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51.
The complexes [Re{MeN(CH2CH2O)(CH2CH2OH)-κ3N,O,O}(CO)3] (1), [Re{N(CH2CH2O)(CH2CH2OH)2-κ3N,O,O}(CO)3] (2), [Me3NH]2[(OC)3Re{N(CH2CO2)2-κ3N,O,O}CH2CH2{N(CH2CO2)2-κ3N,O,O}Re(CO)3] (3), [Me3NH]2[Re2{μ2-2,6-(O2C)2(C5H3N)-κ3N,O,O}2(CO)6] (4) and [Re2{μ2-2,6-(OCH2)(C5H3N)(CH2OH)-κ2N,O}2(CO)6] (5) were synthesized in high yields via the reactions of [Re2(CO)10] and Me3NO with MeN(CH2CH2OH)2, N(CH2CH2OH)3, EDTA, pyridine-2,6-dicarboxylic acid and pyridine-2,6-dimethanol, respectively. Complexes 1-5 were characterized by IR and 1H NMR spectroscopy, elemental analysis and X-ray crystallography. 相似文献
52.
The VASP-Spred-Sprouty domain puzzle 总被引:3,自引:0,他引:3
Sprouty-related proteins with an EVH1 domain (Spreds) belong to a new protein family harboring a conserved N-terminal EVH1 domain, which is related to the VASP (vasodilator-stimulated phosphoprotein) EVH1 domain (Enabled/VASP homology 1 domain) and a C-terminal Sprouty-related domain, typical for Sprouty proteins. Spreds were, like Sproutys, initially discovered as inhibitors of the Ras/MAPK pathway, and the SPR (Sprouty-related) domains of both protein families seem to be very important for many protein interactions and cellular processes. VASP was initially characterized as a proline-rich substrate of protein kinases A and G in human platelets and later shown to be a scaffold protein, regulating both signal transduction pathways and the actin filament system. The VASP-EVH1 domain is known to bind specifically to a FP(4) binding motif, which is, for example, present in the focal adhesion proteins vinculin and zyxin. In this review we give a structural and functional overview on these three protein families and ask whether nature plays a modular protein domain puzzle with stable exchangeable elements or if these closely related domains have various functions when pasted in a different protein context. 相似文献
53.
Tannins occur commonly in the wastewaters from forestry, plant medicine, paper and leather industries. The treatment of this
kind of wastewaters, including settling and biodegradation, is usually difficult because tannins are highly soluble in water
and would inhibit the growth of microorganisms in activated sludge. The objective of this study is to investigate biodegradability
of tannin-containing wastewaters, so as to characterize the pollution properties of such wastewaters and provide a reference
for their biological treatment in wastewater treatment plants. The research was typified by using the wastewater collected
from vegetable tanning process in leather industry. A model was developed to describe the activated sludge process, and the
biodegradation kinetics of vegetable tanning wastewater (VET wastewater) was studied. It was found that the biodegradability
of tannin-containing wastewater varies heavily with the content of tannins in wastewater. The biodegradation of VET wastewater
with tannin content around 4,900 mg/l occurred inefficiently due to the inhibition of tannins to the activated sludge process,
and only 34.7% of biodegradation extent was reached in 14 days of incubation. The optimal biodegradability of VET wastewater
was observed when its tannin content was diluted to 490 mg/l, where the COD and tannin removals reached 51.3% and 45.1% respectively
in 6 days. Hence, it is suggested that a proper control of tannin content is necessary to achieve an effective biodegradation
of tannin-containing wastewaters in wastewater treatment plants. 相似文献
54.
