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121.
Omer Koz Erdal Bedir Milena Masullo Ozgen Alankus-Caliskan Sonia Piacente 《Phytochemistry》2010,71(5-6):663-668
Four triterpene saponins, agrostemmosides A–D were isolated from the methanol extract of Agrostemma gracilis. The structures of the compounds were determined as 3-O-β-d-xylopyranosyloleanolic acid 28-O-β-d-glucopyranosyl-(1 → 2)-[β-d-xylopyranosyl-(1 → 6)]-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl ester, 3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyloleanolic acid 28-O-β-d-glucopyranosyl-(1 → 2)-[β-d-xylopyranosyl-(1 → 6)]-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl ester, 3-O-β-d-xylopyranosylechinocystic acid 28-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl ester, 3-O-β-d-xylopyranosylechinocystic acid 28-O-β-d-glucopyranosyl-(1 → 2)-[β-d-xylopyranosyl-(1 → 6)]-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl ester by a combination of one- and two-dimensional NMR techniques, and mass spectrometry. To the best of our knowledge this is the first phytochemical report on A. gracilis, and echinocystic acid saponins were encountered for the first time in Caryophyllaceae family. 相似文献
122.
Yongsheng Chen Imad Zein Everton Alen Brenner Jeppe Reitan Andersen Mathias Landbeck Milena Ouzunova Thomas Lübberstedt 《BMC plant biology》2010,10(1):12
Background
Reduced lignin content leads to higher cell wall digestibility and, therefore, better forage quality and increased conversion of lignocellulosic biomass into ethanol. However, reduced lignin content might lead to weaker stalks, lodging, and reduced biomass yield. Genes encoding enzymes involved in cell wall lignification have been shown to influence both cell wall digestibility and yield traits. 相似文献123.
Andersen JR Zein I Wenzel G Krützfeldt B Eder J Ouzunova M Lübberstedt T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(2):307-319
Forage quality of maize is influenced by both the content and structure of lignin in the cell wall. Phenylalanine Ammonia-Lyase (PAL) catalyzes the first step in lignin biosynthesis in plants; the deamination of L-phenylalanine to cinnamic acid. Successive enzymatic steps lead to the formation of three monolignols, constituting the complex structure of lignin. We have cloned and sequenced a PAL genomic sequence from 32 maize inbred lines currently employed in forage maize breeding programs in Europe. Low nucleotide diversity and excessive linkage disequilibrium (LD) was identified at this PAL locus, possibly reflecting selective constrains resulting from PAL being the first enzyme in the monolignol, and other, pathways. While the association analysis was affected by extended LD and population structure, several individual polymorphisms were associated with neutral detergent fiber (not considering population structure) and a single polymorphism was associated with in vitro digestibility of organic matter (considering population structure). 相似文献
124.
125.
Bezerra GA Oliveira TM Moreno FB de Souza EP da Rocha BA Benevides RG Delatorre P de Azevedo WF Cavada BS 《Journal of structural biology》2007,160(2):168-176
Plant lectins, especially those purified from species of the Leguminosae family, represent the best studied group of carbohydrate-binding proteins. The legume lectins from Diocleinae subtribe are highly similar proteins that present significant differences in the potency/efficacy of their biological activities. The structural studies of the interactions between lectins and sugars may clarify the origin of the distinct biological activities observed in this high similar class of proteins. In this way, this work presents a crystallographic study of the ConM and CGL (agglutinins from Canavalia maritima and Canavalia gladiata, respectively) in the following complexes: ConM/CGL:Man(alpha1-2)Man(alpha1-O)Me, ConM/CGL:Man(alpha1-3)Man(alpha1-O)Me and ConM/CGL:Man(alpha1-4)Man(alpha1-O)Me, which crystallized in different conditions and space group from the native proteins. The structures were solved by molecular replacement, presenting satisfactory values for R(factor) and R(free). Comparisons between ConM, CGL and ConA (Canavalia ensiformis lectin) binding mode with the dimannosides in subject, presented different interactions patterns, which may account for a structural explanation of the distincts biological properties observed in the lectins of Diocleinae subtribe. 相似文献
126.
