1
|
Rossi LG, Andrade MEB, Rabelo CHS, Siqueira GR, Vicente EF, Silva WL, Silva MM, Reis RA. Flint corn silage management: influence of maturity stage, inoculation with Lentilactobacillus buchneri, and storage time on fermentation pattern, aerobic stability, and nutritional characteristics. Front Microbiol 2023; 14:1223717. [PMID: 37533825 PMCID: PMC10390726 DOI: 10.3389/fmicb.2023.1223717] [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: 05/16/2023] [Accepted: 07/05/2023] [Indexed: 08/04/2023] Open
Abstract
Introduction High quality corn silage depends on factors such as corn type, stage of crop development at harvest time, fermentation time, in addition to use or not of inoculants. This study aimed to investigate the impact of maturity stage, bacterial inoculation, and storage time on fermentation, aerobic stability, and nutritional characteristics of flint corn silage and their implications for corn silage management. Methods A flint corn hybrid was harvested very early, early, and medium (at 250, 300 and 350 g dry matter (DM)/kg as fed, respectively) and ensiled in mini-silos without (control) or with Lentilactobacillus buchneri CNCM I-4323 at 1 × 105 cfu/g for 120, 240 and 360 d to investigate how these factors interact with each other. Results and discussion There was only a small increase (7 g/kg starch; p = 0.003) in starch digestibility (starch-D) in the silages stored for 360 d when compared to that stored for 240 d, but with no difference for 120 d. Despite the reduced starch-D (526 vs. 694 g/kg starch; p < 0.001), silages produced from medium harvest had higher (p < 0.001) starch content (317 vs. 137 g/kg DM) and higher amount of digestible starch (169 vs. 98.5 g/kg DM; p < 0.001) compared to very early harvest. The 2-way interactions (inoculation × storage time and maturity × storage time) showed that inoculation of corn silage with L. buchneri increased (p < 0.001) the aerobic stability, and that more mature crop silage had higher aerobic stability (140 h; p = 0.036) than the others (118 and 48.5 h for those silages from very early and early harvest). Conclusion The storage for a longer time (>120 d) with the goal of increasing silage digestibility did not occur. Harvesting whole-crop flint corn with 300 to 350 g/kg DM is desirable to have higher DM yield and starch accumulation. Inoculation with L. buchneri is recommended to preserve the silage against aerobic deterioration. This study has shown the importance of harvesting flint corn at the right time, and the need for inoculation with L. buchneri to ensure greater yield, starch accumulation, and silage preservation, if 120 days of storage are not exceeded.
Collapse
Affiliation(s)
- Luis G. Rossi
- Department of Animal Science, São Paulo State University, Jaboticabal, SP, Brazil
| | - Marina E. B. Andrade
- Department of Animal Science, São Paulo State University, Jaboticabal, SP, Brazil
| | - Carlos H. S. Rabelo
- Department of Plant Science, Federal University of Pelotas, Capão do Leão, RS, Brazil
| | - Gustavo R. Siqueira
- Department of Animal Science, São Paulo State University, Jaboticabal, SP, Brazil
- São Paulo State Agency for Agribusiness Technology Alta Mogiana, Colina, SP, Brazil
| | - Eduardo F. Vicente
- Faculty of Science and Engineering, São Paulo State University, Tupã, SP, Brazil
| | - Wilton L. Silva
- Department of Animal Science, Federal University of Goiás, Goiânia, GO, Brazil
| | - Matheus M. Silva
- Department of Animal Science, São Paulo State University, Jaboticabal, SP, Brazil
| | - Ricardo A. Reis
- Department of Animal Science, São Paulo State University, Jaboticabal, SP, Brazil
| |
Collapse
|
2
|
Silveira RF, Roque-Borda CA, Vicente EF. Antimicrobial peptides as a feed additive alternative to animal production, food safety and public health implications: An overview. Anim Nutr 2021; 7:896-904. [PMID: 34632120 PMCID: PMC8484980 DOI: 10.1016/j.aninu.2021.01.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 12/21/2020] [Accepted: 01/28/2021] [Indexed: 02/07/2023]
Abstract
In the last few years, feed additives have been used in animal nutrition to improve nutrient utilization, health parameters and animal performance. However, the use of antibiotics as feed additives has allowed the occurrence of antimicrobial resistance (AMR), which can bring as a consequence, an increase in the morbidity and mortality of diseases that were previously treatable with antibiotics. In this context, antimicrobial peptides (AMP) have appeared as a promising strategy because they have multiple biological activities and represent a powerful strategy to prevent the development of resistant microorganisms. Despite the small number of studies applied in vivo, AMP appear as a potent alternative to the use of antibiotics in animal nutrition, due to an increase in feed efficiency and the prevention/treatment of some animal diseases. This review discusses the problems associated with antimicrobial resistance and the use of AMP as a strong candidate to replace conventional antibiotics, mainly in the animal industry.
