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Initial biophysical characterization of Amynthas gracilis giant extracellular hemoglobin (HbAg). EUROPEAN BIOPHYSICS JOURNAL: EBJ 2020; 49:473-484. [PMID: 32813035 DOI: 10.1007/s00249-020-01455-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 08/01/2020] [Accepted: 08/11/2020] [Indexed: 10/23/2022]
Abstract
The aim of the present work was the biophysical characterization of the Amynthas gracilis hemoglobin (HbAg). The oxy-HbAg optical absorption data, with Soret and Q bands centered at 415, 540 and 575 nm, were stable and unchanged at pH 7.0. An increase in pH promotes decrease in the intensity in the optical absorption bands, suggesting an oligomeric dissociation and partial oxidation. Identical stability at pH 7.0 was observed in DLS results that presented a hydrodynamic diameter of 28 nm, characteristic of the whole oligomer. DLS shows that HbAg undergoes oligomeric dissociation and an aggregation/denaturation process that corroborates spectroscopic data. Our results showed that the monomer d presents four isoforms with molecular mass (MM) ranging from 16,244 to 16,855 Da; the trimer subunit presents two isoforms, (abc)1 and (abc)2, with MM of 51,415 ± 20 Da and 51,610 ± 14 Da, respectively, and a less intense species, at 67,793 Da, assigned to the tetramer abcd. Monomeric chains a, obtained from reduction of the disulfide-bonded trimer abc, present four isoforms with MM 17,015 Da, 17,061 Da, 17,138 Da and 17,259 Da. DLS and LSI revealed an isoeletric point (pI) of oxy-HbAg of 6.0 ± 0.3 and 5.5, respectively. Data analysis by IEF-SDS-PAGE revealed that the pI of oxy-HbAg is 6.11, correlating with DLS and LSI data. These studies indicate that oxy-HbAg is very stable, at pH 7.0, and has differing properties from orthologous giant hemoglobins.
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2
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Carvalho FAO, Caruso CS, Nascimento ED, Oliveira TMBF, Bachega JFR, Tabak M. Oligomeric stability of Glossoscolex paulistus hemoglobin as a function of the storage time. Int J Biol Macromol 2019; 133:30-36. [PMID: 30986471 DOI: 10.1016/j.ijbiomac.2019.04.072] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 04/11/2019] [Accepted: 04/11/2019] [Indexed: 11/16/2022]
Abstract
Glossoscolex paulistus hemoglobin structure is composed of 144 globin chains and 36 polypeptide chains lacking the heme group, with a total molecular mass of 3600 kDa. The current study focuses on the oxy-HbGp oligomeric stability, as a function of the storage time, at pH 7.0, using dynamic light scattering, analytical ultracentrifugation (AUC), optical absorption and size exclusion chromatography (SEC). HbGp stored in Tris-HCl buffer, pH 7.0, at 4 °C, for two years remains in the native form, while 4-6 years HbGp stocks present typical hemichrome species absorption spectra. AUC and SEC analyses show that the contribution of HbGp-subunits, such as, dodecamer (abcd)3, tetramer abcd, trimer abc and monomer d, increases with the protein aging due to the lower stability of the HbGp with the time. The dissociation and the oxidation of the iron noted for the older protein solutions indicate that HbGp storage for periods of time longer than two years changes its ability to carry oxygen. Despite the reduction of HbGp stability and oxygen carrying capacity with aging, the protein stability is still larger as compared to mammalian hemoglobins. Thus, the extracellular hemoglobins are quite stable and resistant to the auto-oxidation process, making them of interest for biotechnological applications.
