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991.
The role of Rubisco and cell walls in the interspecific variation in photosynthetic capacity 总被引:2,自引:0,他引:2
Photosynthetic capacity is known to vary considerably among species. Its physiological cause and ecological significance have
been one of the most fundamental questions in plant ecophysiology. We studied the contents of Rubisco (a key enzyme of photosynthesis)
and cell walls in leaves of 26 species with a large variation in photosynthetic rates. We focused on photosynthetic nitrogen-use
efficiency (PNUE, photosynthetic rate per nitrogen), which can be expressed as the product of Rubisco-use efficiency (RBUE,
photosynthetic rate per Rubisco) and Rubisco nitrogen fraction (RNF, Rubisco nitrogen per total leaf nitrogen). RBUE accounted
for 70% of the interspecific variation in PNUE. The variation in RBUE was ascribed partly to stomatal conductance, and other
factors such as mesophyll conductance and Rubisco kinetics might also be involved. RNF was also significantly related to PNUE
but the correlation was relatively weak. Cell wall nitrogen fraction (WNF, cell wall nitrogen per total leaf nitrogen) increased
with increasing leaf mass per area, but there was no correlation between RNF and WNF. These results suggest that nitrogen
allocation to cell walls does not explain the variation in PNUE. The difference in PNUE was not caused by a sole factor that
was markedly different among species but by several factors each of which was slightly disadvantageous in low PNUE species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
992.
Stereocontrolled addition of carbon radicals to 4',5'-unsaturated uracil-nucleosides can be accomplished by using organoselenium reagents as a radical source. This provides a new method for C-C bond formation at the 5'-position. 相似文献
993.
H Kumamoto H Tanaka J Ogamino H Suzuki K Haraguchi T Miyasaka 《Nucleic acids symposium series》1999,(42):1-2
Naturally occurring ribonucleosides, uridine and adenosine, were converted to their 3'alpha-CH2CO2Me and 3'alpha-CH2PO(OPh)2 2',3'-dideoxy analogues. The present reaction sequence starts with oxidative cleavage of the 2',3'-cis-diol system, and involves radical-mediated reconstruction of furanose ring as the key step. 相似文献
994.
995.
Efficiency and regioselectivity (C-6 or C-5) in the lithiation of uridine derivatives were examined by using LDA (lithium diisopropylamide) and LTMP (lithium 2,2,6,6-tetramethylpiperidide). It revealed that rotation of the C-2' substituent caused steric hindrance on approaching the lithiating agent to the C-6 position, providing evidence that the lithiation takes place through their syn-conformers. 相似文献
996.
Kai Wang Ryo Tomura Wei Chen Miho Kiyooka Hinako Ishizaki Tomoyuki Aizu Yohei Minakuchi Masahide Seki Yutaka Suzuki Tatsuya Omotezako Ritsuko Suyama Aki Masunaga Charles Plessy Nicholas M. Luscombe Christelle Dantec Patrick Lemaire Takehiko Itoh Atsushi Toyoda Hiroki Nishida Takeshi A. Onuma 《Development, growth & differentiation》2020,62(6):450-461
997.
Hideyuki Matsuura Yosuke Yamamoto Misa Muraoka Kenji Akaishi Yasuhisa Hori Kanoko Uemura Naoki Tsuji Kazuo Harada Kazumasa Hirata Takeshi Bamba Hitoshi Miyasaka Kouichi Kuroda Mitsuyoshi Ueda 《Biotechnology progress》2013,29(5):1197-1202
The development of simple, portable, inexpensive, and rapid analytical methods for detecting and monitoring toxic heavy metals are important for the safety and security of humans and their environment. Herein, we describe the application of phytochelatin (PC) synthase, which plays a critical role in heavy metal responses in higher plants and green algae, in a novel fluorescent sensing platform for cadmium (Cd). We first created surface‐engineered yeast cells on which the PC synthase from Arabidopsis (AtPCS1) was displayed with retention of enzymatic activity. The general concept for the sensor is based on the Cd level‐dependent synthesis of PC2 from glutathiones by AtPCS1‐displaying yeast cells, followed by simple discriminative detection of PC2 via sensing of excimer fluorescence of thiol‐labeling pyrene probes. The intensity of excimer fluorescence increased in the presence of Cd up to 1.0 μM in an approximately dose‐dependent manner. This novel biosensor achieved a detection limit of as low as 0.2 μM (22.5 μg/L) for Cd. Although its use may be limited by the fact that Cu and Pb can induce cross‐reaction, the proposed simple biosensor holds promise as a method useful for cost‐effective screening of Cd contamination in environmental and food samples. The AtPCS1‐displaying yeast cells also might be attractive tools for dissection of the catalytic mechanisms of PCS. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1197–1202, 2013 相似文献