Collapse
Affiliation(s)
- Raiza F Silveira
- São Paulo State University, School of Agricultural and Veterinarian Sciences, Jaboticabal, São Paulo, Brazil
| | - Cesar A Roque-Borda
- São Paulo State University, School of Agricultural and Veterinarian Sciences, Jaboticabal, São Paulo, Brazil
| | - Eduardo F Vicente
- São Paulo State University, School of Sciences and Engineering, Tupã, São Paulo, Brazil
| |
Collapse
|
3
|
Amorim CA, Blanco KC, Costa IM, Vicente EF, da S Petruci JF, Contiero J, Leite ER, Chiquito AJ. Active-electrode biosensor of SnO 2 nanowire for cyclodextrin detection from microbial enzyme. Nanotechnology 2020; 31:165501. [PMID: 31770731 DOI: 10.1088/1361-6528/ab5bd7] [Citation(s) in RCA: 3] [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] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Cyclodextrin (CD) is a conical compound used in food and pharmaceutical industry to complexation of hydrophobic substances. It is a product of microbial enzymes which converts starch into CD during their activity. We aim to detect CD using active-electrode biosensor of SnO2. They were grown on active electrode by the VLS method. The CD consists of several glucose units which have hydroxyl groups which tend to bind to interface states present in nanowires changing their conductivity. Experimental results of electrical conductivity at different CD concentrations are presented. A model that describes the influence of adsorbed glucose on nanowires and its electrical properties is also presented. Some general observations are performed on the applicability of the CD adsorption method by the nanowire-based biosensor.
Collapse
Affiliation(s)
- Cleber A Amorim
- Universidade Estadual Paulista, Faculdade de Ciências e Engenharia de Tupã, Tupã, Av. Domingos da Costa Lopes, 780 Jardim Itaipu, Tupã, SP, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
4
|
Carretero GPB, Vicente EF, Cilli EM, Alvarez CM, Jenssen H, Schreier S. Dissecting the mechanism of action of actinoporins. Role of the N-terminal amphipathic α-helix in membrane binding and pore activity of sticholysins I and II. PLoS One 2018; 13:e0202981. [PMID: 30161192 PMCID: PMC6117003 DOI: 10.1371/journal.pone.0202981] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 08/13/2018] [Indexed: 11/19/2022] Open
Abstract
Actinoporins sticholysin I and sticholysin II (St I, St II) are proposed to lyse model and biomembranes via toroidal pore formation by their N-terminal domain. Based on the hypothesis that peptide fragments can reproduce the structure and function of this domain, the behavior of peptides containing St I residues 12–31 (StI12-31), St II residues 11–30 (StII11-30), and its TOAC-labeled analogue (N-TOAC-StII11-30) was examined. Molecular modeling showed a good match with experimental structures, indicating amphipathic α-helices in the same regions as in the toxins. CD spectra revealed that the peptides were essentially unstructured in aqueous solution, acquiring α-helical conformation upon interaction with micelles and large unilamellar vesicles (LUV) of variable lipid composition. Fluorescence quenching studies with NBD-containing lipids indicated that N-TOAC-StII11-30’s nitroxide moiety is located in the membranes polar head group region. Pyrene-labeled phospholipid inter-leaflet redistribution suggested that the peptides form toroidal pores, according to the mechanism of action proposed for the toxins. Binding occurred only to negatively charged LUV, indicating the importance of electrostatic interactions; in contrast the peptides bound to both negatively charged and zwitterionic micelles, pointing to a lesser influence of these interactions. In addition, differences between bilayers and micelles in head group packing and in curvature led to differences in peptide-membrane interaction. We propose that the peptides topography in micelles resembles that of the toxins in the toroidal pore. The peptides mimicked the toxins permeabilizing activity, St II peptides being more effective than StI12-31. To our knowledge, this is the first demonstration that differences in the toxins N-terminal amphipathic α-helix play a role in the difference between St I and St II activities.
