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Santos Gomes MMOD, Nicodemos IS, Costa Silva MD, Santos DMRCD, Santos Costa F, Franco M, Pereira HJV. Optimization of enzymatic saccharification of industrial wastes using a thermostable and halotolerant endoglucanase through Box-Behnken experimental design. Prep Biochem Biotechnol 2024; 54:1-11. [PMID: 37071540 DOI: 10.1080/10826068.2023.2201936] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [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] [Indexed: 04/19/2023]
Abstract
This study describes the production, characterization and application of an endoglucanase from Penicillium roqueforti using lignocellulosic agro-industrial wastes as the substrate during solid-state fermentation. The endoglucanase was generated after culturing with different agro-industrial wastes for 96 h without any pretreatment. The highest activity was obtained at 50 °C and pH 4.0. Additionally, the enzyme showed stability in the temperature and pH ranges of 40-80 °C and 4.0-5.0, respectively. The addition of Ca2+, Zn2+, Mg2+, and Cu2+ increased enzymatic activity. Halotolerance as a characteristic of the enzyme was confirmed when its activity increased by 35% on addition of 2 M NaCl. The endoglucanase saccharified sugarcane bagasse, coconut shell, wheat bran, cocoa fruit shell, and cocoa seed husk. The Box-Behnken design was employed to optimize fermentable sugar production by evaluating the following parameters: time, substrate, and enzyme concentration. Under ideal conditions, 253.19 mg/g of fermentable sugars were obtained following the saccharification of wheat bran, which is 41.5 times higher than that obtained without optimizing. This study presents a thermostable, halotolerant endoglucanase that is resistant to metal ions and organic solvents with the potential to be applied in producing fermentable sugars for manufacturing biofuels from agro-industrial wastes.
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Affiliation(s)
| | | | - Monizy da Costa Silva
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, Brazil
| | | | | | - Marcelo Franco
- Department of Exact Sciences and Technology, State University of Santa Cruz, Ilhéus, Brazil
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Dos Santos CWV, de Souza CB, Da Silva AT, Nascimento JSD, Meireles Grillo LA, Gomes FS, Pereira HJV. Purification and characterization of a new trypsin-like protease from Crotalaria stipularia. Prep Biochem Biotechnol 2023:1-8. [PMID: 38156982 DOI: 10.1080/10826068.2023.2299423] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Proteases are the main enzymes traded worldwide-comprising 60% of the total enzyme market-and are fundamental to the degradation and processing of proteins and peptides. Due to their high commercial demand and biological importance, there is a search for alternative sources of these enzymes. Crotalaria stipularia is highlighted for its agroecological applications, including organic fertilizers, nematode combat, and revegetation of areas contaminated with toxic substances. Considering the pronounced biotechnological functionality of the studied species and the necessity to discover alternative sources of proteases, we investigated the extraction, purification, and characterization of a protease from seeds of the C. stipularia plant. Protease isolation was achieved by three-phase partitioning and single-step molecular exclusion chromatography in Sephacryl S-100, with a final recovery of 47% of tryptic activity. The molecular mass of the isolated enzyme was 40 kDa, demonstrating optimal activities at pH 8.0 and 50 °C. Enzymatic characterization demonstrated that the protease can hydrolyze the specific trypsin substrate, BApNA. This trypsin-like protease had a Km, Vmax, Kcat, and catalytic efficiency constant of 0.01775 mg/mL, 0.1082 mM/min, 3.86 s-1, and 217.46, respectively.
