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Palma AS, Casadei BR, Lotierzo MC, de Castro RD, Barbosa LRS. A short review on the applicability and use of cubosomes as nanocarriers. Biophys Rev 2023; 15:553-567. [PMID: 37681099 PMCID: PMC10480096 DOI: 10.1007/s12551-023-01089-y] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 06/28/2023] [Indexed: 09/09/2023] Open
Abstract
Abstract Cubosomes are nanostructured lipid-based particles that have gained significant attention in the field of drug delivery and nanomedicine. These unique structures consist of a three-dimensional cubic lattice formed by the self-assembly of lipid molecules. The lipids used to construct cubosomes are typically nonionic surfactants, such as monoolein, which possess both hydrophilic and hydrophobic regions, allowing them to form stable, water-dispersible nanoparticles. One of the key advantages of cubosomes is their ability to encapsulate and deliver hydrophobic as well as hydrophilic drugs. The hydrophobic regions of the lipid bilayers provide an ideal environment for incorporating lipophilic drugs, while the hydrophilic regions can encapsulate water-soluble drugs. This versatility makes cubosomes suitable for delivering a wide range of therapeutic agents, including small molecules, proteins, peptides, and nucleic acids. The unique structure of cubosomes also offers stability and controlled release benefits. The lipid bilayers provide a protective barrier, shielding the encapsulated drugs from degradation and improving their stability. Moreover, the cubic lattice arrangement enables the modulation of drug release kinetics by varying the lipid composition and surface modifications. This allows for the development of sustained or triggered drug release systems, enhancing therapeutic efficacy and reducing side effects. Furthermore, cubosomes can be easily modified with targeting ligands or surface modifications to achieve site-specific drug delivery, enhancing therapeutic selectivity and reducing off-target effects. In conclusion, cubosomes offer a versatile and promising platform for the delivery of therapeutic agents. In this manuscript, we will highlight some of these applications. Graphical abstract
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Affiliation(s)
- Amanda Santos Palma
- Institute of Physics, University of São Paulo, USP, São Paulo, SP 05508-090 Brazil
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP 13083-100 Brazil
| | - Bruna Renata Casadei
- Institute of Physics, University of São Paulo, USP, São Paulo, SP 05508-090 Brazil
| | - Mayra Cristina Lotierzo
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, USP, São Paulo, SP 05508-000 Brazil
| | - Raphael Dias de Castro
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, USP, São Paulo, SP 05508-000 Brazil
| | - Leandro Ramos Souza Barbosa
- Institute of Physics, University of São Paulo, USP, São Paulo, SP 05508-090 Brazil
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP 13083-100 Brazil
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de Souza Guimarães M, Cachumba JJM, Bueno CZ, Torres-Obreque KM, Lara GVR, Monteiro G, Barbosa LRS, Pessoa A, Rangel-Yagui CDO. Peg-Grafted Liposomes for L-Asparaginase Encapsulation. Pharmaceutics 2022; 14:1819. [PMID: 36145567 PMCID: PMC9503594 DOI: 10.3390/pharmaceutics14091819] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/17/2022] [Accepted: 08/24/2022] [Indexed: 11/17/2022] Open
Abstract
L-asparaginase (ASNase) is an important biological drug used to treat Acute Lymphoblastic Leukemia (ALL). It catalyzes the hydrolysis of L-asparagine (Asn) in the bloodstream and, since ALL cells cannot synthesize Asn, protein synthesis is impaired leading to apoptosis. Despite its therapeutic importance, ASNase treatment is associated to side effects, mainly hypersensitivity and immunogenicity. Furthermore, degradation by plasma proteases and immunogenicity shortens the enzyme half-life. Encapsulation of ASNase in liposomes, nanostructures formed by the self-aggregation of phospholipids, is an attractive alternative to protect the enzyme from plasma proteases and enhance pharmacokinetics profile. In addition, PEGylation might prolong the in vivo circulation of liposomes owing to the spherical shielding conferred by the polyethylene (PEG) corona around the nanostructures. In this paper, ASNase was encapsulated in liposomal formulations composed by 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) containing or not different concentrations of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N [methoxy (polyethylene glycol)-2000] (DSPE-PEG). Nanostructures of approximately 142-202 nm of diameter and polydispersity index (PDI) of 0.069 to 0.190 were obtained and the vesicular shape confirmed by Transmission Electron Microscopy (TEM and cryo-TEM). The encapsulation efficiency (%EE) varied from 10% to 16%. All formulations presented activity in contact with ASNase substrate, indicating the liposomes permeability to Asn and/or enzyme adsorption at the nanostructures' surface; the highest activity was observed for DMPC/DSPE-PEG 10%. Finally, we investigated the activity against the Molt 4 leukemic cell line and found a lower IC50 for the DMPC/DSPE-PEG 10% formulation in comparison to the free enzyme, indicating our system could provide in vivo activity while protecting the enzyme from immune system recognition and proteases degradation.
