{"id":6976,"date":"2019-06-25T11:36:31","date_gmt":"2019-06-25T14:36:31","guid":{"rendered":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/?page_id=6976"},"modified":"2019-07-02T10:49:24","modified_gmt":"2019-07-02T13:49:24","slug":"henrique-borges-zamengo-de-souza-ms","status":"publish","type":"page","link":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/dissertacoesteses\/henrique-borges-zamengo-de-souza-ms\/","title":{"rendered":"Emanuela de Oliveira Joaquim DR"},"content":{"rendered":"

\"faixapos6\"<\/a><\/h2>\n
\n

Emanuela de Oliveira Joaquim<\/h2>\n
\n

\"\"<\/a><\/p>\n

A aluna Emanuela de Oliveira Joaquim (bolsista CAPES) obteve o t\u00edtulo de Doutora pelo Programa de P\u00f3s-Gradua\u00e7\u00e3o em Biodiversidade Vegetal e Meio Ambiente do Instituto de Bot\u00e2nica de S\u00e3o Paulo, em 22 de fevereiro de 2018.\u00a0 Sua tese de doutorado intitulada: \u201cMetabolismo e localiza\u00e7\u00e3o de frutanos em Gomphrena marginata<\/em> Seub. (Amaranthaceae), end\u00eamica de Campos Rupestres\u201d teve orienta\u00e7\u00e3o da Dra. Maria Angela Machado de Carvalho.
\nA banca examinadora foi composta pela Dra. Maria Angela Machado de Carvalho (IBt), Dra. Moemy Gomes de Moraes (UFG), Dra. Mar\u00edlia Gaspar Mais (IBt), Dr. Augusto Cesar Franco (UNB) e Dra. Gladys Fl\u00e1via de Albuquerque Melo de Pinna\u00a0 (USP)<\/p>\n

\n

Metabolismo e localiza\u00e7\u00e3o de frutanos em Gomphrena marginata<\/em> Seub. (Amaranthaceae), end\u00eamica de Campos Rupestres<\/h3>\n
\n

ABSTRACT<\/strong><\/h4>\n

Campos rupestres<\/em> are mountain top ecosystems with rock outcrops, acid and nutritionally poor soils and often subjected to abiotic stresses. Gomphrena marginata<\/em> (Amaranthaceae) is endemic of campos rupestres<\/em> of the Espinha\u00e7o Mountain Range (MG) and listed as a rare species in Brazil. Several species of the Gomphrena<\/em> genus express the C4 photosynthetic pathway and present thickened underground systems that store considerable amounts of carbohydrates generally of the fructan type. A preliminary analysis suggested the presence of levan-type fructans in the underground systems of G. marginata, <\/em>atypical in eudicotyledonous, with only one report for Gomphrena macrocephala<\/em>, herbaceous species from Cerrado. The aim of this work was to analyze in plants of G. marginata<\/em>, fructan metabolism in different phenological phases, characterize the fructan chemical structure and the localization in the tissues, and characterize the photosynthetic metabolism. Plants were collected in the field at Serra de Itacambira (MG) during the phenological phases of dormancy (dry season), sprouting (beginning of rain season) and vegetative growth (end of rain season) in two phenological cycles. The activities of fructan biosynthetic and hydrolytic enzymes, the soluble sugars, osmotic potential and the water content were analyzed in different segments (proximal, median and distal) of the underground system. Carbohydrates were quantified colorimetrically and identified by HPAEC\/PAD and nuclear magnetic resonance. For anatomical analyses samples were fixed in FAA 70, included in historesin and stained in toluidine blue O. For identification of fructan crystals, samples were sectioned by freehand cross-sections, and visualized under polarized light. Histochemical analyses and scanning electron microscopy were also performed. The first phenological cycle presented few variations in sugar contents and enzymatic activities. 1-SST (sucrose:sucrose 1-fructosyltranferase), the fructosyltransferase which initiates fructan synthesis, presented activity only in the vegetative phase. 1-FFT (fructan:fructan 1-fructosyltranferase), responsible to promote the elongation and\/or reduction of the chain length, showed the highest activity at dormancy in the proximal segment and the FEH (fructan exohydrolase), showed higher activity in the sprouting phase, although no significant differences were found in the activities between phenological phases. In the second cycle, the lowest content of fructans was detected in the proximal segment at sprouting, when the highest contents of reducing sugars and highest osmotic potential values were also observed. FEH presented higher activity in the proximal segment at sprouting and vegetative phases. The median and distal segments did not present significant differences in the contents of total fructose and in enzymatic activities between phenological phases, indicating the preference to mobilize fructans accumulated in the proximal segment, near the aerial parts of the plant. HPAEC\u2013PAD analyses revealed the presence of glucose, fructose, sucrose, 1-kestose, 6-kestose, nystose and fructans with degree of polymerization up to approximately 50 fructose units. RMN of two-dimensional 1<\/sup>H\/13<\/sup>C HSQC and HMBC analyses showed the predominance of levan-type fructans, a linear molecule with \u03b2- 2,6 linkages, based on 6-kestose. Structural analyses of the underground organ revealed mainly a tuberous root, in which the vascular cylinder presents an unusual secondary growth pattern. Fructan crystals were visualized mostly in the cortex and vascular cylinder, and inside vessel elements. Leaves of G. marginata<\/em> are amphistomatic, with high vein density, and with tector trichomes on both surfaces and in considerable amounts in the leaf bases. The leaves show Kranz anatomy, which together with the isotopic ratio of -14\u2030, confirm the C4 photosynthetic metabolism in this species. The high concentration of fructan along with C4 metabolism indicate that this species is well adapted to environments exposed to the abiotic stresses and climatic seasonality occurring in campos rupestres<\/em>.
\nKeywords<\/strong>: Anatomy, C4, Kranz anatomy, levan, storage underground organ<\/p>\n