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Affiliation(s)
| | - Cledson Barros de Souza
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | - Antônio Thomás Da Silva
- Institute of Pharmaceutical Science, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | - Josiel Santos do Nascimento
- Institute of Pharmaceutical Science, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | | | - Francis Soares Gomes
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | - Hugo Juarez Vieira Pereira
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
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Ferreira AN, Da Silva AT, Nascimento JSD, Souza CBD, Silva MDC, Grillo LAM, Luz JMRD, Pereira HJV. Production, characterization, and application of a new chymotrypsin-like protease from Pycnoporus sanguineus. BIOCATAL BIOTRANSFOR 2023. [DOI: 10.1080/10242422.2023.2196362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Affiliation(s)
| | | | | | - Cledson Barros de Souza
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, Alagoas, Brazil
| | - Monizy da Costa Silva
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, Alagoas, Brazil
| | | | - José Maria Rodrigues da Luz
- Universidade Federal de Viçosa (UFV), Departamento de Microbiologia, Laboratório de Associações Micorrizicas -LAMIC, Viçosa, Minas Gerais, Brazil
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Silva TP, de Albuquerque FS, Nascimento Ferreira A, Santos DMRCD, Santos TVD, Meneghetti SMP, Franco M, Luz JMRD, Pereira HJV. Dilute acid pretreatment for enhancing the enzymatic saccharification of agroresidues using a Botrytis ricini endoglucanase. Biotechnol Appl Biochem 2023; 70:184-192. [PMID: 35338782 DOI: 10.1002/bab.2341] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 05/26/2021] [Accepted: 03/01/2022] [Indexed: 11/08/2022]
Abstract
The enormous amount of agroindustrial residues generated in Brazil can be used as biomass to produce fermentable sugars. This study compared the pretreatments with different proportions of dilute acid. The method involved pretreatment with 0.5%, 1%, and 1.5% (v/v) sulfuric acid, followed by hydrolysis using the halotolerant and thermostable endoglucanase from Botrytis ricini URM 5627. The physicochemical characterization of plant biomass was performed using XRD, FTIR, and SEM. The pretreatment significantly increased the production of fermentable sugars following enzymatic saccharification from wheat bran, sugarcane bagasse, and rice husk: 153.67%, 91.98%, and 253.21% increment in sugar production; 36.39 mg⋅g-1 ± 1.23, 39.55 mg⋅g-1 ± 1.70, and 42.53 mg⋅g-1 ± 7.61 mg⋅L-1 of glucose; and 3.26 ± 0.35 mg⋅g-1 , 3.61mg⋅g-1 ± 0.74 and 3.59 mg⋅g-1 ± 0.80 of fructose were produced, respectively. In conclusion, biomass should preferably be pretreated before the enzymatic saccharification using B. ricini URM 5627 endoglucanase.
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Affiliation(s)
- Tatielle Pereira Silva
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | - Fabiana Sarmento de Albuquerque
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | - Alexsandra Nascimento Ferreira
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | | | - Thatiane Veríssimo Dos Santos
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | | | - Marcelo Franco
- Department of Exact Sciences and Technology, State University of Santa Cruz (UESC), Ilhéus, Bahia, Brazil
| | - José Maria Rodrigues da Luz
- Institute of Pharmaceutical Science, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
| | - Hugo Juarez Vieira Pereira
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), Maceió, Alagoas, Brazil
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Nogueira LS, Tavares IMDC, Santana NB, Ferrão SPB, Teixeira JM, Costa FS, Silva TP, Pereira HJV, Irfan M, Bilal M, de Oliveira JR, Franco M. Thermostable trypsin-like protease by Penicillium roqueforti secreted in cocoa shell fermentation: Production optimization, characterization, and application in milk clotting. Biotechnol Appl Biochem 2021; 69:2069-2080. [PMID: 34617635 DOI: 10.1002/bab.2268] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [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: 05/20/2021] [Accepted: 09/28/2021] [Indexed: 12/13/2022]
Abstract
The increased demand for cheese and the limited availability of calf rennet justifies the search for milk-clotting enzymes from alternative sources. Trypsin-like protease by Penicillium roqueforti was produced by solid-state fermentation using cocoa shell waste as substrate. The production of a crude enzyme extract that is rich in this enzyme was optimized using a Doehlert-type multivariate experimental design. The biochemical characterization showed that the enzyme has excellent activity and stability at alkaline pH (10-12) and an optimum temperature of 80°C, being stable at temperatures above 60°C. Enzymatic activity was maximized in the presence of Na+ (192%), Co2+ (187%), methanol (153%), ethanol (141%), and hexane (128%). Considering the biochemical characteristics obtained and the milk coagulation activity, trypsin-like protease can be applied in the food industry, such as in milk clotting and in the fabrication of cheeses.