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Affiliation(s)
- Marina de Souza Guimarães
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
| | - Jorge Javier Muso Cachumba
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
| | - Cecilia Zorzi Bueno
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
| | - Karin Mariana Torres-Obreque
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
| | - Grace Verónica Ruiz Lara
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
| | - Gisele Monteiro
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
| | - Leandro Ramos Souza Barbosa
- Department of General Physics, Institute of Physics, University of São Paulo, São Paulo 05508-000, SP, Brazil
- Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas 13083-100, SP, Brazil
| | - Adalberto Pessoa
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
| | - Carlota de Oliveira Rangel-Yagui
- Department of Biochemical and Pharmaceutical Technology, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil
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Perez N, Altube MJ, Barbosa LRS, Romero EL, Perez AP. Thymus vulgaris essential oil + tobramycin within nanostructured archaeolipid carriers: A new approach against Pseudomonas aeruginosa biofilms. Phytomedicine 2022; 102:154179. [PMID: 35671606 DOI: 10.1016/j.phymed.2022.154179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 02/13/2022] [Revised: 04/20/2022] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Pseudomonas aeruginosa biofilms in the respiratory tract of patients with an excessive inflammatory context are difficult to eradicate. New medicines that simultaneously target biofilms and inflammation should be developed. HYPOTHESIS Co-delivery of Thymus vulgaris essential oil (EOT) and tobramycin (TB) by nanostructured archaeolipids carriers (NAC) could support nebulization as well as improve EOT and TB antioxidant, anti-inflammatory and antibiofilm activity. METHODS NAC(EOT+TB) were prepared by loading EOT and TB in NAC having a compritol and miglyol core, covered with a shell of archaeolipids, extracted from the hyperhalophylic archaebacteria Halorubrum tebenquichense, and Tween 80. NAC(EOT+TB) were structurally characterized, including DSC thermograms, Raman spectra, TB release profile, EOT volatilization and in vitro antioxidant activity. In addition, stability upon nebulization, autoclaving and storage were assessed. The antibiofilm activity on P. aeruginosa PAO1 established biofilm of NAC(EOT+TB) and the cytotoxicity on human lung epithelial cells and macrophage were determined, as well as intracellular reactive oxygen species (ROS) production and cytokines release on LPS stimulated cells. RESULTS NAC(EOT+TB) showed a size of 197 ± 16 nm with PdI of 0.3 ± 0.1 and ζ Potential of -38 ± 3 mV. Structural characterization suggested that EOT was trapped in the compritol-miglyol core and TB was distributed between the surface of nanoparticles and free in solution. NAC(EOT+TB) displayed a dual release profile of TB, a delayed release of EOT and improved EOTs in vitro antioxidant activity. While NAC(EOT+TB) preserved its structural features after nebulization, autoclaving and 18 months of storage, carriers without archaeolipids gelled at room temperature and showed a significant increase of size after the same storage time. Below cytotoxic concentration, NAC(EOT+TB) decreased bacteria viability and enhanced the disruption of established PAO1 biofilms compared to free TB and EOT. Also, the strong entrapment of EOT in NAC(EOT+TB) delayed its volatilization, decreased intracellular ROS production and maintained its anti-inflammatory activity in LPS stimulated cells. CONCLUSION Combination of EOT + TB within NAC(EOT+TB) result in a stable and nebulizable formulation that enhanced the antioxidant and anti-biofilm activity of free ingredients, improved their ability to decrease intracellular ROS and provided anti-inflammatory activity, at non-cytotoxic concentrations on eukaryotic cells.