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Affiliation(s)
| | - Celia S Caruso
- Instituto de Química de São Carlos - Universidade de São Paulo, Brazil
| | - Evair D Nascimento
- Instituto de Ciências Exatas - Universidade Federal do Sul e Sudeste do Pará, Brazil
| | - Thiago Mielle B F Oliveira
- Centro de Ciência e Tecnologia, Universidade Federal do Cariri, Av. Tenente Raimundo Rocha, Cidade Universitária, 63048-080 Juazeiro do Norte, CE, Brazil
| | - José F R Bachega
- Universidade Federal de Ciências da Saúde de Porto Alegre - UFCSPA, Brazil
| | - Marcel Tabak
- Instituto de Química de São Carlos - Universidade de São Paulo, Brazil
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3
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Caruso CS, Biazin E, Carvalho FA, Tabak M, Bachega JF. Metals content of Glossoscolex paulistus extracellular hemoglobin: Its peroxidase activity and the importance of these ions in the protein stability. J Inorg Biochem 2016; 161:63-72. [DOI: 10.1016/j.jinorgbio.2016.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 04/08/2016] [Accepted: 05/04/2016] [Indexed: 10/21/2022]
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4
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Carvalho FAO, Alves FR, Tabak M. Ionic surfactants-Glossoscolex paulistus hemoglobin interactions: Characterization of species in the solution. Int J Biol Macromol 2016; 92:670-681. [PMID: 27456123 DOI: 10.1016/j.ijbiomac.2016.07.072] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 07/18/2016] [Accepted: 07/21/2016] [Indexed: 12/18/2022]
Abstract
Glossoscolex paulistus hemoglobin (HbGp) is an oligomeric multisubunit protein with molecular mass of 3600kDa. In the current study, the interaction of sodium dodecyl sulfate (SDS) and cetyl trimethylammonium chloride (CTAC) surfactants with the monomer d and the whole oxy-HbGp, at pH 7.0, was investigated. For pure monomer d solution, SDS promotes the dimerization of subunit d, and the monomeric and dimeric forms have sedimentation coefficient values, s20,w, around 2.1-2.4 S and 2.9-3.2 S, respectively. Analytical ultracentrifugation (AUC) and isothermal titration calorimetry (ITC) data suggest that up to 26 DS- anions are bound to the monomer. In the presence of CTAC, only the monomeric form is observed in solution for subunit d. For the oxy-HbGp, SDS induces the dissociation into smaller subunits, such as, monomer d, trimer abc, and tetramer abcd, and unfolding without promoting the protein aggregation. On the other hand, lower CTAC concentration promotes protein aggregation, mainly of trimer, while higher concentration induces the unfolding of dissociated species. Our study provides strong evidence that surfactant effects upon the HbGp-subunits are different, and depend on the surfactant: protein concentration ratio and the charges of surfactant headgroups.
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Affiliation(s)
- Francisco A O Carvalho
- Instituto de Química de São Carlos, Universidade de São Paulo, Brazil; Faculdade de Química, Universidade Federal do Sul e Sudeste do Pará, Brazil.
| | - Fernanda R Alves
- Instituto de Química de São Carlos, Universidade de São Paulo, Brazil
| | - Marcel Tabak
- Instituto de Química de São Carlos, Universidade de São Paulo, Brazil
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Carvalho JWP, Carvalho FAO, Santiago PS, Tabak M. Thermal stability of extracellular hemoglobin of Rhinodrilus alatus (HbRa): DLS and SAXS studies. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2016; 45:549-63. [DOI: 10.1007/s00249-016-1121-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Revised: 02/02/2016] [Accepted: 02/20/2016] [Indexed: 10/22/2022]
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6
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Alves FR, Carvalho FAO, Carvalho JWP, Tabak M. Interaction of cationic dodecyl-trimethyl-ammonium bromide with oxy-HbGp by isothermal titration and differential scanning calorimetric studies: Effect of proximity of isoelectric point. Biopolymers 2015; 105:199-211. [PMID: 26574155 DOI: 10.1002/bip.22777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 11/03/2015] [Accepted: 11/04/2015] [Indexed: 11/10/2022]
Abstract
In this work, isothermal titration and differential scanning calorimetric methods, in combination with pyrene fluorescence emission and dynamic light scattering have been used to investigate the interaction of dodecyltrimethylammonium bromide (DTAB) with the giant extracellular Glossoscolex paulistus hemoglobin (HbGp) in the oxy-form, at pH values around the isoelectric point (pI ≈ 5.5). Our ITC results have shown that the interaction of DTAB with the hemoglobin is more intense at pH 7.0, with a smaller cac (critical aggregation concentration) value. The increase of protein concentration does not influence the cac value of the interaction, at both pH values. Therefore, the beginning of the DTAB-oxy-HbGp premicellar aggregates formation, in the cac region, is not affected by the increase of protein concentration. HSDSC studies show higher Tm values at pH 5.0, in the absence and presence of DTAB, when compared with pH 7.0. Furthermore, at pH 7.0, an aggregation process is observed with DTAB in the range from 0.75 to 1.5 mmol/L, noticed by the exothermic peak, and similar to that observed for pure oxy-HbGp, at pH 5.0, and in the presence of DTAB. DLS melting curves show a decrease on the hemoglobin thermal stability for the oxy-HbGp-DTAB mixtures and formation of larger aggregates, at pH 7.0. Our present data, together with previous results, support the observation that the protein structural changes, at pH 7.0, occur at smaller DTAB concentrations, as compared with pH 5.0, due to the acidic pI of protein that favors the oxy-HbGp-cationic surfactant interaction at neutral pH.
