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81.
《Bioscience, biotechnology, and biochemistry》2013,77(11):1960-1961
FI-CMCase cDNA of Aspergillus aculeatus was expressed in Escherichia coli by using the tac promoter of E. coli. Transformants of E. coli harboring a plasmid pHEM06 containing mature form FI-CMCase cDNA produced FI-CMCase in the cytoplasm of the cells. The enzyme from E. coli cells was purified to yield 56% and it was immunological identical to that of FI-CMCase purified from A. aculeatus. 相似文献
82.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):649-656
Direct interaction between 7-chloro-1-cyclopropyl-6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid and primary α-amino acids (exemplified by glycine, alanine, and l-valine) in aqueous ethanolic NaHCO3 at 70–80°C for 24–72?h produced the respective N-(4-oxoquinolin-7-yl)-α-amino acids (6a–c). The latter derivatives underwent reductive lactamization upon treatment with Na2S2O4 in aqueous ethanol to afford moderate yields of the corresponding pyrido[2,3-f]quinoxaline-8-carboxylic acids (8a–c). Acetylation of 8a–c using acetyl chloride afforded N4-acetylated hexahydro-2,7-dioxopyrido[2,3-f]quinoxaline-8-carboxylic acids (9a–c). The structures, assigned to these new heterocyclic products, are supported by analytical and spectral data. The synthesized compounds (6a–c/9a–c) showed appreciable antibacterial activity as compared with ciprofloxacin. 相似文献
83.
DNA damage created by endogenous or exogenous genotoxic agents can exist in multiple forms, and if allowed to persist, can promote genome instability and directly lead to various human diseases, particularly cancer, neurological abnormalities, immunodeficiency and premature aging. To avoid such deleterious outcomes, cells have evolved an array of DNA repair pathways, which carry out what is typically a multiple-step process to resolve specific DNA lesions and maintain genome integrity. To fully appreciate the biological contributions of the different DNA repair systems, one must keep in mind the cellular context within which they operate. For example, the human body is composed of non-dividing and dividing cell types, including, in the brain, neurons and glial cells. We describe herein the molecular mechanisms of the different DNA repair pathways, and review their roles in non-dividing and dividing cells, with an eye toward how these pathways may regulate the development of neurological disease. 相似文献
84.
具有内含子的大鳞副泥鳅Sox8基因(英文) 总被引:3,自引:0,他引:3
鱼类在脊椎动物系统进化过程中起着承先启后的作用,其性别决定具有原始性、多样性和可塑性。深入研究鱼类的性别决定和分化具有重大的理论意义。Sox基因家族是九十年代发现的一个新的基因家族,其中的许多成员都与性别决定和分化具有直接的关系。大鳞副泥鳅是一种常见的小型鱼类,属于鲤形目鳅科,是少数具有异形性染色体中的一种。本文根据已发表的Sox蛋白质的序列资料,选择在不同物种中保守程度最高的区段设计兼并引物。该组引物可以特异扩增 Sox基因的 HMG盒区。以大鳞副泥鳅基因组 DNA为模板,在扩增产物中有三条主带,其大小分别为220bp,550bp和1500bp,另有一条相当弱的带,大小为700bp(Fig.1)。雌雄个体中扩增结果一致。经克隆和DNA序列分析,从550bp扩增带中得到一新的基因片段,长500bp,编码53个氨基酸;其余部分长340bp,可能为一内含子,且符合“GT…AG”规律(Fig.2)。其可能编码的蛋白质氨基酸序列与小鼠的 Sox8, 9, 10,SRY基因的相似性分别为 96%, 94%, 90%和 47%;与人类 Sox 8, 9, 10, SRY基因的相似性分别为64%, 94%, 58%和40%(Fig.3)。 相似文献
85.
86.
Hashemi M Eskandari-Nasab E Fazaeli A Rezaei H Mashhadi MA Arbabi F Taheri M 《Gene》2012,505(1):176-179
Caspase-8 (CASP8) plays a critical role in regulating apoptosis, and its functional polymorphisms may modify cancer risk. We investigated the possible association between CASP8 -652 6N ins/del (rs3834129) and the risk of breast cancer in a sample of Iranian population. This case-control study was done on 236 breast cancer patients and 203 cancer free healthy female. We designed a rapid and simple bi-directional PCR allele-specific amplification (bi-PASA) for detection of CASP8 -652 6N ins/del polymorphism. The results showed that the CASP8 -652 6N del/dl genotype was inversely associated with breast cancer risk (OR=0.33, 95% CI=0.17-0.65, p=0.001). The frequencies of the del allele in cases and controls were 29.1% and 38.6%, respectively. An inverse association between CASP8 6N del variant and the risk of breast cancer (OR=0.66, 95% CI=0.66-0.87, p=0.002) was found. In conclusion, the result suggests that the CASP8 -652 6N del polymorphism plays a protective role in susceptibility to breast cancer in our population. Further studies in other populations with larger samples are needed to confirm these findings. 相似文献
87.