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Affiliation(s)
- Noelia Perez
- Nanomedicine Research and Development Centre, Science and Technology Department, National University of Quilmes, Roque Saenz Peña 352, Bernal, B1876, Buenos Aires, Argentina
| | - María Julia Altube
- Nanomedicine Research and Development Centre, Science and Technology Department, National University of Quilmes, Roque Saenz Peña 352, Bernal, B1876, Buenos Aires, Argentina
| | - Leandro Ramos Souza Barbosa
- Institute of Physics, University of São Paulo (USP), São Paulo, Brazil; Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
| | - Eder Lilia Romero
- Nanomedicine Research and Development Centre, Science and Technology Department, National University of Quilmes, Roque Saenz Peña 352, Bernal, B1876, Buenos Aires, Argentina
| | - Ana Paula Perez
- Nanomedicine Research and Development Centre, Science and Technology Department, National University of Quilmes, Roque Saenz Peña 352, Bernal, B1876, Buenos Aires, Argentina.
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Silva NSM, Rodrigues LFDC, Dores-Silva PR, Montanari CA, Ramos CHI, Barbosa LRS, Borges JC. Structural, thermodynamic and functional studies of human 71 kDa heat shock cognate protein (HSPA8/hHsc70). Biochim Biophys Acta Proteins Proteom 2021; 1869:140719. [PMID: 34571256 DOI: 10.1016/j.bbapap.2021.140719] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 08/29/2021] [Accepted: 09/21/2021] [Indexed: 01/14/2023]
Abstract
Human 71 kDa heat shock cognate protein (HSPA8, also known as Hsc70, Hsp70-8, Hsc71, Hsp71 or Hsp73) is a constitutively expressed chaperone that is critical for cell proteostasis. In the cytosol, HSPA8 plays a pivotal role in folding and refolding, facilitates protein trafficking across membranes and targets proteins for degradation, among other functions. Here, we report an in solution study of recombinant HSPA8 (rHSPA8) using a variety of biophysical and biochemical approaches. rHSPA8 shares several structural and functional similarities with others human Hsp70s. It has two domains with different stabilities and interacts with adenosine nucleotides with dissociation constants in the low micromolar range, which were higher in the presence of Mg2+. rHSPA8 showed lower ATPase activity than its homolog HSPA5/hGrp78/hBiP, but it was 4-fold greater than that of recombinant HSPA1A/hHsp70-1A, with which it is 86% identical. Small angle X-ray scattering indicated that rHSPA8 behaved as an elongated monomeric protein in solution with dimensions similar to those observed for HSPA1A. In addition, rHSPA8 showed structural flexibility between its compacted and extended conformations. The data also indicated that HSPA8 has capacity in preventing the aggregation of model client proteins. The present study expands the understanding of the structure and activity of this chaperone and aligns with the idea that human homologous Hsp70s have divergent functions.
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Affiliation(s)
| | | | - Paulo Roberto Dores-Silva
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil; Division of Trauma, Critical Care, Burns and Acute Care Surgery, Department of Surgery School of Medicine, University of California San Diego, La Jolla, CA 92093, USA
| | | | | | - Leandro Ramos Souza Barbosa
- Institute of Physics, University of São Paulo, São Paulo, SP, Brazil; Brazilian Synchrotron Light Laboratory (LNLS), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, Brazil
| | - Júlio César Borges
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, Brazil.