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Affiliation(s)
- Fernanda Rosa Alves
- Instituto De Química De São Carlos, Universidade De São Paulo, São Carlos, SP, Brazil
| | | | | | - Marcel Tabak
- Instituto De Química De São Carlos, Universidade De São Paulo, São Carlos, SP, Brazil
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7
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Ruggiero Bachega JF, Vasconcelos Maluf F, Andi B, D'Muniz Pereira H, Falsarella Carazzollea M, Orville AM, Tabak M, Brandão-Neto J, Garratt RC, Horjales Reboredo E. The structure of the giant haemoglobin from Glossoscolex paulistus. ACTA ACUST UNITED AC 2015; 71:1257-71. [PMID: 26057666 DOI: 10.1107/s1399004715005453] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 03/16/2015] [Indexed: 11/10/2022]
Abstract
The sequences of all seven polypeptide chains from the giant haemoglobin of the free-living earthworm Glossoscolex paulistus (HbGp) are reported together with the three-dimensional structure of the 3.6 MDa complex which they form. The refinement of the full particle, which has been solved at 3.2 Å resolution, the highest resolution reported to date for a hexagonal bilayer haemoglobin composed of 12 protomers, is reported. This has allowed a more detailed description of the contacts between subunits which are essential for particle stability. Interpretation of features in the electron-density maps suggests the presence of metal-binding sites (probably Zn(2+) and Ca(2+)) and glycosylation sites, some of which have not been reported previously. The former appear to be important for the integrity of the particle. The crystal structure of the isolated d chain (d-HbGp) at 2.1 Å resolution shows different interchain contacts between d monomers compared with those observed in the full particle. Instead of forming trimers, as seen in the complex, the isolated d chains associate to form dimers across a crystallographic twofold axis. These observations eliminate the possibility that trimers form spontaneously in solution as intermediates during the formation of the dodecameric globin cap and contribute to understanding of the possible ways in which the particle self-assembles.
