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1.
MethodsX ; 12: 102694, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38633418

RESUMO

In contrast to traditional beach profiling methods like topographic surveys and GNSS, which pose significant challenges in terms of cost and time, this research underscores the efficiency, cost-effectiveness, and simplicity of terrestrial photogrammetry employing the Structure from Motion-Multi View Stereo (SfM-MVS) method. Notably, this approach enables the utilization of commonplace devices such as smartphones for data capture. The methodology integrates a 12-megapixel camera for image acquisition, processed through Agisoft Metashape Professional software, and validated for accuracy using ground control points (GCPs) and checkpoints (CKPs) calibrated via GNSS. Findings reveal substantial disparities in positional accuracy according to the Ground Control Points distribution. The study underscores the critical role of strategically distributing GCPs and CKPs in effectively mapping coastal areas, thus affirming the potential of SfM-MVS as a powerful and accessible tool for coastal monitoring initiatives. This research contributes significantly to advancing the efficiency and accessibility of beach profile monitoring, offering invaluable insights for researchers and practitioners in coastal management and environmental conservation efforts.•A simplified beach profile modeling methodology is proposed.•The method is faster and more cost-effective than traditional surveys (RTK GNSS, lidar, RPA).•The study highlights the importance of GCP and CKP distribution in enhancing SfM-MVS accuracy for coastal mapping.

2.
Int J Biol Macromol ; 140: 761-770, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31434004

RESUMO

Lipase B from Candida antarctica (CalB) is the most widely used lipase, including in many industrial sectors, such as in biodiesel and pharmaceuticals production. CalB has been produced by heterologous expression using Pichia pastoris under PGK constitutive promoter (named LipB). Here, we have studied the structural features of commercial CalB and LipB enzymes using circular dichroism and fluorescence under different conditions. In the presence of denaturing agents CalB was more stable than LipB, in contrast, at increasing temperatures, LipB was more thermostable than CalB. Mass spectrometry data indicates that both enzymes have an insertion of amino acids related to α-factor yeast signal, however LipB enzyme showed the addition of nine residues at the N-terminal while CalB showed only four residues. Molecular modeling of LipB showed the formation of an amphipathic α-helix in N-terminal region that was not observed in CalB. This data suggests that this new α-helix possess could be involved in LipB thermostability. These results associated with new structural studies may provide information to the design of novel biocatalysts.


Assuntos
Candida/enzimologia , Proteínas Fúngicas/química , Lipase/química , Proteínas Recombinantes de Fusão , Sequência de Aminoácidos , Candida/genética , Ativação Enzimática , Estabilidade Enzimática , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Hidrólise , Lipase/genética , Lipase/isolamento & purificação , Lipase/metabolismo , Modelos Moleculares , Conformação Proteica , Relação Estrutura-Atividade , Temperatura , Termodinâmica
3.
Anim Reprod Sci ; 145(1-2): 29-39, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24418125

RESUMO

Thiol groups of cysteine residues represent redox centers involved in multiple biological functions. It has been postulated that changes in the redox status of mammalian epididymal spermatozoa contribute to the sperm maturation process. The present work shows the thiol-disulfide protein profile of stallion epididymal spermatozoa achieved by two-dimension electrophoresis and MALDI-TOF/TOF mass spectrometry of proteins labeled with a thiol-reactive fluorescent tag, monobromobimane. Our results have shown the formation of disulfide bonds in several sperm protein fractions during the epididymal maturation process. The majority of the oxidized thiol sperm proteins identified correspond to structural molecules of the flagellum (as the outer dense fiber-1 protein - ODF1), followed by glycolytic enzymes (as glyceraldehyde-3-phosphate dehydrogenase spermatogenic), antioxidant protectors (as glutathione S-transferase and phospholipid hydroperoxide glutathione peroxidase - PHGPx). The magnitude of the thiol oxidation differs between proteins, and was more drastic in polypeptides with molecular weights of up to 33kDa, identified as ODF1 and PHGPx. A kinase anchor protein, a voltage-dependent anion channel protein and a zona pellucida-binding protein were also found in the polypeptide samples that contained oxidized SH groups. These proteins may be modified or controlled by the mechanisms involved in the cysteine-redox changes, corroborating the belief that a correct degree of protein oxidation is required for the stabilization of sperm structure, protection against oxidative damage, induction of progressive sperm motility and fertilization.


Assuntos
Dissulfetos/análise , Cavalos , Proteínas de Plasma Seminal/análise , Espermatozoides/química , Compostos de Sulfidrila/análise , Animais , Eletroforese em Gel Bidimensional , Cavalos/metabolismo , Masculino , Proteoma/análise , Proteoma/metabolismo , Proteínas de Plasma Seminal/química , Proteínas de Plasma Seminal/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Recuperação Espermática/veterinária , Espermatozoides/metabolismo
4.
Braz. j. med. biol. res ; 45(2): 118-124, Feb. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-614572

RESUMO

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1 percent, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78 percent. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.


