- Y Gargouri
- Laboratoire de Biochimie, Ecole Nationale d'Ingénieurs de Sfax, Tunisia
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Mejdoub H, Le Ret M, Boulanger Y, Maman M, Choay J, Reinbolt J. The complete amino acid sequence of bovine antithrombin (ATIII). J Protein Chem 1991; 10:205-12. [PMID: 1930634 DOI: 10.1007/bf01024785] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Bovine antithrombin (ATIII) is a glycoprotein of Mr 56,600. Its primary structure was established using peptide sequences from five different digests. Bovine ATIII exhibits four glcosylation sites as well as human ATIII. The primary structures of bovine and human ATIII were compared: all the residues required for the integrity of the heparin-binding domain are strictly conserved. However, there are differences in the secondary structures of both proteins, bovine and human ATIII.
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Affiliation(s)
- H Mejdoub
- Laboratoire de Biochimie, Centre National de la Recherche Scientifique, Strasbourg, France
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