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Affiliation(s)
| | | | - Babak Andi
- Photon Sciences Directorate, Brookhaven National Laboratory, Upton, New York, USA
| | | | - Marcelo Falsarella Carazzollea
- Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil
| | - Allen M Orville
- Photon Sciences Directorate, Brookhaven National Laboratory, Upton, New York, USA
| | - Marcel Tabak
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, Brazil
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8
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Barros AE, Carvalho FA, Alves FR, Carvalho JW, Tabak M. Denaturant effects on HbGp hemoglobin as monitored by 8-anilino-1-naphtalene-sulfonic acid (ANS) probe. Int J Biol Macromol 2015; 74:327-36. [DOI: 10.1016/j.ijbiomac.2014.12.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 12/17/2014] [Accepted: 12/18/2014] [Indexed: 10/24/2022]
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9
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Carvalho FAO, Alves FR, Carvalho JWP, Tabak M. Guanidine hydrochloride and urea effects upon thermal stability of Glossoscolex paulistus hemoglobin (HbGp). Int J Biol Macromol 2014; 74:18-28. [PMID: 25433131 DOI: 10.1016/j.ijbiomac.2014.11.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 11/17/2014] [Accepted: 11/19/2014] [Indexed: 11/16/2022]
Abstract
Glossoscolex paulistus hemoglobin (HbGp) has a molecular mass of 3600kDa. It belongs to the hexagonal bilayer hemoglobin class, which consists of highly cooperative respiratory macromolecules found in mollusks and annelids. The present work focusses on oxy-HbGp thermal stability, in the presence of urea and guanidine hydrochloride (GuHCl), monitored by several techniques. Initially, dynamic light scattering data show that the presence of GuHCl induces the protein oligomeric dissociation, followed by a significant 11-fold increase in the hydrodynamic diameter (DH) values, due to the formation of protein aggregates in solution. In contrast, urea promotes the HbGp oligomeric dissociation, followed by unfolding process at high temperatures, without aggregation. Circular dichroism data show that unfolding critical temperature (Tc) of oxy-HbGp decreases from 57°C, at 0.0 mol/L of the denaturant, to 45°C, in the presence of 3.5 mol/L of urea, suggesting the reduction of HbGp oligomeric stability. Moreover, differential scanning calorimetry results show that at lower GuHCl concentrations, some thermal stabilization of the hemoglobin is observed, whereas at higher concentrations, the reduction of stability takes place. Besides, HbGp is more stable in the presence of urea when compared with the guanidine effect, as deduced from the differences in the concentration range of denaturants.
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Affiliation(s)
| | - Fernanda R Alves
- Instituto de Química de São Carlos-Universidade de São Paulo, Brazil
| | - José W P Carvalho
- Instituto de Química de São Carlos-Universidade de São Paulo, Brazil; Universidade do Estado de Mato Grosso, MT, Brazil
| | - Marcel Tabak
- Instituto de Química de São Carlos-Universidade de São Paulo, Brazil
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Characterization of Rhinodrilus alatus hemoglobin (HbRa) and its subunits: Evidence for strong interaction with cationic surfactants DTAB and CTAC. Comp Biochem Physiol B Biochem Mol Biol 2014; 167:23-9. [DOI: 10.1016/j.cbpb.2013.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 09/23/2013] [Accepted: 09/23/2013] [Indexed: 11/15/2022]
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11
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Carvalho FAO, Carvalho JWP, Alves FR, Tabak M. pH effect upon HbGp oligomeric stability: characterization of the dissociated species by AUC and DLS studies. Int J Biol Macromol 2013; 59:333-41. [DOI: 10.1016/j.ijbiomac.2013.04.070] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 04/24/2013] [Accepted: 04/25/2013] [Indexed: 10/26/2022]
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12
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Carvalho JWP, Carvalho FA, Santiago PS, Tabak M. Thermal denaturation and aggregation of hemoglobin of Glossoscolex paulistus in acid and neutral media. Int J Biol Macromol 2013. [DOI: 10.1016/j.ijbiomac.2012.11.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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13
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Carvalho FA, Carvalho JWP, Santiago PS, Tabak M. Urea-induced unfolding of Glossoscolex paulistus hemoglobin, in oxy- and cyanomet-forms: A dissociation model. Int J Biol Macromol 2013; 52:340-8. [DOI: 10.1016/j.ijbiomac.2012.09.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 09/22/2012] [Accepted: 09/25/2012] [Indexed: 10/27/2022]
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14
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Carvalho FAO, Santiago PS, Tabak M. On the stability of the extracellular hemoglobin of Glossoscolex paulistus, in two iron oxidation states, in the presence of urea. Arch Biochem Biophys 2012; 519:46-58. [DOI: 10.1016/j.abb.2012.01.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 01/04/2012] [Accepted: 01/10/2012] [Indexed: 01/04/2023]
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15