Collapse
Affiliation(s)
- Gustavo P. B. Carretero
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
| | - Eduardo F. Vicente
- Faculty of Science and Engineering, State University of São Paulo, Tupã, Brazil
| | - Eduardo M. Cilli
- Institute of Chemistry, State University of São Paulo, Araraquara, Brazil
| | | | - Håvard Jenssen
- Department of Science and Environment, Roskilde University, Roskilde, Denmark
| | - Shirley Schreier
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
- * E-mail:
| |
Collapse
|
5
|
Vicente EF, Sahu ID, Crusca E, Basso LGM, Munte CE, Costa-Filho AJ, Lorigan GA, Cilli EM. HsDHODH Microdomain-Membrane Interactions Influenced by the Lipid Composition. J Phys Chem B 2017; 121:11085-11095. [PMID: 29148803 DOI: 10.1021/acs.jpcb.7b09642] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Human dihydroorotate dehydrogenase (HsDHODH) enzyme has been studied as selective target for inhibitors to block the enzyme activity, intending to prevent proliferative diseases. The N-terminal microdomain seems to play an important role in the enzyme function. However, the molecular mechanism of action and dynamics of this region are not totally understood yet. This study analyzes the interaction and conformation in model membranes of HsDHODH microdomain using peptide analogues containing the paramagnetic amino acid TOAC at strategic positions. In buffer solution, the analogues presented a disordered conformation, but acquired a high content of α-helical structure in membrane mimetics, which was found to be lipid dependent. The microdomain peptide structure in micelles showed a very different peptide conformation when compared to the reported crystal structure, displaying a conformational flexibility of its helices, promoted by the connecting loop, which might be functionally relevant. Electron spin resonance in membrane compositions containing POPC, POPE, and cardiolipin showed that interaction of the analogues was enhanced by the presence of cardiolipin, indicating that the microdomain preferentially interacts with cardiolipin-containing membranes. Therefore, the great flexibility of the microdomain and the cardiolipin affinity should be considered in further studies aimed at finding new inhibitory compounds to fight proliferative diseases.