不同性别类型黄瓜ACC合酶基因的单核苷酸多态性标记和酶切扩增长度多态性标记 总被引:7,自引:0,他引:7
黄瓜的性别分化与乙烯密切相关,1-氨基环丙烷-1-羧酸(ACC)合酶是乙烯生物合成过程中的关键酶.根据ACC合酶基因家族的保守序列设计PCR引物,从8个不同性别类型(雌雄同株、强雌性和全雌性)黄瓜品种中克隆了长度为1188bp的ACC合酶基因(CS-ACS2)片段(GenBank登记号为:DQ115884~DQ115886和DQ115875~DQ115879).经测序分析,3个雌雄同株性别类型品种的序列完全相同.与之相比,5个强雌性和全雌性品种中存在8个单核苷酸多态性(SNPs)标记,SNPs标记为4个A←→G和4个T←→C之间的转换.在8个SNPs中,有1个SNP位于内含子区域,其余7个SNPs都位于外显子区域.在7个位于外显子区域的SNPs中,有3个为非编码区的SNPs,4个为cSNPs.而在4个cSNPs中,有3个导致了编码的氨基酸序列改变.研究结果表明,与雌雄同株性别类型相比,雌性系中均存在单核苷酸的变异,这提示ACC合酶基因CS-ACS2的单核苷酸变异可能与黄瓜雌性系的发生形成有关.另一方面,根据SNP多态性还发展了一个酶切扩增长度多态性(CAPS)标记C-MT700.利用CAPS标记C-MT700能将强雌性优良品种MT-705与其他黄瓜品种相区别,该标记在黄瓜育种生产上具有一定的应用价值.此外,研究获得的SNPs标记和CAPS标记丰富了黄瓜的分子标记种类. 相似文献
55.
Gao Kai Liu Meiyou Li Yuan Wang Lei Zhao Chao Zhao Xian Zhao Jinyi Ding Yi Tang Haifeng Jia Yanyan Wang Jingwen Wen Aidong 《Journal of molecular histology》2021,52(3):449-459
Journal of Molecular Histology - Currently, the excessive activation of N-methyl-D-aspartate receptors (NMDARs) is considered to be a crucial mechanism of brain injury. Lycium barbarum A (LyA) is a... 相似文献
56.
Crystallization and main-chain structure of neutral protease from Streptomyces caespitosus 总被引:1,自引:0,他引:1
A neutral protease, i.e., a zinc-containing metalloendoprotease from Streptomyces caespitosus, has been crystallized using acetone as a precipitating agent. The crystals diffract to better than 1.5 A resolution when a rotating anode X-ray generator is used as an X-ray source. Protein phase angles were calculated by the multiple isomorphous replacement method using two heavy-atom derivatives (HgCl2 and CH3HgCl). A 6 A resolution electron density map clearly showed molecular boundaries. Although its amino acid sequence is not known, the folding pattern of the polypeptide chain could be traced on a 2.5 A resolution electron density map. A large cleft, which is located on the molecular surface, was proved to be the active site of the enzyme by structure analyses of inhibitor-complex crystals. The highest electron density peak, which corresponds to the cleft, was assigned to a catalytically essential zinc atom on difference Fourier synthesis between native and EDTA-soaked crystals. 相似文献
57.
卡瓦胡椒及胡椒的RAPD聚类分析 总被引:2,自引:0,他引:2
目的:通过RAPD分析搞清楚卡瓦胡椒与胡椒及胡椒属其它近缘野生种的亲缘关系。方法和结果:采用随机引物80条进行筛选,用从80条随机引物中入选的20条引物,对卡瓦胡椒和胡椒属共计28份材料进行RAPD扩增,均能产生清晰的扩增谱带。重复1—2次,结果稳定可靠。20个引物共扩增出170个条带,其中多态性条带有20条,占总扩增条带数的12%。RAPD分析结果显示在相似系数0.36处对28份种质可划分为6个类型,其中卡瓦胡椒被单独聚为一类,说明卡瓦胡椒与胡椒及其它近缘野生种的亲缘关系有一定的距离。 相似文献
58.
Kai Hilpert Dirk FH Winkler Robert EW Hancock 《Biotechnology & genetic engineering reviews》2013,29(1):31-106
Spatial organization of metabolic enzymes may represent a general cellular mechanism to regulate metabolic flux. One recent example of this type of cellular phenomenon is the purinosome, a newly discovered multi-enzyme metabolic assembly that includes all of the enzymes within the de novo purine biosynthetic pathway. Our understanding of the components and regulation of purinosomes has significantly grown in recent years. This paper reviews the purine de novo biosynthesis pathway and its regulation, and presents the evidence supporting the purinosome assembly and disassembly processes under the control of G-protein-coupled receptor (GPCR) signaling. This paper also discusses the implications of purinosome and GPCR regulation in drug discovery. 相似文献
59.
Yu Pang Qiang Li Xichao Ou Hojoon Sohn Zhiying Zhang Junchen Li Hui Xia Kai Man Kam Richard J. O’Brien Junying Chi Shitong Huan Daniel P. Chin Yan-lin Zhao 《PloS one》2013,8(7)