 <\/p>\n

RESUMO<\/strong><\/h4>\n

Campos rupestres s\u00e3o ecossistemas de topo de montanha que apresentam afloramentos rochosos, solos \u00e1cidos e pobres em nutrientes e que est\u00e3o frequentemente sujeitos a estresses ambientais. Gomphrena marginata<\/em> (Amaranthaceae) \u00e9 uma esp\u00e9cie end\u00eamica dos campos rupestres da Cadeia do Espinha\u00e7o (MG) que se encontra presente na lista de esp\u00e9cies raras do Brasil. Muitas esp\u00e9cies do g\u00eanero Gomphrena<\/em> possuem mecanismo fotossint\u00e9tico C4 com sistemas subterr\u00e2neos espessados que acumulam carboidratos, como por exemplo, os frutanos. Uma an\u00e1lise preliminar sugeriu a presen\u00e7a de frutano do tipo levano no sistema subterr\u00e2neo de G. marginata<\/em>, ocorr\u00eancia at\u00edpica em eudicotiled\u00f4neas, com apenas uma cita\u00e7\u00e3o em Gomphrena<\/em> macrocephala<\/em>, esp\u00e9cie herb\u00e1cea do Cerrado. Os objetivos do presente trabalho foram analisar em G. marginata<\/em> o metabolismo de frutanos em diferentes fases fenol\u00f3gicas da planta, caracterizar sua estrutura qu\u00edmica e sua localiza\u00e7\u00e3o nos tecidos, bem como caracterizar o seu metabolismo fotossint\u00e9tico. As plantas foram coletadas na Serra de Itacambira (MG) nas fases de dorm\u00eancia (seca), brota\u00e7\u00e3o (in\u00edcio das chuvas) e crescimento vegetativo (fim das chuvas), em dois ciclos fenol\u00f3gicos. A bioss\u00edntese e a degrada\u00e7\u00e3o dos frutanos, o conte\u00fado dos carboidratos sol\u00faveis, o potencial osm\u00f3tico e o teor de \u00e1gua foram analisados em diferentes segmentos (proximal, mediano e distal) do sistema subterr\u00e2neo. As quantifica\u00e7\u00f5es de carboidratos foram realizadas por m\u00e9todos colorim\u00e9tricos e sua identifica\u00e7\u00e3o por cromatografia (HPAEC\/PAD) e resson\u00e2ncia magn\u00e9tica nuclear. Para a an\u00e1lise anat\u00f4mica, amostras foram fixadas em FAA 70, inclu\u00eddas em historesina e coradas com azul de toluidina. Para identifica\u00e7\u00e3o dos cristais de frutanos, amostras dos sistemas subterr\u00e2neos foram seccionadas \u00e0 m\u00e3o livre e visualizadas sob luz polarizada. Foram realizados tamb\u00e9m testes histoqu\u00edmicos e an\u00e1lise por microscopia eletr\u00f4nica de varredura. No ciclo fenol\u00f3gico 1, houve poucas varia\u00e7\u00f5es nos conte\u00fados de a\u00e7\u00facares e nas atividades enzim\u00e1ticas. A enzima 1-SST (sacarose:sacarose 1- frutosiltransferase), que inicia a s\u00edntese de frutanos, apresentou atividade somente na fase \u00a0vegetativa. A 1-FFT (frutano:frutano 1-frutosiltransferase), enzima que promove tanto o alongamento como a diminui\u00e7\u00e3o das mol\u00e9culas, apresentou maior atividade na fase de dorm\u00eancia no segmento proximal, e a enzima de hidr\u00f3lise (FEH- frutano exohidrolase) apresentou maior atividade na fase de brota\u00e7\u00e3o, apesar de n\u00e3o apresentar diferen\u00e7a estat\u00edstica significativa entre as fases. No ciclo 2, o conte\u00fado mais baixo de frutanos ocorreu na regi\u00e3o proximal do sistema subterr\u00e2neo, na fase de brota\u00e7\u00e3o, que tamb\u00e9m apresentou maiores teores de a\u00e7\u00facares redutores e potencial osm\u00f3tico menos negativo. A FEH apresentou maior atividade no segmento proximal nas fases de brota\u00e7\u00e3o e de crescimento vegetativo. Os segmentos mediano e distal n\u00e3o apresentaram altera\u00e7\u00f5es expressivas no teor de frutose total e nas atividades enzim\u00e1ticas entre as fases, indicando a prefer\u00eancia por mobilizar frutanos estocados nos segmentos mais pr\u00f3ximos \u00e0 parte a\u00e9rea. Nas an\u00e1lises em HPAEC\u2013PAD foram identificados glicose, frutose, sacarose, 1-cestose, 6-cestose, nistose e frutanos com grau de polimeriza\u00e7\u00e3o de at\u00e9 aproximadamente 50 unidades de frutose. Dados das an\u00e1lises bidimensionais de RMN 1<\/sup>H\/13<\/sup>C HSQC e HMBC mostraram que o frutano predominante \u00e9 o levano, uma mol\u00e9cula linear com liga\u00e7\u00f5es \u03b2- 2,6, baseada no trissacar\u00eddeo 6-cestose. An\u00e1lises estruturais demonstraram que o sistema subterr\u00e2neo \u00e9 composto majoritariamente de uma raiz tuberosa com potencial gem\u00edfero, no qual o cilindro vascular apresenta um crescimento secund\u00e1rio n\u00e3o usual. Cristais de frutanos foram visualizados principalmente no c\u00f3rtex, no cilindro vascular e no interior dos elementos de vaso. Folhas de G. marginata<\/em> s\u00e3o anfiestom\u00e1ticas, apresentam vena\u00e7\u00f5es bem densas, tricomas tectores em ambas as faces e em grande abund\u00e2ncia na base foliar. Apresentam anatomia Kranz que, juntamente com a raz\u00e3o isot\u00f3pica de -14\u2030, confirma o metabolismo fotossint\u00e9tico C4 nesta esp\u00e9cie. A concentra\u00e7\u00e3o elevada de frutanos e a presen\u00e7a do metabolismo fotossint\u00e9tico C4, evidenciam a adapta\u00e7\u00e3o desta esp\u00e9cie a ambientes sujeitos aos estresses ambientais e \u00e0 sazonalidade clim\u00e1tica ocorrentes nos campos rupestres.
\nPalavras-chave<\/strong>: Anatomia, anatomia Kranz, C4, levano, \u00f3rg\u00e3os subterr\u00e2neos de reserva<\/p>\n