Collapse
Affiliation(s)
- Eduardo F Vicente
- School of Science and Engineering, São Paulo State University (UNESP) , 17602-496, Tupã, SP Brazil
| | - Indra D Sahu
- Department of Chemistry and Biochemistry, Miami University , Oxford, Ohio 45056, United States
| | - Edson Crusca
- Institute of Chemistry, São Paulo State University (UNESP) , 14800-900, Araraquara, SP Brazil.,Instituto de Física de São Carlos, Universidade de São Paulo (USP) , 13566-590 - São Carlos, SP Brazil
| | - Luis G M Basso
- Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo (USP) , 14040-901, Ribeirão Preto, SP Brazil
| | - Claudia E Munte
- Instituto de Física de São Carlos, Universidade de São Paulo (USP) , 13566-590 - São Carlos, SP Brazil
| | - Antonio J Costa-Filho
- Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo (USP) , 14040-901, Ribeirão Preto, SP Brazil
| | - Gary A Lorigan
- Department of Chemistry and Biochemistry, Miami University , Oxford, Ohio 45056, United States
| | - Eduardo M Cilli
- Institute of Chemistry, São Paulo State University (UNESP) , 14800-900, Araraquara, SP Brazil
| |
Collapse
|
6
|
Lana JFSD, Weglein A, Sampson SE, Vicente EF, Huber SC, Souza CV, Ambach MA, Vincent H, Urban-Paffaro A, Onodera CMK, Annichino-Bizzacchi JM, Santana MHA, Belangero WD. Randomized controlled trial comparing hyaluronic acid, platelet-rich plasma and the combination of both in the treatment of mild and moderate osteoarthritis of the knee. J Stem Cells Regen Med 2016. [PMID: 28096631 PMCID: PMC5227106 DOI: 10.46582/jsrm.1202011] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Objective: This study aims at evaluating the clinical effects of Platelet Rich Plasma (PRP) and Hyaluronic Acid (HA) as individual treatments for mild to moderate Osteoarthritis (OA) and it also examines the potential synergistic effects of PRP in combination with HA. Research continues to emerge examining the potential therapeutic efficacy of HA and PRP as autologous injectable treatments for joint arthritis. However, there is a paucity of research investigating the effects of combining HA and PRP on pain and functional status in patients with OA. Design: In this multi-center, randomized, controlled, double blind, prospective trial, 105 patients with mild to moderate knee osteoarthritis, who met the study criteria, were randomly allocated to one of three interventions: HA (n=36), PRP (n=36), or HA+PRP (n=33). Each patient received 3 intra-articular knee injections of their assigned substance, with 2 week intervals between each injection. Clinical outcomes were evaluated using the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and Visual Analogue Scale (VAS) questionnaire at baseline and after 1,3,6 and 12 months. Results: The study showed that the PRP group have significant reduction in VAS scores at 1 (p= 0.003), 3 (p= 0.0001), 6 (p= 0.0001) and 12 (p= 0.000) months when compared to HA. In addition, the PRP group illustrated greater improvement in WOMAC physical activity scale at 12 months (p= 0.008) when compared to the HA group. Combining HA and PRP resulted in a significant decreases in pain (p=0.0001) and functional limitation (p=0.0001) when compared to HA alone at 1 year post treatment; and significantly increased physical function at 1 (p=0.0004) and 3 (p=.011) months when compared to PRP alone. Conclusion: The findings of the study support the use of autologous PRP as an effective treatment of mild to moderate knee osteoarthritis. It also shows that the combination of HA and PRP resulted to better outcomes than HA alone up to 1 year and PRP alone up to 3 months. Furthermore, the results suggest that combination of PRP and HA could potentially provide better functional outcomes in the first 30 days after treatment with both PRP and HA alone.
Collapse
Affiliation(s)
- José F S D Lana
- Bone and Cartilage Institute - (IOC) Indaiatuba - Brazil; Institute of Orthopedics and Traumatology of University of Campinas (UNICAMP) - Brazil
| | | | | | | | - Stephany Cares Huber
- Bone and Cartilage Institute - (IOC) Indaiatuba - Brazil; Hemocentro of Campinas, University of Campinas (UNICAMP)- Brazil
| | - Clarissa V Souza
- Institute of Orthopedics and Traumatology of University of Campinas (UNICAMP) - Brazil
| | | | - Hunter Vincent
- Department of Physical Medicine and Rehabilitation: UC Davis
