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Sousa B.L.,Federal University of Ceará | Silva-Filho J.C.,Federal University of Ceará | Kumar P.,University of Graz | Graewert M.A.,German Electron Synchrotron | And 10 more authors.
International Journal of Biochemistry and Cell Biology | Year: 2016

Legume lectins are the most thoroughly studied group of lectins and have been widely linked to many pathological processes. Their use as immunohistochemistry markers for cell profiling and cancer diagnosis have made these molecules important tools for immunological studies and have stimulated the prospection and characterization of new lectins. The crystal structures of a recombinant seed lectin from Vatairea macrocarpa (rVML) and its complexes with GalNAcα1-O-Ser, GalNAc and α-lactose, have been determined at 1.90, 1.97, 2.70 and 1.83 Å resolution, respectively. Small angle X-ray scattering and calorimetry assays have confirmed the same pH stable oligomerization pattern and binding profiles proposed for its wild-type counterpart. In silico analyzes have explored the potential of this recombinant lectin as new tool for cancer research through a comparative profile with other legume lectins widely used for cancer diagnosis and prognosis. The results suggest the recognition of specific epitopes exhibited on different cancer cells as a process that relies on the disposition of hydrophobic clusters and charged regions around the lectin carbohydrate-binding site, favouring the anchorage of different groups in the antigen boundaries, highlighting the different potential of each analyzed lectin. In conclusion, the experimental results and comparative analysis show that rVML is as a promising tool for cancer research, able to bind with high affinity specific tumor-associated antigens, highly stable and easily produced. © 2016 Elsevier Ltd. All rights reserved.


PubMed | German Electron Synchrotron, Federal University of Paraiba, University of Vienna, Federal University of Ceará and 3 more.
Type: | Journal: The international journal of biochemistry & cell biology | Year: 2016

Legume lectins are the most thoroughly studied group of lectins and have been widely linked to many pathological processes. Their use as immunohistochemistry markers for cell profiling and cancer diagnosis have made these molecules important tools for immunological studies and have stimulated the prospection and characterization of new lectins. The crystal structures of a recombinant seed lectin from Vatairea macrocarpa (rVML) and its complexes with GalNAc1-O-Ser, GalNAc and -lactose, have been determined at 1.90, 1.97, 2.70 and 1.83 resolution, respectively. Small angle X-ray scattering and calorimetry assays have confirmed the same pH stable oligomerization pattern and binding profiles proposed for its wild-type counterpart. In silico analyzes have explored the potential of this recombinant lectin as new tool for cancer research through a comparative profile with other legume lectins widely used for cancer diagnosis and prognosis. The results suggest the recognition of specific epitopes exhibited on different cancer cells as a process that relies on the disposition of hydrophobic clusters and charged regions around the lectin carbohydrate-binding site, favouring the anchorage of different groups in the antigen boundaries, highlighting the different potential of each analyzed lectin. In conclusion, the experimental results and comparative analysis show that rVML is as a promising tool for cancer research, able to bind with high affinity specific tumor-associated antigens, highly stable and easily produced.


de Sousa B.L.,Federal University of Ceará | Nagano C.S.,Federal University of Ceará | Simoes R.D.C.,Federal University of Ceará | Simoes R.D.C.,Federal University of Bahia | And 5 more authors.
Biochimie | Year: 2016

Legume lectins have been widely studied and applied for many purposes in the last few decades, but many of their physiological aspects remain elusive. The Diocleinae legume subtribe, which includes intensively explored lectins, such as ConA, presents an unusual and extensive post-translational process which results in minor alterations in protein structure, in turn making its function elusive. Despite previous reports about Diocleinae precursor activity, no structural or functional analyses have ever been carried out to understand the impacts of post-translational processing relative to lectin structure and binding specificity. Here we analyzed the functionality of a non glycosylated, recombinantly expressed lectin precursor from Dioclea grandiflora through inhibition assays, corroborating the experimental data with structural information generated by molecular modeling, docking calculations and molecular dynamics simulations. We demonstrate that Diocleinae precursors are active and share the same carbohydrate specificity as mature lectins. At the same time, however, subtle structural alterations were detected and mostly result in an “incomplete” functionality of the precursor, as consequence of an immature binding site and an unstructured tetramer interface, affecting carbohydrate binding and oligomer formation, respectively. © 2016 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM)


