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1.
《Harmful algae》2009,8(1):167-174
Every year harmful algal blooms (HABs) cause serious impacts to local economies, coastal ecosystems, and human health on a global scale. It is well known that nutrient availability can influence important aspects of harmful algae biology and ecology, such as growth, toxin production, and life cycle stage, as well as bloom initiation, persistence and decline. Increases in the rate of supply of organic matter to ecosystems (eutrophication) carries many possible ramifications to coastal systems, including the potential for nutrient enrichment and the potential for stimulation of harmful algal blooms. Traditional studies on algal nutrition typically use either cultured isolates or community level assays, to examine nutrient uptake, nutrient preference, elemental composition, and other metrics of a species’ response to nutrients. In the last decade, technological advances have led to a great increase in the number of sequences available for critical harmful species. This, in turn, has led to new insights with regards to algal nutrition, and these advances highlight the promise of molecular technologies, and genomic approaches, to improving our understanding of algal nutrient acquisition and nutritional physiological ecology, in both cultures and field populations. With these developments increased monitoring of nutritional physiology in field populations of harmful algae will allow us to better discriminate how eutrophication impacts these groups. 相似文献
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《Current opinion in genetics & development》2000,10(3):245-246
A selection of World Wide Web sites relevant to papers published in this issue of Current Opinion in Genetics and Development. 相似文献
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H Souzu 《Archives of biochemistry and biophysics》1967,120(2):338-343
Following the freezing and thawing of yeast cells, it was shown that a polyphosphate in the cells was decomposed to orthophosphate and released from the cells. The release of phosphates was restricted to polyphosphate and orthophosphate native to the cells.Decomposition and liberation of polyphosphate in frozen-thawed cells was dependent upon the pH and was inhibited by an addition of sodium fluoride or heating of the cells.Polyphosphatase, also present in the cells, did not lose its activity by the freezing and thawing. Its behavior on decomposing polyphosphate coincided closely with that of polyphosphate decomposition in frozen-thawed cells, in the pH-activity curve, NaF sensitivity, and heat stability. 相似文献
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Zhang M. Zhang J. Jiao R. T. Yang X. E. Ji D. W. 《Russian Journal of Plant Physiology》2021,68(6):1115-1124
Russian Journal of Plant Physiology - Hyperaccumulating ecotype (HE) of Sedum alfredii Hance is a Zn/Cd hyperaccumulator, which can accumulate Zn in shoot up to 2% of dry weight, understanding the... 相似文献
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Jinhua Xiao Xianqin Wei Yi Zhou Zhaozhe Xin Yunheng Miao Hongxia Hou Jiaxing Li Dan Zhao Jing Liu Rui Chen Liming Niu Guangchang Ma Wenquan Zhen Shunmin He Jianxia Wang Xunfan Wei Weihao Dou Zhuoxiao Sui Dawei Huang 《遗传学报》2021,48(3):225-236
Figs and fig pollinators are one of the few classic textbook examples of obligate pollination mutualism. The specific dependence of fig pollinators on the relatively safe living environment with sufficient food sources in the enclosed fig syconia implies that they are vulnerable to habitat changes. However, there is still no extensive genomic evidence to reveal the evolutionary footprint of this long-term mutually beneficial symbiosis in fig pollinators. In fig syconia, there are also non-pollinator species. The non-pollinator species differ in their evolutionary and life histories from pollinators. We conducted comparative analyses on 11 newly sequenced fig wasp genomes and one previously published genome. The pollinators colonized the figs approximately 66.9 million years ago, consistent with the origin of host figs. Compared with nonpollinators, many more genes in pollinators were subject to relaxed selection. Seven genes were absent in pollinators in response to environmental stress and immune activation. Pollinators had more streamlined gene repertoires in the innate immune system, chemosensory toolbox, and detoxification system. Our results provide genomic evidence for the differentiation between pollinators and nonpollinators. The data suggest that owing to the long-term adaptation to the fig, some genes related to functions no longer required are absent in pollinators. 相似文献
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