<\/h4>\n
\n

\"pdf_grande\"<\/a>Emanuela de Oliveira Joaquim <\/a>
\nMetabolismo e localiza\u00e7\u00e3o de frutanos em Gomphrena marginata<\/em> Seub. (Amaranthaceae), end\u00eamica de Campos Rupestres<\/a><\/p>\n

\n

\u00a0VOLTAR AS DISSERTA\u00c7\u00d5ES E TESES<\/a><\/strong><\/p>\n

\n","protected":false},"excerpt":{"rendered":"

Emanuela de Oliveira Joaquim A aluna Emanuela de Oliveira Joaquim (bolsista CAPES) obteve o t\u00edtulo de Doutora pelo Programa de P\u00f3s-Gradua\u00e7\u00e3o em Biodiversidade Vegetal e Meio Ambiente do Instituto de Bot\u00e2nica de S\u00e3o Paulo, em 22 de fevereiro de 2018.\u00a0 Sua tese de doutorado intitulada: \u201cMetabolismo e localiza\u00e7\u00e3o de frutanos em Gomphrena marginata Seub. (Amaranthaceae), […]<\/p>\n","protected":false},"author":103,"featured_media":0,"parent":249,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/6976"}],"collection":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/users\/103"}],"replies":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/comments?post=6976"}],"version-history":[{"count":6,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/6976\/revisions"}],"predecessor-version":[{"id":7005,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/6976\/revisions\/7005"}],"up":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/249"}],"wp:attachment":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/media?parent=6976"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}