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Affiliation(s)
- Laísa Santana Nogueira
- Department of Rural and Animal Technology, State University of Southwest Bahia, Itapetinga, Bahia, Brazil
| | | | - Nívio Batista Santana
- Department of Rural and Animal Technology, State University of Southwest Bahia, Itapetinga, Bahia, Brazil
| | | | | | | | - Tatielle Pereira Silva
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, Maceió, Alagoas, Brazil
| | | | - Muhammad Irfan
- Department of Biotechnology, University of Sargodha, Sargodha, Punjab, Pakistan
| | - Muhammad Bilal
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huaian, China
| | | | - Marcelo Franco
- Department of Exact Sciences and Technology, State University of Santa Cruz, Ilhéus, Bahia, Brazil
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Silva TP, de Albuquerque FS, Dos Santos CWV, Franco M, Caetano LC, Pereira HJV. Production, purification, characterization and application of a new halotolerant and thermostable endoglucanase of Botrytis ricini URM 5627. Bioresour Technol 2018; 270:263-269. [PMID: 30223157 DOI: 10.1016/j.biortech.2018.09.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [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: 07/26/2018] [Revised: 09/03/2018] [Accepted: 09/04/2018] [Indexed: 06/08/2023]
Abstract
A halotolerant endoglucanase with a molecular mass of 39 kDa was obtained from the solid fermentation of sugarcane bagasse by the fungus Botrytis ricini URM 5627 and isolated using only two purification processes: fractionation with ammonium sulphate and size-exclusion chromatography resulting in an activity of 1289.83 U/mL. After the isolation, biochemical characterizations were performed, giving a temperature of 50 °C and optimum pH of 5. The enzyme was stable at 39-60 °C for 60 min and at a pH of 4-6. The enzymatic activity increased in the presence of Na+, Mn2+, Mg2+ and Zn2+ and decreased in the presence of Ca2+, Cu2+, and Fe2+. The endoglucanase revealed a halotolerant profile since its activity increased proportionally to an increase in NaCl concentration. The maximum activity was reached at 2 M NaCl with a 75% increase in activity. The enzyme had a Km of 0.1299 ± 0.0096 mg/mL and a Vmax of 0.097 ± 0.00121 mol/min/mL. During application in saccharification tests, the enzyme was able to hydrolyse sugarcane bagasse, rice husk, and wheat bran, with the highest production of reducers/fermentable sugars within 24 h of saccharification for wheat bran (137.21 mg/g). Therefore, these properties combined make this isolated enzyme a potential candidate for biotechnological and industrial applications.
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Affiliation(s)
- Tatielle P Silva
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), 57072-900 Maceió, Alagoas, Brazil
| | - Fabiana S de Albuquerque
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), 57072-900 Maceió, Alagoas, Brazil
| | - Cláudio Willian V Dos Santos
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), 57072-900 Maceió, Alagoas, Brazil
| | - Marcelo Franco
- Department of Exact Sciences and Technology, State University of Santa Cruz (UESC), 45654-370 Ilhéus, Bahia, Brazil
| | - Luiz Carlos Caetano
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), 57072-900 Maceió, Alagoas, Brazil
| | - Hugo Juarez Vieira Pereira
- Institute of Chemistry and Biotechnology, Federal University of Alagoas, A. C. Simões Campus, (UFAL), 57072-900 Maceió, Alagoas, Brazil.