Assuntos
Animais , Feminino , Albizzia/química , Besouros/efeitos dos fármacos , Proteínas de Armazenamento de Sementes/toxicidade , Sementes/química , Larva/efeitos dos fármacos
5.
Braz J Med Biol Res ; 45(2): 118-24, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22267002

RESUMO

Seed coat is a specialized maternal tissue that interfaces the embryo and the external environment during embryogenesis, dormancy and germination. In addition, it is the first defensive barrier against penetration by pathogens and herbivores. Here we show that Albizia lebbeck seed coat dramatically compromises the oviposition, eclosion and development of the bruchid Callosobruchus maculatus. Dietary supplementation of bruchid larvae with A. lebbeck seed coat flour causes severe weight loss and reduces survival. By means of protein purification, mass spectrometry and bioinformatic analyses, we show that chitin-binding vicilins are the main source of A. lebbeck tegumental toxicity to C. maculatus. At concentrations as low as 0.1%, A. lebbeck vicilins reduce larval mass from 8.1 ± 1.7 (mass of control larvae) to 1.8 ± 0.5 mg, which corresponds to a decrease of 78%. Seed coat toxicity constitutes an efficient defense mechanism, hindering insect predation and preventing embryo damage. We hypothesize that A. lebbeck vicilins are good candidates for the genetic transformation of crop legumes to enhance resistance to bruchid predation.


Assuntos
Albizzia/química , Besouros/efeitos dos fármacos , Proteínas de Armazenamento de Sementes/toxicidade , Sementes/química , Animais , Feminino , Larva/efeitos dos fármacos
6.
Braz J Med Biol Res ; 39(11): 1435-44, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17146556

RESUMO

Evidence based on immunological cross-reactivity and anti-diabetic properties has suggested the presence of insulin-like peptides in plants. The objective of the present study was to investigate the presence of insulin-like proteins in the leaves of Bauhinia variegata ("pata-de-vaca", "mororó"), a plant widely utilized in popular medicine as an anti-diabetic agent. We show that an insulin-like protein was present in the leaves of this plant. A chloroplast protein with a molecular mass similar to that of bovine insulin was extracted from 2-mm thick 15% SDS-PAGE gels and fractionated with a 2 x 24 cm Sephadex G-50 column. The activity of this insulin-like protein (0.48 mg/mL) on serum glucose levels of four-week-old Swiss albino (CF1) diabetic mice was similar to that of commercial swine insulin used as control. Further characterization of this molecule by reverse-phase hydrophobic HPLC chromatographic analysis as well as its antidiabetic activity on alloxan-induced mice showed that it has insulin-like properties. Immunolocalization of the insulin-like protein in the leaves of B. variegata was performed by transmission electron microscopy using a polyclonal anti-insulin human antibody. Localization in the leaf blades revealed that the insulin-like protein is present mainly in chloroplasts where it is also found associated with crystals which may be calcium oxalate. The presence of an insulin-like protein in chloroplasts may indicate its involvement in carbohydrate metabolism. This finding has strengthened our previous results and suggests that insulin-signaling pathways have been conserved through evolution.


Assuntos
Bauhinia/química , Cloroplastos/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/isolamento & purificação , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/isolamento & purificação , Folhas de Planta/química , Animais , Autoanticorpos/sangue , Bauhinia/citologia , Bovinos , Cloroplastos/ultraestrutura , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Hipoglicemiantes/uso terapêutico , Imunoglobulina G/sangue , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/uso terapêutico , Camundongos , Microscopia Eletrônica de Transmissão , Folhas de Planta/citologia
7.
Braz. j. med. biol. res ; 39(11): 1435-1444, Nov. 2006. ilus, graf
Artigo em Inglês | LILACS | ID: lil-437826

RESUMO

Evidence based on immunological cross-reactivity and anti-diabetic properties has suggested the presence of insulin-like peptides in plants. The objective of the present study was to investigate the presence of insulin-like proteins in the leaves of Bauhinia variegata ("pata-de-vaca", "mororó"), a plant widely utilized in popular medicine as an anti-diabetic agent. We show that an insulin-like protein was present in the leaves of this plant. A chloroplast protein with a molecular mass similar to that of bovine insulin was extracted from 2-mm thick 15 percent SDS-PAGE gels and fractionated with a 2 x 24 cm Sephadex G-50 column. The activity of this insulin-like protein (0.48 mg/mL) on serum glucose levels of four-week-old Swiss albino (CF1) diabetic mice was similar to that of commercial swine insulin used as control. Further characterization of this molecule by reverse-phase hydrophobic HPLC chromatographic analysis as well as its antidiabetic activity on alloxan-induced mice showed that it has insulin-like properties. Immunolocalization of the insulin-like protein in the leaves of B. variegata was performed by transmission electron microscopy using a polyclonal anti-insulin human antibody. Localization in the leaf blades revealed that the insulin-like protein is present mainly in chloroplasts where it is also found associated with crystals which may be calcium oxalate. The presence of an insulin-like protein in chloroplasts may indicate its involvement in carbohydrate metabolism. This finding has strengthened our previous results and suggests that insulin-signaling pathways have been conserved through evolution.


Assuntos
Animais , Bovinos , Camundongos , Bauhinia/química , Cloroplastos/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/isolamento & purificação , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/isolamento & purificação , Folhas de Planta/química , Autoanticorpos/sangue , Bauhinia/citologia , Cromatografia Líquida de Alta Pressão , Cloroplastos/ultraestrutura , Eletroforese em Gel de Poliacrilamida , Hipoglicemiantes/uso terapêutico , Imunoglobulina G/sangue , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/uso terapêutico , Microscopia Eletrônica de Transmissão , Folhas de Planta/citologia
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