| | | | | | | | | | - William D Belangero
- Institute of Orthopedics and Traumatology of University of Campinas (UNICAMP) - Brazil
| |
Collapse
|
7
|
Basso LGM, Vicente EF, Crusca E, Cilli EM, Costa-Filho AJ. SARS-CoV fusion peptides induce membrane surface ordering and curvature. Sci Rep 2016; 6:37131. [PMID: 27892522 PMCID: PMC5125003 DOI: 10.1038/srep37131] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [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: 05/28/2016] [Accepted: 10/24/2016] [Indexed: 12/23/2022] Open
Abstract
Viral membrane fusion is an orchestrated process triggered by membrane-anchored viral fusion glycoproteins. The S2 subunit of the spike glycoprotein from severe acute respiratory syndrome (SARS) coronavirus (CoV) contains internal domains called fusion peptides (FP) that play essential roles in virus entry. Although membrane fusion has been broadly studied, there are still major gaps in the molecular details of lipid rearrangements in the bilayer during fusion peptide-membrane interactions. Here we employed differential scanning calorimetry (DSC) and electron spin resonance (ESR) to gather information on the membrane fusion mechanism promoted by two putative SARS FPs. DSC data showed the peptides strongly perturb the structural integrity of anionic vesicles and support the hypothesis that the peptides generate opposing curvature stresses on phosphatidylethanolamine membranes. ESR showed that both FPs increase lipid packing and head group ordering as well as reduce the intramembrane water content for anionic membranes. Therefore, bending moment in the bilayer could be generated, promoting negative curvature. The significance of the ordering effect, membrane dehydration, changes in the curvature properties and the possible role of negatively charged phospholipids in helping to overcome the high kinetic barrier involved in the different stages of the SARS-CoV-mediated membrane fusion are discussed.
Collapse
Affiliation(s)
- Luis G M Basso
- Grupo de Biofísica Molecular Sérgio Mascarenhas, Instituto de Física de São Carlos, Universidade de São Paulo, Avenida Trabalhador São-carlense, 400, Centro, São Carlos, SP, Brazil.,Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Av. Bandeirantes, 3900, 14040-901, Ribeirão Preto, SP, Brazil
| | - Eduardo F Vicente
- Faculdade de Ciências e Engenharia, UNESP - Univ Estadual Paulista, Campus de Tupã. Rua Domingos da Costa Lopes, 780, 17602-496, Tupã, SP, Brazil
| | - Edson Crusca
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP - Univ Estadual Paulista. Rua Prof. Franscisco Degni, 55, 14800-900, Araraquara, SP, Brazil
| | - Eduardo M Cilli
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP - Univ Estadual Paulista. Rua Prof. Franscisco Degni, 55, 14800-900, Araraquara, SP, Brazil
| | - Antonio J Costa-Filho
- Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo. Av. Bandeirantes, 3900, 14040-901, Ribeirão Preto, SP, Brazil
| |
Collapse
|
8
|
Vicente EF, Sahu ID, Costa-Filho AJ, Cilli EM, Lorigan GA. Conformational changes of the HsDHODH N-terminal Microdomain via DEER Spectroscopy. J Phys Chem B 2015; 119:8693-7. [PMID: 26086954 DOI: 10.1021/acs.jpcb.5b01706] [Citation(s) in RCA: 17] [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: 01/06/2023]
Abstract
The human enzyme dihydroorotate dehydrogenase (HsDHODH) has been studied for being a target for development of new antineoplasic and antiproliferative drugs. The synthetic peptide N-t(DH) represents the N-terminal microdomain of this enzyme, responsible for anchoring it to the inner mitochondrial membrane. Also, it is known to harbor quinones that are essential for enzyme catalysis. Here we report structural features of the peptide/membrane interactions obtained by using CD and DEER spectroscopic techniques, both in micelles and in lipid vesicles. The data revealed different peptide conformational states in micelles and liposomes, which could suggest that this microdomain acts in specific regions or areas of the mitochondria, which can be related with the control of the quinone access to the HsDHODH active site. This is the first study to report on conformational changes of the HsDHODH N-terminal microdomain through a combination of CD and DEER spectroscopic techniques.