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Costa RB, Campana PT, Chambergo FS, Napoleão TH, Paiva PMG, Pereira HJV, Oliva MLV, Gomes FS. Purification and characterization of a lectin with refolding ability from Genipa americana bark. Int J Biol Macromol 2018; 119:517-523. [DOI: 10.1016/j.ijbiomac.2018.07.178] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 07/24/2018] [Accepted: 07/28/2018] [Indexed: 12/29/2022]
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Dos Santos DMRC, de Souza CB, Pereira HJV. Angiotensin converting enzymes in fish venom. Toxicon 2017; 131:63-67. [PMID: 28284848 DOI: 10.1016/j.toxicon.2017.03.003] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 02/15/2017] [Accepted: 03/06/2017] [Indexed: 10/20/2022]
Abstract
Animal venoms are multifaceted mixtures, including proteins, peptides and enzymes produced by animals in defense, predation and digestion. These molecules have been investigated concerning their molecular mechanisms associated and possible pharmacological applications. Thalassophryne nattereri is a small venomous fish inhabiting the northern and northeastern coast of Brazil, and represents a relatively frequent cause of injuries. Its venom causes severe inflammatory response followed frequently by the necrosis of the affected area. Scorpaena plumieri is the most venomous fish in the Brazilian fauna and is responsible for relatively frequent accidents involving anglers and bathers. In humans, its venom causes edema, erythema, ecchymoses, nausea, vomiting, and syncope. Recently, the presence of a type of angiotensin converting enzyme (ACE) activity in the venom of Thalassophryne nattereri and Scorpaena plumieri, endemic fishes in northeastern coast of Brazil, has been described. The ACE converts angiotensin I (Ang I) into angiotensin II (Ang II) and inactivates bradykinin, there by regulating blood pressure and electrolyte homeostasis, however, their function in these venoms remains an unknown. This article provides an overview of the current knowledge on ACE in the venoms of Thalassophryne nattereri and Scorpaena plumier.
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dos Santos CW, da Costa Marques ME, de Araújo Tenório H, de Miranda EC, Vieira Pereira HJ. Purification and characterization of trypsin from Luphiosilurus alexandri pyloric cecum. Biochem Biophys Rep 2016; 8:29-33. [PMID: 28955938 PMCID: PMC5613698 DOI: 10.1016/j.bbrep.2016.08.003] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 06/28/2016] [Accepted: 08/02/2016] [Indexed: 11/26/2022] Open
Abstract
Trypsin from L. alexandri was purified using only two purification processes: ammonium sulfate precipitation and anion exchange liquid chromatography in DEAE-Sepharose. Trypsin mass was estimated as 24 kDa through SDS-PAGE, which showed only one band in silver staining. The purified enzyme showed an optimum temperature and pH of 50 °C and 9.0, respectively. Stability was well maintained, with high levels of activity at a pH of up to 11.0, including high stability at a temperature of up to 50 °C after 60 min of incubation. The inhibition test demonstrated strong inhibition by PMSF, a serine protease inhibitor, and Kinetic constants km and kcat for BAPNA were 0.517 mM and 5.0 S-1, respectively. The purified enzyme was also as active as casein, as analyzed by zymography. Therefore, we consider trypsin a promising enzyme for industrial processes, owing to its stability in a wide range of pH and temperature and activity even under immobilization.
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Affiliation(s)
| | | | | | | | - Hugo Juarez Vieira Pereira
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Avenida Lourival Melo Mota, s/n, 57072-970 Maceió, AL, Brazil
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da Costa Marques ME, de Araújo Tenório H, dos Santos CWV, dos Santos DM, de Lima ME, Pereira HJV. Angiotensin converting enzyme of Thalassophryne nattereri venom. Int J Biol Macromol 2016; 91:980-6. [DOI: 10.1016/j.ijbiomac.2016.06.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 06/14/2016] [Accepted: 06/16/2016] [Indexed: 12/23/2022]
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Tenório HDA, Costa RB, Costa Marques ME, Victor Dos Santos CW, Gomes FS, Vieira Pereira HJ. Angiotensins processing activities in the venom and epidermic mucus of Scorpaena plumieri. Toxicon 2016; 119:92-8. [PMID: 27215174 DOI: 10.1016/j.toxicon.2016.05.008] [Citation(s) in RCA: 4] [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: 04/18/2016] [Revised: 05/05/2016] [Accepted: 05/18/2016] [Indexed: 11/16/2022]
Abstract
The venom of marine animals is a rich source of compounds with remarkable selectivity and functional diversity. Scorpaena plumieri is the most venomous fish in the Brazilian fauna and is responsible for relatively frequent accidents involving anglers and bathers. In humans, its venom causes edema, erythema, ecchymoses, anxiety, nausea, vomiting, and syncope. The venom is chemically characterized by Sp-CTx, a enzyme able to generate an initial endothelium-dependent relaxation response, followed by a contraction response. This study sought to investigate the proteolytic activities regarding vasopeptides angiotensin I and II. Both the venom and the epidermal mucus presented angiotensin conversion activity for angiotensin I, as well as a capacity to form Ang 1-7 directly via Ang I and II. Captopril (10 μM) and EDTA (1 mM) were able to abolish the converting activity of the venom and the epidermal mucus, representing the first description of a converting activity in S. plumieri venom and epidermal mucus.