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Carducci F, Casadei BR, Mariani P, Barbosa LRS. X-Ray Characterization of Pharmaceutical and Cosmetic Lipidic Nanoparticles for Cutaneous Application. Curr Pharm Des 2019; 25:2364-2374. [PMID: 31584368 DOI: 10.2174/1381612825666190709210211] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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: 04/29/2019] [Accepted: 06/21/2019] [Indexed: 12/12/2022]
Abstract
Starting from the second half of the 1900s, the advent of nanotechnology in medicine has provoked a profound revolution in this area; at present, nanomedicine delivered a remarkably large set of research and clinically useful tools as diagnostic devices, contrast agents, analytical tools, physical therapy applications, and drugdelivery vehicles. Concerning nanoformulations for drug delivery, they are constituted by nanoparticles with dimensions lower than 1 μm, usually characterized by improved pharmacokinetics, taking advantage of specific targeting, and reduced side effects. The contributors to the present chapter are reviewing a range of papers related to the structural characterization of nanoformulations by X-ray diffraction techniques. The whole of the considered papers underlines the essential role that biophysical techniques have acquired as an essential prerequisite to understanding stability, bioavailability, and lipid, biopolymer, and drug organization in nanoformulations.
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Affiliation(s)
- Federica Carducci
- Dipartimento di Scienze della Vita e dell'Ambiente, Universita Politecnica delle Marche, Ancona, Italy
| | - Bruna Renata Casadei
- Departamento de Fisica Geral, Instituto de Fisica, Universidade de São Paulo, Sao Paulo, Brazil
| | - Paolo Mariani
- Dipartimento di Scienze della Vita e dell'Ambiente, Universita Politecnica delle Marche, Ancona, Italy
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Pachioni-Vasconcelos JDA, Lopes AM, Apolinário AC, Valenzuela-Oses JK, Costa JSR, Nascimento LDO, Pessoa A, Barbosa LRS, Rangel-Yagui CDO. Nanostructures for protein drug delivery. Biomater Sci 2016; 4:205-18. [DOI: 10.1039/c5bm00360a] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Nanostructured systems, such as nanoemulsions and polymersomes, are important tools to develop safe and effective therapeutic protein preparations.
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Affiliation(s)
| | - André Moreni Lopes
- Department of Biochemical and Pharmaceutical Technology
- School of Pharmaceutical Sciences
- University of São Paulo
- Brazil
| | | | | | | | - Laura de Oliveira Nascimento
- Department of Biochemistry and Tissue Biology
- Institute of Biology
- University of Campinas
- Brazil
- Faculty of Pharmaceutical Sciences
| | - Adalberto Pessoa
- Department of Biochemical and Pharmaceutical Technology
- School of Pharmaceutical Sciences
- University of São Paulo
- Brazil
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Dores-Silva PR, Beloti LL, Minari K, Silva SMO, Barbosa LRS, Borges JC. Structural and functional studies of Hsp70-escort protein--Hep1--of Leishmania braziliensis. Int J Biol Macromol 2015; 79:903-12. [PMID: 26071939 DOI: 10.1016/j.ijbiomac.2015.05.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [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: 03/18/2015] [Revised: 05/22/2015] [Accepted: 05/23/2015] [Indexed: 12/14/2022]
Abstract
Hep1 is a mitochondrial Hsp70 (mtHsp70) co-chaperone that presents a zinc finger domain essential for its function. This co-chaperone acts to maintain mtHsp70 in its soluble and functional state. In this work, we have demonstrated that Leishmania braziliensis mtHsp70 (LbmtHsp70) is also dependent on the assistance of Hep1. To understand the L. braziliensis Hep1 (LbHep1) structure-function relationship, we produced LbHep1 and two truncated mutants corresponding to the C-terminal zinc finger domain and the N-terminal region. We observed that LbHep1 is composed of an unfolded N-terminal region and a β-sheet-folded C-terminal domain, which holds the zinc-binding motif. Both LbHep1 and the zinc finger domain construction maintained LbmtHsp70 solubility in co-expression systems after cell lysis. In solution, LbHep1 behaved as a highly elongated monomer, probably due to the unfolded N-terminal region. Furthermore, we also observed that the zinc ion interacted with LbHep1 with high affinity and was critical for LbHep1 structure and stability because its removal from LbHep1 solutions altered the protein structure and stability. In vitro, LbHep1 protected, in sub-stoichiometric fashion, LbmtHsp70 from thermally induced aggregation but did not present intrinsic chaperone activity on model client proteins. Therefore, LbHep1 is a specific chaperone for LbmtHsp70.