Neto M.L.R.,University of Sao Paulo | Reis A.O.A.,University of Sao Paulo | de Abreu L.C.,University of Sao Paulo | Teixeira S.A.,Federal University of Ceará | And 4 more authors.
HealthMED | Year: 2012

Background: The expression 'bipolar disorder' refers to any of several psychological disorders of mood that alternate episodes of depression and mania. Also called manic depression or manic-depressive illness, it is a relatively common but unknown pathology that brings some stigmas for patients and provokes deleterious effects for their lives. This research aimed to comprehend actions, behaviors and emotions involved with bipolar disorder, through narratives of patient's personal and familiar histories. Methods: We surveyed 30 patients from a psychiatric service located in Aparecida, Paraiba, Brazil. Selected patients had bipolar disorder according to DSM-IV. For data collection, we used non-structured interview, approaching specific aspects related to bipolar disorder. Quantitative and qualitative analysis were done and Hamilton Rating Scale for Depression (HAMD) was used. Results: Most of patients presented depressive actions associated with moderate euphoria. 11 of them related familiar history of psychopathology. Mania and hippomania were prevalent on male gender, while psychotic symptoms overlay ate female. Conclusion: Patients lack a translation of behavioral and temperamental processes to minimize harm caused to their lives.


Torres A.,Federal University of Ceará | Pimenta A.,State University of Norte Fluminense | Braz-Filho R.,IRD Montpellier | Delprete P.G.,University do Vale do Acarau | And 3 more authors.
Magnetic Resonance in Chemistry | Year: 2010

Two unusual monoterpene indole alkaloids, stachyoside (1) and nor-methyl-23-oxo-correantoside (2), have been isolated from the aerial parts of Psychotria stachyoides. The structural elucidation of both compounds was performed by the aid of HRESIMS, FT-IR, and 1D- and 2D-NMR techniques including COSY, HSQC, HMBC, and NOESY. Copyright © 2010 John Wiley & Sons, Ltd.


Russi M.A.,Federal University of Santa Catarina | Vandresen-Filho S.,Federal University of Santa Catarina | Rieger D.K.,Federal University of Santa Catarina | Costa A.P.,Federal University of Santa Catarina | And 7 more authors.
Neurochemical Research | Year: 2012

Lectins are proteins capable of reversible binding to carbohydrates or glycoconjugates. In the central nervous system of mammals, lectins with affinity for mannose/glucose or galactose can modulate cellular communication. ConBr, a lectin isolated from the seeds of Canavalia brasiliensis, previously showed antidepressant effect in the forced swimming test in mice, with involvement of the monoaminergic system. In this study, we investigated the neuroprotective effects of ConBr against quinolinic acid (QA), a well-known NMDA agonist that produces severe neurotoxicity when administered in vivo. ConBr (10 μg/site) administered via intracerebroventricular (i.c.v.) showed a neuroprotective activity against seizures induced by QA (36.8 nmol/site; i.c.v.) when administered 15 min prior to QA, with a percentage of protection around 50%. ConBr was also able to significantly decrease the severity of the seizures but without changes in the latency of the first convulsion or the duration of the seizures. This effect was dependent on the structural integrity of the ConBr protein and its binding capacity to oligosaccharides residues. ConA, a lectin with high similarity to ConBr, did not reverse the QA-induced seizures. Moreover, ConBr was able to protect against hippocampal cell death caused by QA, which was measured by propidium iodide incorporation. QA caused activation of JNK2 and improved the phosphorylation of Ser831 and 845 on the AMPA receptor GluR1 subunit, and both of these effects were counteracted by ConBr. Our data suggest that the lectin ConBr may exert a modulatory action on NMDA receptors, which inhibits its activity in response to QA. © 2011 Springer Science+Business Media, LLC.