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Moreira LM, Poli AL, Lyon JP, Aimbire F, Toledo JC, Costa-Filho AJ, Imasato H. Ligand changes in ferric species of the giant extracellular hemoglobin of Glossoscolex paulistusas function of pH: correlations between redox, spectroscopic and oligomeric properties and general implications with different hemoproteins. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s108842461000201x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The present review is focused on the relationship between oligomeric and heme properties of HbGp, emphasizing the characteristics that can be generalized to other hemoproteins. This study represents the state-of-the-art with respect to the approaches for investigating giant extracellular hemoglobins as well as the correlation between oligomeric assembly alterations and their consequent changes in the first coordination sphere. A wide introduction focused on the properties of this hemoglobin is developed. Indeed, this hemoprotein is considered an interesting prototype of blood substitute and biosensor due to its peculiar properties, such as resistance to autoxidation and oligomeric stability. Previous studies by our group employing UV-vis, EPR and CD spectroscopies have been revised in a complete approach, in agreement with recent and relevant data from the literature. In fact, a consistent and inter-related spectroscopic study is described propitiating a wide assignment of "fingerprint" peaks found in the techniques evaluated in this paper. This review furnishes physicochemical information regarding the identification of ferric heme species of hemoproteins and metallic complexes through their spectroscopic bands. This effort at the attribution of UV-vis, EPR and CD peaks is not restricted to HbGp, and includes a comparative analysis of several hemoproteins involving relevant implications regarding several types of iron-porphyrin systems.
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Affiliation(s)
- Leonardo Marmo Moreira
- Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraíba, 12244-000 São José dos Campos SP, Brazil
- Instituto de Química de São Carlos, Universidade de São Paulo, 13560-970 São Carlos SP, Brazil
- Instituto de Pesquisa e Qualidade Acadêmica (IPQA), Universidade Camilo Castelo Branco, São José dos Campos SP, Brazil
| | - Alessandra Lima Poli
- Instituto de Química de São Carlos, Universidade de São Paulo, 13560-970 São Carlos SP, Brazil
| | - Juliana Pereira Lyon
- Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraíba, 12244-000 São José dos Campos SP, Brazil
| | - Flávio Aimbire
- Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraíba, 12244-000 São José dos Campos SP, Brazil
- Instituto de Pesquisa e Qualidade Acadêmica (IPQA), Universidade Camilo Castelo Branco, São José dos Campos SP, Brazil
| | | | | | - Hidetake Imasato
- Instituto de Química de São Carlos, Universidade de São Paulo, 13560-970 São Carlos SP, Brazil
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Further characterization of the subunits of the giant extracellular hemoglobin of Glossoscolex paulistus (HbGp) by SDS-PAGE electrophoresis and MALDI-TOF-MS. Process Biochem 2011. [DOI: 10.1016/j.procbio.2011.08.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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17
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Carvalho FAO, Santiago PS, Borges JC, Tabak M. Molecular masses and sedimentation coefficients of extracellular hemoglobin of Glossoscolex paulistus: Alkaline oligomeric dissociation. Int J Biol Macromol 2011; 48:183-93. [DOI: 10.1016/j.ijbiomac.2010.11.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 10/29/2010] [Accepted: 11/04/2010] [Indexed: 10/18/2022]
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18
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Wang X, Chang L, Sun Z, Zhang Y, Yao L. Analysis of earthworm Eisenia fetida
proteomes during cadmium exposure: An ecotoxicoproteomics approach. Proteomics 2010; 10:4476-90. [DOI: 10.1002/pmic.201000209] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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19
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Thermal stability of extracellular hemoglobin of Glossoscolex paulistus: determination of activation parameters by optical spectroscopic and differential scanning calorimetric studies. Biophys Chem 2010; 152:128-38. [PMID: 20875698 DOI: 10.1016/j.bpc.2010.08.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 08/24/2010] [Accepted: 08/31/2010] [Indexed: 11/20/2022]
Abstract
Glossoscolex paulistus hemoglobin (HbGp) was studied by dynamic light scattering (DLS), optical absorption spectroscopy (UV-VIS) and differential scanning calorimetry (DSC). At pH 7.0, cyanomet-HbGp is very stable, no oligomeric dissociation is observed, while denaturation occurs at 56°C, 4°C higher as compared to oxy-HbGp. The oligomeric dissociation of HbGp occurs simultaneously with some protein aggregation. Kinetic studies for oxy-HbGp using UV-VIS and DLS allowed to obtain activation energy (E(a)) values of 278-262 kJ/mol (DLS) and 333 kJ/mol (UV-VIS). Complimentary DSC studies indicate that the denaturation is irreversible, giving endotherms strongly dependent upon the heating scan rates, suggesting a kinetically controlled process. Dependence on protein concentration suggests that the two components in the endotherms are due to oligomeric dissociation effect upon denaturation. Activation energies are in the range 200-560 kJ/mol. The mid-point transition temperatures were in the range 50-65 °C. Cyanomet-HbGp shows higher mid-point temperatures as well as activation energies, consistent with its higher stability. DSC data are reported for the first time for an extracellular hemoglobin.
