http://repositorio.ufc.br/handle/riufc/325 2026-05-15T22:53:44Z http://repositorio.ufc.br/handle/riufc/64293 Título: New records of colleters in Chamaecrista (Leguminosae, Caesalpinioideae s.l.): structural diversity, secretion, functional role, and taxonomic importance Autor(es): Coutinho, Ítalo Antônio Cotta; Francino, Dayana Maria Teodoro; Meira, Renata Maria Strozi Alves Abstract: Premise of research. Colleters are structures that secrete a sticky product that covers and protects the shoot apex and floral buds. In Chamaecrista, colleters have been reported in the cotyledons of three species and on the leaves of all species belonging to sect. Absus subsect. Baseophyllum. Anatomical studies using taxonomic and phylogenetic approaches are necessary to evaluate the presence, diversity, and importance of colleters for Chamaecrista. Methodology. We analyzed 55 species of Chamaecrista belonging to five of the six sections of the genus. Samples from both herbarium- and field-collected material of young vegetative and reproductive meristems were used. The material was subjected to standard anatomical study by light microscopy and SEM, and secretion was evaluated by histochemical analyses. Pivotal results. Histochemical analyses for the total proteins, total polysaccharides, acid mucopolysaccharides, pectins/mucilage, and lipids generated positive results. Six types of colleters are described here: club shaped, racket shaped, long bottle shaped, short bottle shaped, long digitiform, and short digitiform. Sect. Apoucouita showed the short digitiform and club-shaped types and was the only section with colleters on the sepal margins. Most species of sect. Absus subsect. Absus presented the short bottle-shaped type, while all species from subsect. Baseophyllum presented the short digitiform and club-shaped types. Although the short bottle-shaped type was the most common among species from sect. Chamaecrista, the short digitiform and club-shaped types were also observed. The short bottle-shaped colleters were also found in sect. Grimaldia, while in sect. Xerocalyx only the digitiform type was found. Conclusions. The topography and components identified in the secretion of the colleters suggests that such structures may be involved in the protection of developing leaves and flowers. Five of the six types described in our study are novelties for Chamaecrista. The distribution of colleter structural diversity provides an important source of new data that may help to clarify the taxonomy and phylogeny of Chamaecrista. Tipo: Artigo de Periódico 2015-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/64289 Título: Ontogenesis, histochemistry and seasonal and luminous environmental characterization of secretory cavities in leaves of Myrcia splendens (Myrtaceae) Autor(es): Costa, Isabela Santiago Carneiro da; Lucena, Eliseu Marlônio Pereira de; Bonilla, Oriel Herrera; Radosavljevic, Aleksandar; Coutinho, Ítalo Antônio Cotta Abstract: Secretory cavities are structures that secrete compounds that protects plants against herbivory and pathogenic microorganisms. These cavities have been reported in many genera. However, there are few studies on secretory cavity ontogeny in the genus Myrcia (Myrtaceae) as well as the effects of luminosity and seasonality on such secretory cavities. Therefore, the objective of this is to provide new information regarding the ontogenesis, structure, histochemistry and effects of seasonality in M. splendens. We collected and analyzed leaves from ten M. splendens specimens exposed to sun and shade during both wet and dry seasons. Samples were subjected to standard anatomical techniques for light microscopy. Myrcia splendens has schizo-lysigenous ontogenesis with exudates composed of lipids, essential oils, oil-resins and alkaloids. The largest secretory cavities were found in leaves exposed to sun during the dry season. The presence of lipophilic compounds may be an important strategy to plant protection against herbivores. The seasonal variations observed in the leaf secretory cavities demonstrate the anatomical plasticity of such species to light and water availability. As total area of leaf cavities in M. splendens reflects the seasonal variation, this should be taken into account when aiming to produce crops meant to essential oils/alkaloids extractions. Tipo: Artigo de Periódico 2020-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/64283 Título: Microbial co-occurrence network and its key microorganisms in soil with permanent application of composted tannery sludge Autor(es): Ishimoto, Caroline Kie; Aono, Alexandre Hild; Nagai, James Shiniti; Sousa, Hério; Miranda, Ana Roberta Lima; Melo, Vania Maria Maciel; Mendes, Lucas William; Araujo, Fabio Fernando; Melo, Wanderley José de; Kuroshu, Reginaldo Massanobu; Esposito, Elisa; Araujo, Ademir Sergio Ferreira Abstract: Soil microbial communities act on important environmental processes, being sensitive to the application of wastes, mainly those potential contaminants, such as tannery sludge. Due to the microbiome complexity, graph-theoretical approaches have been applied to represent model microbial communities interactions and identify important taxa, mainly in contaminated soils. Herein, we performed network and statistical analyses into microbial 16S rRNA gene sequencing data from soil samples with the application of different levels of composted tannery sludge (CTS) to assess the most connected nodes and the nodes that act as bridges to identify key microbes within each community. The network analysis revealed hubs belonging to Proteobacteria in soil with lower CTS rates, while active degraders of recalcitrant and pollutant chemical hubs belonging to Proteobacteria and Actinobacteria were found in soils under the highest CTS rates. The majority of classified connectors belonged to Actinobacteria, but similarly to hubs taxa, they shifted from metabolic functional profile to taxa with abilities to degrade toxic compounds, revealing a soil perturbation with the CTS application on community organization, which also impacted the community modularity. Members of Actinobacteria and Acidobacteria were identified as both hub and connector suggesting their role as keystone groups. Thus, these results offered us interesting insights about crucial taxa, their response to environmental alterations, and possible implications for the ecosystem. Tipo: Artigo de Periódico 2021-01-01T00:00:00Z http://repositorio.ufc.br/handle/riufc/64280 Título: Cloning of cDNA sequences encoding cowpea (Vigna unguiculata) vicilins: Computational simulations suggest a binding mode of cowpea vicilins to chitin oligomers Autor(es): Rocha, Antônio J.; Sousa, Bruno L.; Girão, Matheus S.; Barroso-Neto, Ito L.; Júnior, José E. Monteiro; Oliveira, José Tadeu Abreu de; Nagano, Celso S.; Carneiro, Rômulo F.; Monteiro-Moreira, Ana C. O.; Rocha, Bruno A. M.; Freire, Valder N.; Grangeiro, Thalles B. Abstract: Vicilins are 7S globulins which constitute the major seed storage proteins in leguminous species. Variant vicilins showing differential binding affinities for chitin have been implicated in the resistance and susceptibility of cowpea to the bruchid Callosobruchus maculatus. These proteins are members of the cupin superfamily, which includes a wide variety of enzymes and non-catalytic seed storage proteins. The cupin fold does not share similarity with any known chitin-biding domain. Therefore, it is poorly understood how these storage proteins bind to chitin. In this work, partial cDNA sequences encoding β-vignin, the major component of cowpea vicilins, were obtained from developing seeds. Three-dimensional molecular models of β-vignin showed the characteristic cupin fold and computational simulations revealed that each vicilin trimer contained 3 chitin-binding sites. Interaction models showed that chito-oligosaccharides bound to β-vignin were stabilized mainly by hydrogen bonds, a common structural feature of typical carbohydrate-binding proteins. Furthermore, many of the residues involved in the chitin-binding sites of β-vignin are conserved in other 7S globulins. These results support previous experimental evidences on the ability of vicilin-like proteins from cowpea and other leguminous species to bind in vitro to chitin as well as in vivo to chitinous structures of larval C. maculatus midgut. Tipo: Artigo de Periódico 2018-01-01T00:00:00Z