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Affiliation(s)
| | - Ricardo Bezerra Costa
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Maceió, Brazil
| | | | | | - Francis Soares Gomes
- Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, Maceió, Brazil
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Tenório HDA, da Costa Marques ME, Machado SS, Pereira HJV. Angiotensin processing activities in the venom of Thalassophryne nattereri. Toxicon 2015; 98:49-53. [DOI: 10.1016/j.toxicon.2015.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/10/2015] [Accepted: 02/18/2015] [Indexed: 11/25/2022]
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Pereira HJV, Salgado MCO, Oliveira EB. Immobilized analogues of sunflower trypsin inhibitor-1 constitute a versatile group of affinity sorbents for selective isolation of serine proteases. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:2039-44. [DOI: 10.1016/j.jchromb.2009.05.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Revised: 04/07/2009] [Accepted: 05/18/2009] [Indexed: 11/26/2022]
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Santos CF, Akashi AE, Dionísio TJ, Sipert CR, Didier DN, Greene AS, Oliveira SHP, Pereira HJV, Becari C, Oliveira EB, Salgado MCO. Characterization of a local renin-angiotensin system in rat gingival tissue. J Periodontol 2009; 80:130-9. [PMID: 19228099 DOI: 10.1902/jop.2009.080264] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND The systemic renin-angiotensin system (RAS) promotes the plasmatic production of angiotensin (Ang) II, which acts through interaction with specific receptors. There is growing evidence that local systems in various tissues and organs are capable of generating angiotensins independently of circulating RAS. The aims of this study were to investigate the expression and localization of RAS components in rat gingival tissue and evaluate the in vitro production of Ang II and other peptides catalyzed by rat gingival tissue homogenates incubated with different Ang II precursors. METHODS Reverse transcription-polymerase chain reaction assessed mRNA expression. Immunohistochemical analysis aimed to detect and localize renin. A standardized fluorimetric method with tripeptide hippuryl-histidyl-leucine was used to measure tissue angiotensin-converting enzyme (ACE) activity, whereas high performance liquid chromatography showed products formed after the incubation of tissue homogenates with Ang I or tetradecapeptide renin substrate (TDP). RESULTS mRNA for renin, angiotensinogen, ACE, and Ang II receptors (AT(1a), AT(1b), and AT(2)) was detected in gingival tissue; cultured gingival fibroblasts expressed renin, angiotensinogen, and AT(1a) receptor. Renin was present in the vascular endothelium and was intensely expressed in the epithelial basal layer of periodontally affected gingival tissue. ACE activity was detected (4.95 +/- 0.89 nmol histidyl-leucine/g/minute). When Ang I was used as substrate, Ang 1-9 (0.576 +/- 0.128 nmol/mg/minute), Ang II (0.066 +/- 0.008 nmol/mg/minute), and Ang 1-7 (0.111 +/- 0.017 nmol/mg/minute) were formed, whereas these same peptides (0.139 +/- 0.031, 0.206 +/- 0.046, and 0.039 +/- 0.007 nmol/mg/minute, respectively) and Ang I (0.973 +/- 0.139 nmol/mg/minute) were formed when TDP was the substrate. CONCLUSION Local RAS exists in rat gingival tissue and is capable of generating Ang II and other vasoactive peptides in vitro.
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Affiliation(s)
- C F Santos
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil
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