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Carvalho FAO, Santiago PS, Borges JC, Tabak M. On the molecular mass of the extracellular hemoglobin of Glossoscolex paulistus: Analytical ultracentrifugation reexamination. Anal Biochem 2009; 385:257-63. [DOI: 10.1016/j.ab.2008.11.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 11/06/2008] [Accepted: 11/06/2008] [Indexed: 11/29/2022]
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21
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Moreira LM, Poli AL, Lyon JP, Saade J, Costa-Filho AJ, Imasato H. Ferric species of the giant extracellular hemoglobin of Glossoscolex paulistus as function of pH: An EPR study on the irreversibility of the heme transitions. Comp Biochem Physiol B Biochem Mol Biol 2008; 150:292-300. [DOI: 10.1016/j.cbpb.2008.03.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2008] [Revised: 03/19/2008] [Accepted: 03/21/2008] [Indexed: 10/22/2022]
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22
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Oliveira MS, Moreira LM, Tabak M. Interaction of giant extracellular Glossoscolex paulistus hemoglobin (HbGp) with ionic surfactants: A MALDI-TOF-MS study. Int J Biol Macromol 2008; 42:111-9. [DOI: 10.1016/j.ijbiomac.2007.10.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 10/03/2007] [Accepted: 10/03/2007] [Indexed: 10/22/2022]
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23
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Moreira LM, Poli AL, Costa-Filho AJ, Imasato H. Ferric species equilibrium of the giant extracellular hemoglobin of Glossoscolex paulistus in alkaline medium: HALS hemichrome as a precursor of pentacoordinate species. Int J Biol Macromol 2008; 42:103-10. [DOI: 10.1016/j.ijbiomac.2007.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Revised: 09/10/2007] [Accepted: 10/01/2007] [Indexed: 11/25/2022]
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24
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Moreira LM, Santiago PS, de Almeida EV, Tabak M. Interaction of giant extracellular Glossoscolex paulistus hemoglobin (HbGp) with zwitterionic surfactant N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (HPS): Effects of oligomeric dissociation. Colloids Surf B Biointerfaces 2008; 61:153-63. [PMID: 17825537 DOI: 10.1016/j.colsurfb.2007.07.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2007] [Revised: 07/27/2007] [Accepted: 07/28/2007] [Indexed: 10/23/2022]
Abstract
The present work focuses on the interaction between the zwitterionic surfactant N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (HPS) and the giant extracellular hemoglobin of Glossoscolex paulistus (HbGp). Electronic optical absorption, fluorescence emission and circular dichroism spectroscopy techniques, together with Gel-filtration chromatography, were used in order to evaluate the oligomeric dissociation as well as the autoxidation of HbGp as a function of the interaction with HPS. A peculiar behavior was observed for the HPS-HbGp interaction: a complex ferric species formation equilibrium was promoted, as a consequence of the autoxidation and oligomeric dissociation processes. At pH 7.0, HPS is more effective up to 1mM while at pH 9.0 the surfactant effect is more intense above 1mM. Furthermore, the interaction of HPS with HbGp was clearly less intense than the interaction of this hemoglobin with cationic (CTAC) and anionic (SDS) surfactants. Probably, this lower interaction with HPS is due to two factors: (i) the lower electrostatic attraction between the HPS surfactant and the protein surface ionic sites when compared to the electrostatic interaction between HbGp and cationic and anionic surfactants, and (ii) the low cmc of HPS, which probably reduces the interaction of the surfactant in the monomeric form with the protein. The present work emphasizes the importance of the electrostatic contribution in the interaction between ionic surfactants and HbGp. Furthermore, in the whole HPS concentration range used in this study, no folding and autoxidation decrease induced by this surfactant were observed. This is quite different from the literature data on the interaction between surfactants and tetrameric hemoglobins, that supports the occurrence of this behavior for the intracellular hemoglobins at low surfactant concentration range. Spectroscopic data are discussed and compared with the literature in order to improve the understanding of hemoglobin-surfactant interaction as well as the acid isoelectric point (pI) influence of the giant extracellular hemoglobins on their structure-activity relationship.