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Affiliation(s)
- P R Dores-Silva
- Institute of Chemistry of São Carlos, University of São Paulo - USP, São Carlos, SP 13560-970, Brazil
| | - L L Beloti
- Institute of Chemistry of São Carlos, University of São Paulo - USP, São Carlos, SP 13560-970, Brazil
| | - K Minari
- Institute of Chemistry of São Carlos, University of São Paulo - USP, São Carlos, SP 13560-970, Brazil; Post-Graduation Program in Evolutionary Genetics and Molecular Biology, Federal University of São Carlos - UFSCar, São Carlos, SP 13565-905, Brazil
| | - S M O Silva
- Institute of Chemistry of São Carlos, University of São Paulo - USP, São Carlos, SP 13560-970, Brazil
| | - L R S Barbosa
- Institute of Physics, University of São Paulo - USP, São Paulo, SP 05508-090, Brazil
| | - J C Borges
- Institute of Chemistry of São Carlos, University of São Paulo - USP, São Carlos, SP 13560-970, Brazil.
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Santana H, Avila CL, Cabrera I, Páez R, Falcón V, Pessoa A, Ventosa N, Veciana J, Itri R, Barbosa LRS. How does growth hormone releasing hexapeptide self-assemble in nanotubes? Soft Matter 2014; 10:9260-9269. [PMID: 25325399 DOI: 10.1039/c4sm01693a] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Growth hormone releasing peptide, GHRP-6, a hexapeptide (His-(D-Trp)-Ala-Trp-(D-Phe)-Lys-NH2, MW = 872.44 Da) that belongs to a class of synthetic growth hormone secretagogues, can stimulate growth hormone secretion from somatotrophs in several species including humans. In the present study, we demonstrate that GHRP-6 dispersed in aqueous solution, at pH 7.0, room temperature of 22 °C, is able to form long nanotubes, which is evidenced by combining small angle X-ray scattering (SAXS), transmission electron microscopy and molecular dynamics simulation results. Such nanotubes possess inner and outer cross-sections equal to 6.7(2) nm and 13.4(5) nm, respectively. The mechanism of peptide self-assembly was determined by molecular dynamics simulations revealing that the peptides self-assemble like amphiphilic molecules in aqueous solution in a partially interdigitated structure. In this case, the position of the positively charged amino terminus is located at the peptide-water interface, whereas the neutral NH2-capped carboxy terminus remains buried at the hydrophobic core. In contrast, the long side chain of Lys-6 stretches out of the hydrophobic core positioning its positive charge near the cylinder surface. The peptide configuration in the nanotube wall comes from the interplay between the hydrophobic interactions of the aromatic side chains of GHRP-6 and the electrostatic repulsion of its cationic charges. On increasing the peptide concentration, the long nanotubes self-arrange in solution displaying a bi-dimensional hexagonal-like packing in the SAXS curves, with a center-to-center distance of ∼15 nm. Further, we also show that the nanostructure formed in solution is quite stable and is preserved following transfer to a solid support.
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Affiliation(s)
- Héctor Santana
- Department of Pharmaceutical Technology, Center for Genetic Engineering and Biotechnology, Ave 31/158 and 190, PO Box. 6162, Havana 10600, Cuba
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Percebom AM, Barbosa LRS, Itri R, Loh W. How does the ethoxylated grafting of polyelectrolytes affect the self-assembly of polyanion-cationic surfactant complex salts? Langmuir 2014; 30:11493-11503. [PMID: 25207859 DOI: 10.1021/la5019604] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A cationic surfactant and different anionic copolymers randomly grafted with side chains of ethylene oxide were used to prepare stoichiometric complex salts. Variations in the length or proportion of side chains were shown to be responsible for affecting the surfactant phase behavior in water, resulting in the observation of a number of structures characterized by small angle X-ray scattering measurements, including a hierarchical micellar system and different liquid-crystalline phases. Additionally, although aqueous mixtures of stoichiometric complex salts usually phase separate, the presence of a sufficiently high weight fraction of ethylene oxide side chains can enhance the solubility of the complex salt aggregates in water over a wide range of concentration. Moreover, a dispersion of an isotropic concentrated solution of complex salts is formed at higher temperatures in a reversible process. In summary, this study proves the importance of the polyion structure for tuning the properties of systems of complex salts.