Gorodkin J Cirera S Hedegaard J Gilchrist MJ Panitz F Jørgensen C Scheibye-Knudsen K Arvin T Lumholdt S Sawera M Green T Nielsen BJ Havgaard JH Rosenkilde C Wang J Li H Li R Liu B Hu S Dong W Li W Yu J Wang J Staefeldt HH Wernersson R Madsen LB Thomsen B Hornshøj H Bujie Z Wang X Wang X Bolund L Brunak S Yang H Bendixen C Fredholm M 《Genome biology》2007,8(4):R45-16
127.
Gonçalves Renata C. Carvalho Celso Carneiro Michels Monique Abatti Mariane R. Manfredini Andressa Silva Milena C. Dominguini Diogo Steckert Amanda Mina Francielle Streck Emílio Budni Josiane Dal-Pizzol Felipe 《Neurochemical research》2022,47(3):613-621
Neurochemical Research - Critical illness encompasses a wide spectrum of life-threatening clinical conditions requiring intensive care. Our objective was to evaluate cognitive, inflammatory and... 相似文献
128.
Eric?Roberto?Guimar?es?Rocha Aguiar Roenick Proveti Olmo Simona Paro Flavia Viana Ferreira Isaque?Jo?o?da?Silva de?Faria Yaovi?Mathias?Honore Todjro Francisco Pereira Lobo Erna Geessien Kroon Carine Meignin Derek Gatherer Jean-Luc Imler Jo?o Trindade Marques 《Nucleic acids research》2015,43(13):6191-6206
Virus surveillance in vector insects is potentially of great benefit to public health. Large-scale sequencing of small and long RNAs has previously been used to detect viruses, but without any formal comparison of different strategies. Furthermore, the identification of viral sequences largely depends on similarity searches against reference databases. Here, we developed a sequence-independent strategy based on virus-derived small RNAs produced by the host response, such as the RNA interference pathway. In insects, we compared sequences of small and long RNAs, demonstrating that viral sequences are enriched in the small RNA fraction. We also noted that the small RNA size profile is a unique signature for each virus and can be used to identify novel viral sequences without known relatives in reference databases. Using this strategy, we characterized six novel viruses in the viromes of laboratory fruit flies and wild populations of two insect vectors: mosquitoes and sandflies. We also show that the small RNA profile could be used to infer viral tropism for ovaries among other aspects of virus biology. Additionally, our results suggest that virus detection utilizing small RNAs can also be applied to vertebrates, although not as efficiently as to plants and insects. 相似文献
129.
130.
Structure and development of ‘witches' broom’ galls in reproductive organs of Byrsonima sericea (Malpighiaceae) and their effects on host plants
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A. L. A. Guimarães P. M. Neufeld L. D. R. Santiago‐Fernandes A. C. M. Vieira 《Plant biology (Stuttgart, Germany)》2015,17(2):493-504
Galls are anomalies in plant development of parasitic origin that affect the cellular differentiation or growth and represent a remarkable plant–parasite interaction. Byrsonima sericea DC. (Malpighiaceae) is a super host of several different types of gall in both vegetative and reproductive organs. The existence of galls in reproductive organs and their effects on the host plant are seldom described in the literature. In this paper, we present a novel study of galls in plants of the Neotropical region: the ‘witches' broom’ galls developed in floral structures of B. sericea. The unaffected inflorescences are characterised by a single indeterminate main axis with spirally arranged flower buds. The flower buds developed five unaffected brownish hairy sepals and five pairs of elliptical yellow elaiophores, five yellow fringed petals, 10 stamens and a pistil with superior tricarpellar and trilocular ovary. The affected inflorescences showed changes in architecture, with branches arising from the main axis and flower buds. The flower buds exhibited several morphological and anatomical changes. The sepals, petals and carpels converted into leaf‐like structures after differentiation. Stamens exhibited degeneration of the sporogenous tissue and structures containing hyphae and spores. The gynoecium did not develop, forming a central meristematic region, from which emerges the new inflorescence. In this work, we discuss the several changes in development of reproductive structures caused by witches' broom galls and their effects on reproductive success of the host plants. 相似文献