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Affiliation(s)
- Leonardo M Moreira
- Instituto de Química de São Carlos, Universidade de São Paulo, 13560-970 São Carlos, SP, Brazil
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Dynamic light scattering and optical absorption spectroscopy study of pH and temperature stabilities of the extracellular hemoglobin of Glossoscolex paulistus. Biophys J 2007; 94:2228-40. [PMID: 18065453 DOI: 10.1529/biophysj.107.116780] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The extracellular hemoglobin of Glossoscolex paulistus (HbGp) is constituted of subunits containing heme groups, monomers and trimers, and nonheme structures, called linkers, and the whole protein has a minimum molecular mass near 3.1 x 10(6) Da. This and other proteins of the same family are useful model systems for developing blood substitutes due to their extracellular nature, large size, and resistance to oxidation. HbGp samples were studied by dynamic light scattering (DLS). In the pH range 6.0-8.0, HbGp is stable and has a monodisperse size distribution with a z-average hydrodynamic diameter (D(h)) of 27 +/- 1 nm. A more alkaline pH induced an irreversible dissociation process, resulting in a smaller D(h) of 10 +/- 1 nm. The decrease in D(h) suggests a complete hemoglobin dissociation. Gel filtration chromatography was used to show unequivocally the oligomeric dissociation observed at alkaline pH. At pH 9.0, the dissociation kinetics is slow, taking a minimum of 24 h to be completed. Dissociation rate constants progressively increase at higher pH, becoming, at pH 10.5, not detectable by DLS. Protein temperature stability was also pH-dependent. Melting curves for HbGp showed oligomeric dissociation and protein denaturation as a function of pH. Dissociation temperatures were lower at higher pH. Kinetic studies were also performed using ultraviolet-visible absorption at the Soret band. Optical absorption monitors the hemoglobin autoxidation while DLS gives information regarding particle size changes in the process of protein dissociation. Absorption was analyzed at different pH values in the range 9.0-9.8 and at two temperatures, 25 degrees C and 38 degrees C. At 25 degrees C, for pH 9.0 and 9.3, the kinetics monitored by ultraviolet-visible absorption presents a monoexponential behavior, whereas for pH 9.6 and 9.8, a biexponential behavior was observed, consistent with heme heterogeneity at more alkaline pH. The kinetics at 38 degrees C is faster than that at 25 degrees C and is biexponential in the whole pH range. DLS dissociation rates are faster than the autoxidation dissociation rates at 25 degrees C. Autoxidation and dissociation processes are intimately related, so that oligomeric protein dissociation promotes the increase of autoxidation rate and vice versa. The effect of dissociation is to change the kinetic character of the autoxidation of hemes from monoexponential to biexponential, whereas the reverse change is not as effective. This work shows that DLS can be used to follow, quantitatively and in real time, the kinetics of changes in the oligomerization of biologic complex supramolecular systems. Such information is relevant for the development of mimetic systems to be used as blood substitutes.
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