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71.
72.
Paolina Garbeva Mariana Avalos Dana Ulanova Gilles P. van Wezel Jeroen S. Dickschat 《Environmental microbiology》2023,25(9):1565-1574
Geosmin may be the most familiar volatile compound, as it lends the earthy smell to soil. The compound is a member of the largest family of natural products, the terpenoids. The broad distribution of geosmin among bacteria in both terrestrial and aquatic environments suggests that this compound has an important ecological function, for example, as a signal (attractant or repellent) or as a protective specialized metabolite against biotic and abiotic stresses. While geosmin is part of our everyday life, scientists still do not understand the exact biological function of this omnipresent natural product. This minireview summarizes the current general observations regarding geosmin in prokaryotes and introduces new insights into its biosynthesis and regulation, as well as its biological roles in terrestrial and aquatic environments. 相似文献
73.
Neuza Domingues André R. A. Marques Rita Diogo Almeida Calado Inês S. Ferreira Cristiano Ramos José Ramalho Maria I. L. Soares Telmo Pereira Luís Oliveira José R. Vicente Louise H. Wong Inês C. M. Simões Teresa M. V. D. Pinho e Melo Andrew Peden Cláudia Guimas Almeida Clare E. Futter Rosa Puertollano Winchil L. C. Vaz Otília V. Vieira 《Traffic (Copenhagen, Denmark)》2023,24(7):284-307
74.
A thorough analysis of glass containing Eu2O3 and Dy2O3, or Eu2O3, Dy2O3, and CuO melted together with nanodiamond powder was pursued based on measurements of optical absorption, photoluminescence (PL) emission and excitation spectra, and colorimetry. Nanodiamond facilitated the stabilization of Cu+ and Eu2+ ions with blue-emitting characteristics that, along with yellow-emitting Dy3+ and red-emitting Eu3+ led to the white light-emitting glass. Novel intensity notations implemented in intensity-based spectral ratios, and difference intensity correlation analysis were proposed for the assessment of PL properties. The chromaticity and correlated colour temperature of the emission were ultimately investigated as a two-parametric problem based on: (1) the different ionic components; and (2) the various excitation wavelengths employed. The optical analysis approach adds to the characterization methods to further fundamental understanding and provide helpful analytical tools for designing materials for tunable white light-emitting devices. 相似文献
75.
A protein kinase activity in chorionated oocytes of Rhodnius prolixus phosphorylates in vitro vitellin (VT), the major yolk protein. Phosphatase inhibitors including NaF, sodium vanadate, beta-glycerophosphate and okadaic acid did not alter the protein phosphorylation profile to a visible extent. Among the exogenous protein substrates tested, casein was readily phosphorylated, but histones were not. Several different protein kinase activators, including cAMP, Ca2+ plus calmodulin, Ca2+ plus diolein and phosphatidylserine, were added to the reaction media but spermidine was the only effective one, inducing a 2-fold increase in the phosphorylation of VT. A strong inhibition was obtained with nanomolar levels of heparin. The enzyme could also accept GTP as the phosphate donor instead of ATP. These properties identify the major protein kinase activity as a type II casein kinase (CK II). The pH dependence and the effects of mono- and divalent cations on VT phosphorylation were also studied. Gel filtration revealed only one peak of protein kinase activity, with a molecular mass of 170 K, similar to values previously reported in the literature for CK IIs from other organisms. 相似文献
76.
Inflorescence-specific genes from Arabidopsis thaliana encoding glycine-rich proteins 总被引:6,自引:0,他引:6
D.E. de Oliveira L.O. Franco C. Simoens J. Seurinck J. Coppieters J. Botterman M. Van Montagu 《The Plant journal : for cell and molecular biology》1993,3(4):495-507
Genomic and cDNA clones for three inflorescence-specific genes from Arabidopsis thaliana were isolated and characterized. The genes are tandemly organized in the genome on a 10 kb fragment. The expression of these genes is coordinately regulated in a developmental and organ-specific pattern. They are expressed predominantly in anthers at the later stage of flower development. The primary structure of the encoded gene products exhibits comparable features consisting of a hydrophobic domain at the N-terminal region followed by repeated glycine-rich motifs. Little homology is observed either between the glycine-rich domain of the three genes or with previously described glycine-rich proteins from other plant species. 相似文献
77.
Joana Pais De Faria Vitor H. Paiva Sara N. Veríssimo Catarina S. Lopes Rita Soares João Oliveira Ivo dos Santos Ana C. Norte Jaime A. Ramos 《Ibis》2023,165(1):312-321
Gulls, as largely flexible opportunistic individuals, have been increasingly breeding in many cities around the world, but it is still unclear whether urban habitats are of equal or higher quality than traditional natural habitats or represent an ecological trap with immediate reproductive benefits but longer-term detrimental consequences to health. Here we present a study of breeding parameters (nest density, egg dimensions, clutch size, hatching success and adult body condition) and physiological parameters (erythrocyte sedimentation rate, heterophil/lymphocyte ratio, haemoglobin concentration and measurements of oxidative stress) as indicators of the general health condition of Yellow-legged Gull Larus michahellis adults and chicks from natural and urban colonies. Yellow-legged Gulls in the largest urban area (Porto) laid smaller eggs and clutches, showed a significantly lower occurrence of inflammatory processes in chicks, and showed a slower early chick growth than in the natural colony of Deserta. This suggests that urban gulls might be facing important trade-offs between the advantages of breeding in lower density urban colonies, with fewer intraspecific interactions and a lower disease transmission probability, and the disadvantages of having an anthropogenic diet usually lower in nutritional value. 相似文献
78.
Douglas Maciel Reisla Oliveira Paulo Enrique Cardoso Peixoto 《Ethology : formerly Zeitschrift fur Tierpsychologie》2023,129(2):99-106
Sexually selected traits, such as male weapons, are highly variable in shape and size across species. However, little is known about the mechanisms that may govern this variation. Because males with greater investment in weapon size tend to win more fights, but also pay higher costs related to weapon development and maintenance, larger weapons should be expected only in species in which victory in male–male fights generate reproductive benefits that outweigh investment costs. Here, we hypothesized that the reproductive characteristics that increase the chances of winners to access females or to fertilize eggs will favor the evolution of larger weapons. To evaluate this hypothesis, we conducted a meta-analysis using arthropods as model organisms. To measure investment in weapon size, we gathered both Pearson correlation coefficient and the standardized (but non centralized) slope values for the relationship between weapon size and body size. We found that none of the reproductive characteristics we investigated was related to male weapon size. Thus, it seems that greater certainty of accessing a female or fertilizing female eggs with a victory does not modulate the investment in male weapon size. Perhaps the cost–benefit ratio between weapon size investment and reproductive success is not the main factor driving the variation in weapon size. 相似文献
79.
Summary An aqueous two-phase system of polyethylene glycol (PEG) and potassium phosphate was developed for extraction of a cutinase from cell debris of a recombinant Escherichia coli strain. Basic studies to identify the primary factors which affect cutinase partition, namely the influence of polymer molecular weight, polymer concentration and pH were carried out using a purified preparation of the cutinase. The enzyme partition coefficient was enhanced with decreasing PEG molecular weight, increasing tie-line length and pH. 相似文献
80.
Varilla González Jean David Macedo Alves Flávio Bagnatori Sartori Ângela Lúcia de Oliveira Arruda Rosani do Carmo 《Journal of plant research》2023,136(4):453-481
Journal of Plant Research - The Pterocarpus clade includes 23 genera previously attributed to different Fabaceae tribes. The recent rearrangements of many genera in the clade do not recognize... 相似文献