Collapse
Affiliation(s)
- Eduardo F Vicente
- †UNESP - Univ Estadual Paulista, Campus de Tupã, 17602-496, Tupã, SP Brazil
| | - Indra D Sahu
- ‡Department of Chemistry and Biochemistry, Miami University, 45056, Oxford, Ohio United States
| | - Antonio J Costa-Filho
- §Laboratório de Biofísica Molecular, Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo - USP,14040-901, Ribeirão Preto, SP Brazil
| | - Eduardo M Cilli
- ∥Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP - Univ Estadual Paulista, 14800-900, Araraquara, SP Brazil
| | - Gary A Lorigan
- ‡Department of Chemistry and Biochemistry, Miami University, 45056, Oxford, Ohio United States
| |
Collapse
|
9
|
Vicente EF, Basso LGM, Cespedes GF, Lorenzón EN, Castro MS, Mendes-Giannini MJS, Costa-Filho AJ, Cilli EM. Dynamics and conformational studies of TOAC spin labeled analogues of Ctx(Ile(21))-Ha peptide from Hypsiboas albopunctatus. PLoS One 2013; 8:e60818. [PMID: 23585852 PMCID: PMC3621989 DOI: 10.1371/journal.pone.0060818] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 03/03/2013] [Indexed: 11/26/2022] Open
Abstract
Antimicrobial peptides (AMPs) isolated from several organisms have been receiving much attention due to some specific features that allow them to interact with, bind to, and disrupt cell membranes. The aim of this paper was to study the interactions between a membrane mimetic and the cationic AMP Ctx(Ile(21))-Ha as well as analogues containing the paramagnetic amino acid 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid (TOAC) incorporated at residue positions n = 0, 2, and 13. Circular dichroism studies showed that the peptides, except for [TOAC(13)]Ctx(Ile(21))-Ha, are unstructured in aqueous solution but acquire different amounts of α-helical secondary structure in the presence of trifluorethanol and lysophosphocholine micelles. Fluorescence experiments indicated that all peptides were able to interact with LPC micelles. In addition, Ctx(Ile(21))-Ha and [TOAC(13)]Ctx(Ile(21))-Ha peptides presented similar water accessibility for the Trp residue located near the N-terminal sequence. Electron spin resonance experiments showed two spectral components for [TOAC(0)]Ctx(Ile(21))-Ha, which are most likely due to two membrane-bound peptide conformations. In contrast, TOAC(2) and TOAC(13) derivatives presented a single spectral component corresponding to a strong immobilization of the probe. Thus, our findings allowed the description of the peptide topology in the membrane mimetic, where the N-terminal region is in dynamic equilibrium between an ordered, membrane-bound conformation and a disordered, mobile conformation; position 2 is most likely situated in the lipid polar head group region, and residue 13 is fully inserted into the hydrophobic core of the membrane.
Collapse
Affiliation(s)
- Eduardo F. Vicente
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP-Univ Estadual Paulista, Araraquara/SP, Brazil
| | - Luis Guilherme M. Basso
- Grupo de Biofísica Molecular Sérgio Mascarenhas, Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos/SP, Brazil
| | - Graziely F. Cespedes
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP-Univ Estadual Paulista, Araraquara/SP, Brazil
| | - Esteban N. Lorenzón
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP-Univ Estadual Paulista, Araraquara/SP, Brazil
| | - Mariana S. Castro
- Brazilian Center for Protein Research, Department of Cell Biology, University of Brasília, Brasília/DF, Brazil
| | - Maria José S. Mendes-Giannini
- Departamento de Análises Clínicas, Faculdade de Ciências Farmacêuticas, UNESP-Univ Estadual Paulista, Araraquara/SP, Brazil
| | - Antonio José Costa-Filho
- Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto/SP, Brazil
| | - Eduardo M. Cilli
- Departamento de Bioquímica e Tecnologia Química, Instituto de Química, UNESP-Univ Estadual Paulista, Araraquara/SP, Brazil
| |
Collapse
|
10
|
Cilli EM, Vicente EF, Crusca E, Nakaie CR. EPR investigation of the influence of side chain protecting groups on peptide–resin solvation of the Asx and Glx model containing peptides. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.05.164] [Citation(s) in RCA: 6] [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] [Indexed: 11/30/2022]
|