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Affiliation(s)
- Ana Maria Percebom
- Institute of Chemistry, University of Campinas (UNICAMP) , CP 6154 Campinas, SP Brazil
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Dores-Silva PR, Minari K, Ramos CHI, Barbosa LRS, Borges JC. Structural and stability studies of the human mtHsp70-escort protein 1: an essential mortalin co-chaperone. Int J Biol Macromol 2013; 56:140-8. [PMID: 23462535 DOI: 10.1016/j.ijbiomac.2013.02.009] [Citation(s) in RCA: 21] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 02/07/2013] [Accepted: 02/09/2013] [Indexed: 11/20/2022]
Abstract
Mitochondrial Hsp70 is involved in both protein import and folding process, among other essential functions. In mammalian cells, due to its role in the malignant process, it receives the name of mortalin. Despite its importance in protein and mitochondrial homeostasis, mortalin tends to self-aggregate in vitro and in vivo, the later leads to mitochondrial biogenesis failure. Recently, a zinc-finger protein, named Hsp70-escort protein 1 (Hep1, also called Zim17/TIM15/DNLZ), was described as an essential human mitochondrial mortalin co-chaperone which avoids its self-aggregation. Here, we report structural studies of the human Hep1 (hHep1). The results indicate that hHep1 shares some structural similarities with the yeast ortholog despite the low identity and functional differences. We also observed that hHep1 oligomerizes in a concentration-dependent fashion and that the zinc ion, which is essential for hHep1 in vivo function, has an important protein-structure stabilizing effect.
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Affiliation(s)
- P R Dores-Silva
- Instituto de Química de São Carlos, Universidade de São Paulo - USP, São Carlos, SP 13560-970, Brazil
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Bueno VB, Silva AM, Barbosa LRS, Catalani LH, Teixeira-Neto É, Cornejo DR, Petri DFS. Hybrid composites of xanthan and magnetic nanoparticles for cellular uptake. Chem Commun (Camb) 2013; 49:9911-3. [DOI: 10.1039/c3cc42277a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Campana PT, Barbosa LRS, Itri R. Conformational stability of peanut agglutinin using small angle X-ray scattering. Int J Biol Macromol 2011; 48:398-402. [DOI: 10.1016/j.ijbiomac.2010.12.009] [Citation(s) in RCA: 6] [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: 09/29/2010] [Revised: 12/07/2010] [Accepted: 12/09/2010] [Indexed: 11/29/2022]
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Barbosa LRS, Rigos CF, Yoneda JS, Itri R, Ciancaglini P. Unraveling the Na,K-ATPase alpha(4) subunit assembling induced by large amounts of C(12)E(8) by means of small-angle X-ray scattering. J Phys Chem B 2010; 114:11371-6. [PMID: 20715782 DOI: 10.1021/jp1013829] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In the current work, we studied the effect of the nonionic detergent dodecyloctaethyleneglycol, C(12)E(8), on the structure and oligomeric form of the Na,K-ATPase membrane enzyme (sodium-potassium pump) in aqueous suspension, by means of small-angle X-ray scattering (SAXS). Samples composed of 2 mg/mL of Na,K-ATPase, extracted from rabbit kidney medulla, in the presence of a small amount of C(12)E(8) (0.005 mg/mL) and in larger concentrations ranging from 2.7 to 27 mg/mL did not present catalytic activity. Under this condition, an oligomerization of the alpha subunits is expected. SAXS data were analyzed by means of a global fitting procedure supposing that the scattering is due to two independent contributions: one coming from the enzyme and the other one from C(12)E(8) micelles. In the small detergent content (0.005 mg/mL), the SAXS results evidenced that Na,K-ATPase is associated into aggregates larger than (alphabeta)(2) form. When 2.7 mg/mL of C(12)E(8) is added, the data analysis revealed the presence of alpha(4) aggregates in the solution and some free micelles. Increasing the detergent amount up to 27 mg/mL does not disturb the alpha(4) aggregate: just more micelles of the same size and shape are proportionally formed in solution. We believe that our results shed light on a better understanding of how nonionic detergents induce subunit dissociation and reassembling to minimize the exposure of hydrophobic residues to the aqueous solvent.
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