John M. C. Gutteridge Melinda West Kent Eneff Robert A. Floyd 《Free radical research》1990,10(3):159-165
Bleomycin, in the presence of ferric salts, oxygen and a suitable reductant, degrades DNA with the release of base propenals, detected as thiobarbituric acid (TBA) reactivity, and the formation of 8-hydroxydeo-xyguanosine (80HdG) detected by HPLC. When xanthine oxidase is added to the incubated mixture of DNA degradation products, TBA-reactivity is destroyed but 80HdG formation is increased. EPR Spin trapping experiments show that hydroxyl radicals (OH) are formed in the reaction mixture and can be inhibited by the inclusion of either superoxide dismutase or catalase. These findings suggest that the base propenals and possibly malondialdehyde, formed from them, are aldehydic substrates for xanthine oxidase and, the product of this reaction is superoxide (O2-) and hydrogen peroxide (H2O2). Thus, TBA reactivity is destroyed in the formation of O2- and H2O2 which stimulate further oxidative damage to DNA resulting in increased 8OHdG formation. 相似文献
88.
为探讨八肽胆囊收缩素(CCk-8)和阿片肽相互作用的分子机理,利用抗体免疫沉淀技术研究了CCK-8与NDAP(k阿片受体激动剂)对大鼠脑(去皮层和小脑)和脊髓背柱组织Fos蛋白的影响。结果表明,0.1μmol/LCCK-8可显著刺激脑和脊髓组织中Fos蛋白增加(分别是对照组的3.8倍和3.6倍)。相同浓度的NDAP对Fos蛋白的生成亦有一定的诱导作用,分别是对照组的2.7倍和2.6倍。CCK-8和NDAP共同处理组织,Fos蛋白生成水平相似(脑)或高于(脊髓)CCK~-8单独诱导的水平。结果表明,CCK-8和NDAP均可直接诱导大鼠脑和脊髓组织c-fos的表达,它们对c-fos表达的相互作用在脑和脊髓中呈现不同的模式。 相似文献
89.
Differentiated inhibition of DNA, RNA and protein synthesis in L1210 cells by 8-methoxypsoralen 总被引:1,自引:0,他引:1
The synthesis of DNA, RNA and protein was measured in L1210 cells following treatment with 8-methoxypsoralen in combination with long wavelength ultraviolet irradiation. The results show that the DNA synthesis is strongly inhibited (approximately 95%) at 200 ng/ml reaching a minimum within 2 hours while RNA synthesis is only weakly affected at this concentration (approximately 40% inhibition). At 2 micrograms/ml the RNA synthesis is inhibited approximately 90%. Even at this concentration only a moderate effect is seen on the protein synthesis. These results strongly indicate that the phototoxic action of 8-methoxypsoralen is primarily due to inhibition of DNA synthesis. 相似文献
90.
Andrea E. Rodríguez Camila López-Crisosto Daniel Peña-Oyarzún Daniela Salas Valentina Parra Clara Quiroga 《Autophagy》2016,12(2):287-296
Autophagy is mainly regulated by post-translational and lipid modifications of ATG proteins. In some scenarios, the induction of autophagy is accompanied by increased levels of certain ATG mRNAs such as MAP1LC3B/LC3B, ATG5 or ATG12. However, little is known about the regulation of ATG protein synthesis at the translational level. The cochaperone of the HSP70 system BAG3 (BCL2-associated athanogene 3) has been associated to LC3B lipidation through an unknown mechanism. In the present work, we studied how BAG3 controls autophagy in HeLa and HEK293 cells. Our results showed that BAG3 regulates the basal amount of total cellular LC3B protein by controlling its mRNA translation. This effect was apparently specific to LC3B because other ATG protein levels were not affected. BAG3 knockdown did not affect LC3B lipidation induced by nutrient deprivation or proteasome inhibition. We concluded that BAG3 maintains the basal amount of LC3B protein by controlling the translation of its mRNA in HeLa and HEK293 cells. 相似文献