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991.
S. I. Allakhverdiev V. D. Kreslavski S. K. Zharmukhamedov R. A. Voloshin D. V. Korol’kova T. Tomo J.-R. Shen 《Biochemistry. Biokhimii?a》2016,81(3):201-212
The finding of unique Chl d- and Chl f-containing cyanobacteria in the last decade was a discovery in the area of biology of oxygenic photosynthetic organisms. Chl b, Chl c, and Chl f are considered to be accessory pigments found in antennae systems of photosynthetic organisms. They absorb energy and transfer it to the photosynthetic reaction center (RC), but do not participate in electron transport by the photosynthetic electron transport chain. However, Chl d as well as Chl a can operate not only in the light-harvesting complex, but also in the photosynthetic RC. The long-wavelength (Qy) Chl d and Chl f absorption band is shifted to longer wavelength (to 750 nm) compared to Chl a, which suggests the possibility for oxygenic photosynthesis in this spectral range. Such expansion of the photosynthetically active light range is important for the survival of cyanobacteria when the intensity of light not exceeding 700 nm is attenuated due to absorption by Chl a and other pigments. At the same time, energy storage efficiency in photosystem 2 for cyanobacteria containing Chl d and Chl f is not lower than that of cyanobacteria containing Chl a. Despite great interest in these unique chlorophylls, many questions related to functioning of such pigments in primary photosynthetic processes are still not elucidated. This review describes the latest advances in the field of Chl d and Chl f research and their role in primary photosynthetic processes of cyanobacteria. 相似文献
992.
Cécile Vanpé Lucie Debeffe Maxime Galan A. J. Mark Hewison Jean‐Michel Gaillard Emmanuelle Gilot‐Fromont Nicolas Morellet Hélène Verheyden Jean‐François Cosson Bruno Cargnelutti Joël Merlet Erwan Quéméré 《Oikos》2016,125(12):1790-1801
Dispersal is a key life‐history trait governing the response of individuals, populations and species to changing environmental conditions. In the context of global change, it is therefore essential to better understand the respective role of condition‐, phenotype‐ and genetic‐dependent drivers of dispersal behaviour. Although the importance of immune function and pathogen infestation in determining patterns of dispersal is increasingly recognised, no study to our knowledge has yet investigated the influence of immune gene variability on dispersal behaviour. Here, we filled this knowledge gap by assessing whether individual heterozygosity at five immune gene loci (one from the Major histocompatibility complex and four from encoding Toll‐like receptors) influences roe deer natal dispersal. We found that dispersal propensity was affected by immune gene diversity, suggesting potential pathogen‐mediated selection through over‐dominance. However, the direction of this effect differed between high and low quality individuals, suggesting that dispersal propensity is driven by two different mechanisms. In support of the condition‐dependent dispersal hypothesis, dispersal propensity increased with increasing body mass and, among high quality individuals only (standardized body mass > 18 kg), with increasing immune gene diversity. However, among poor quality individuals, we observed the opposite pattern such that dispersal propensity was higher for individuals with lower immune gene diversity. We suggest that these poor quality individuals expressed an emergency dispersal tactic in an attempt to escape a heavily infested environment associated with poor fitness prospects. Our results have potentially important consequences in terms of population genetics and demography, as well as host–pathogen evolution. 相似文献
993.
Li Hongbo Wang Xin Rengel Zed Ma Qinghua Zhang Fusuo Shen Jianbo 《Plant and Soil》2016,409(1-2):405-417
Plant and Soil - Nutrient patches in soil have a limited life-span, but the long-term costs and benefits of root foraging in agro-ecological systems are poorly understood. Maize (Zea mays L) was... 相似文献
994.
Chun-Long Li Mei Wang Xiao-Meng Wu Dong-Hua Chen Hong-Jun Lv Jian-Lin Shen Zhu Qiao Wei Zhang 《Plant physiology》2016,170(2):1090-1104
995.
Plant and Soil - Global nitrogen enrichment has been identified as a major environmental problem that poses a threat to ecosystem functioning. However, there is no consensus on the impact of... 相似文献
996.
Chaolei?Zhang Hongwei?Shen Xibin?Zhang Xue?Yu Han?Wang Shan?Xiao Jihui?Wang Zongbao?K.?ZhaoEmail author 《Biotechnology letters》2016,38(10):1733-1738
Objectives
To improve production of lipids and carotenoids by the oleaginous yeast Rhodosporidium toruloides by screening mutant strains.Results
Upon physical mutagenesis of the haploid strain R. toruloides np11 with an atmospheric and room temperature plasma method followed by chemical mutagenesis with nitrosoguanidine, a mutant strain, R. toruloides XR-2, formed dark-red colonies on a screening plate. When cultivated in nitrogen-limited media, XR-2 cells grew slower but accumulated 0.23 g lipids/g cell dry wt and 0.75 mg carotenoids/g CDW. To improve its production capacity, different amino acids and vitamins were supplemented. p-Aminobenzoic acid and tryptophan had beneficial effects on cell growth. When cultivated in nitrogen-limited media in the presence of selected vitamins, XR-2 accumulated 0.41 g lipids/g CDW and 0.69 mg carotenoids/g CDW.Conclusions
A mutant R. toruloides strain with improved production profiles for lipids and carotenoids was obtained, indicating its potential to use combined mutagenesis for a more productive phenotype.997.
Yonghong Meng Guiru Dong Chen Zhang Yuanyuan Ren Yuling Qu Weifeng Chen 《Biotechnology letters》2016,38(4):673-679
Objective
To study the effect of Ca2+ on glutamate dehydrogenase (GDH) and its role in poly-γ-glutamic acid (γ-PGA) synthesis in Bacillus natto HSF 1410.Results
When the concentration of Ca2+ varied from 0 to 0.1 g/l in the growth medium of B. natto HSF 1410, γ-PGA production increased from 6.8 to 9.7 g/l, while GDH specific activity and NH4Cl consumption improved from 183 to 295 U/mg and from 0.65 to 0.77 g/l, respectively. GDH with α-ketoglutarate as substrate primarily used NADPH as coenzyme with a K m of 0.08 mM. GDH was responsible for the synthesis of endogenous glutamate. The specific activity of GDH remained essentially unchanged in the presence of CaCl2 (0.05–0.2 g/l) in vitro. However, the specific activity of GDH and its expression was significantly increased by CaCl2 in vivo. Therefore, the regulation of GDH and PGA synthesis by Ca2+ is an intracellular process.Conclusion
Calcium regulation may be an effective approach for producing γ-PGA on an industrial scale.998.
999.
1000.
Anaerobic methane oxidation coupled to nitrite reduction can be a potential methane sink in coastal environments 总被引:1,自引:0,他引:1