Figueiredo M.F.,University do Vale do Acarau | Bruno R.L.A.,Federal University of Paraiba | Barros e Silva A.E.,Federal University of Paraiba | Nascimento S.,Federal University of Paraiba | And 2 more authors.
Genetics and Molecular Research | Year: 2014

We investigated the karyotypes of 13 species of six sections of the genus Inga (Leguminosae-Mimosoideae) from Brazil. We used conventional Giemsa staining to identify numerical chromosomal variations and looked for karyotypic evolutionary patterns. The karyotypes generally had small chromosomes, varying from metacentric to submetacentric, with a basic number x = 13. Nine of the species showed 2n = 2x = 26 (I. thibaudiana, I. cayennensis, I. ingoides, I. edulis, I. vera, I. subnuda, I. striata, I. bollandii, and Inga sp), while 2n = 4x = 52 was seen in a population of Inga cylindrical and of I. capitata, and in five populations of I. laurina. Additionally, 2n = 8x = 104 was observed in a population of I. cayennensis. Eight of these counts were new, while the counts of 2n = 52 for I. laurina and 2n = 26 for I. marginata, I. vera, I. subnuda, and I. edulis confirmed previous studies. We did not find cytological stability among the sections studied, with occurrence of significant intra- and inter-specific numerical variations. We conclude that polyploidy has played a significant role in karyotypic evolution in this group and that it occurred independently in several sections of the genus. © FUNPEC-RP.


Luciano J.H.S.,Federal University of Ceará | Lima M.A.S.,Federal University of Ceará | Silveira E.R.,Federal University of Ceará | Vasconcelos I.M.,Federal University of Ceará | And 2 more authors.
Quimica Nova | Year: 2010

The new iridoid glucoside 10-O-vanilloyl-geniposidic acid has been isolated from the aerial parts of Alibertia myrciifolia along with hydroxyhopanone, 3α,22-dihydroxyhopane, ursolic acid, luteolin-3′,4′-dimethyl ether, caffeic acid and geniposidic acid. The structures of the isolated compounds were determined by means of mass spectrometry and nuclear magnetic resonance spectral analyses. The antifungal activities of the iridoids 10-O-vanilloyl-geniposidic acid and geniposidic acid were evaluated against the phytopathogenic fungi strains Colletotrichum gloeosporioides, Fusarium solani and Aspergillus niger.


Tresena N.L.,University do Vale do Acarau | Cavalcanti-Mata M.E.R.M.,Federal University of Campina Grande | Duarte M.E.M.,Federal University of Campina Grande | de Moraes A.M.,Empresa Estadual de Pesquisa Agropecuaria do Estado da Paraiba EMEPA PB
Cerne | Year: 2010

The objective of this research was to determine the more appropriate moisture content to the cryoconservation of the "yellow ipe" seeds when they are submitted to storage at the temperature of-196°C per five days. Samples of yellow ipe seeds were prepared with moisture content between 4 and 12%, wb. Test of germination were conducted and vigor of the seeds measured before and after the cryoconservation. The limit moisture content obtained was 4% w.b. for the cryoconservation of the yellow ipe seeds.


PubMed | Federal University of Ceará and University do Vale do Acarau
Type: | Journal: Biochimie | Year: 2016

Legume lectins have been widely studied and applied for many purposes in the last few decades, but many of their physiological aspects remain elusive. The Diocleinae legume subtribe, which includes intensively explored lectins, such as ConA, presents an unusual and extensive post-translational process which results in minor alterations in protein structure, in turn making its function elusive. Despite previous reports about Diocleinae precursor activity, no structural or functional analyses have ever been carried out to understand the impacts of post-translational processing relative to lectin structure and binding specificity. Here we analyzed the functionality of a non glycosylated, recombinantly expressed lectin precursor from Dioclea grandiflora through inhibition assays, corroborating the experimental data with structural information generated by molecular modeling, docking calculations and molecular dynamics simulations. We demonstrate that Diocleinae precursors are active and share the same carbohydrate specificity as mature lectins. At the same time, however, subtle structural alterations were detected and mostly result in an incomplete functionality of the precursor, as consequence of an immature binding site and an unstructured tetramer interface, affecting carbohydrate binding and oligomer formation, respectively.

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