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81.
González-Mariscal L Islas S Contreras RG García-Villegas MR Betanzos A Vega J Diaz-Quiñónez A Martín-Orozco N Ortiz-Navarrete V Cereijido M Valdés J 《Experimental cell research》1999,248(1):97-109
Most of the information on the structure and function of the tight junction (TJ) has been obtained in MDCK cells. Accordingly, we have sequenced ZO-1 in this cell type, because this protein is involved in the response of the TJ to changes in Ca2+, phosphorylation, and the cytoskeleton. ZO-1 of MDCK cells comprises 6805 bp with a predicted open reading frame of 1769 amino acids. This sequence is 92 and 87% homologous to human and mouse ZO-1, respectively. Two nuclear sorting signals located at the PDZ1 and GK domains and 17 SH3 putative binding sites at the proline-rich domain were detected. We found two new splicing regions at the proline-rich region: beta had not been reported in human and mouse counterparts, and gamma, which was previously sequenced in human and mouse ZO-1, is now identified as a splicing region. The expression of different beta and gamma isoforms varies according to the tissue tested. With the information provided by the sequence, Southern blot, and PCR experiments we can predict a single genomic copy of MDCK-ZO-1 that is at least 13.16 kb long. MDCK-ZO-1 mRNA is 7.4 kb long. Its expression is regulated by calcium, while the expression of MDCK-ZO-1 protein is not. 相似文献
82.
益生菌生物药物是指通过口服表达药用多肽(蛋白)的重组益生菌活细胞达到治疗疾病的新型口服给药系统。为了构建一种能有效防治2型糖尿病的酵母生物药物,文章首先构建了酿酒酵母(S.cerevisiae)整合型表达载体pNK1-PGK,并且通过绿色荧光蛋白(GFP)证明其表达功能正常,利用该载体将10×GLP-1 (Glucagon-like peptide-1)基因转化到酿酒酵母INVSc1中,通过营养缺陷型和Western blotting成功筛选出表达10×GLP-1的长效促胰岛素降糖酵母(Long-acting GLP-1 hypoglycemic yeast, LHY)。该酵母生长迅速,外源基因10×GLP-1表达稳定,表达量达到1.56 mg/g细胞湿重。通过链脲佐菌素和高脂高糖饮食联合诱导的方法构建了2型糖尿病小鼠模型,用LHY对其进行口服灌胃治疗,证明LHY具有较好疗效,明显降低血糖水平。 相似文献
83.
Franco Chimenti Daniela Secci Adriana Bolasco Paola Chimenti Arianna Granese Simone Carradori Elias Maccioni M. Cristina Cardia Matilde Yáñez Francisco Orallo Stefano Alcaro Francesco Ortuso Roberto Cirilli Rosella Ferretti Simona Distinto Johannes Kirchmair Thierry Langer 《Bioorganic & medicinal chemistry》2010,18(14):5063-5070
The present study reports on synthesis in high yields (70–99%), HPLC enantioseparation, inhibitory activity against human monoamino oxidases, and molecular modeling including 3D-QSAR studies, of a large series of (4-aryl-thiazol-2-yl)hydrazones (1–45). Most of the synthesized compounds proved to be potent and selective inhibitors of hMAO-B isoform in the micromolar or nanomolar range, thus demonstrating that hydrazothiazole could be considered a good pharmacophore to design new hMAO-B inhibitors. Due to the presence in some derivatives of a chiral center, we also performed a semipreparative chromatographic enantioseparation of these compounds obtained by a stereoconservative pattern. The separated enantiomers were submitted to in vitro biological evaluation to point out the stereorecognition of the active site of the enzyme towards these structures. Finally, a 3D-QSAR study was carried out using Comparative Molecular Field Analysis (CoMFA), aiming to deduce rational guidelines for the further structural modification of these lead compounds. 相似文献
84.
【目的】从培菌白蚁——黄翅大白蚁后肠微生物菌群中分离能降解几丁质的细菌。【方法】以胶体几丁质为唯一碳源,根据胶体几丁质水解透明圈的大小进行筛选。通过形态学、生理生化以及16SrRNA基因序列分析进行菌株鉴定。【结果】从黄翅大白蚁肠道中筛选到8株能够降解胶体几丁质的细菌,它们分别属于芽孢杆菌属(Bacillus)、短芽孢杆菌属(Brevibacillus)、纤维单胞菌属(Cellulomonas)、指孢囊菌属(Dactylosporangium)、黄杆菌属(Flavobacterium)、类芽孢杆菌属(Paenibacillus)、鞘氨醇单胞菌属(Sphingomonas)和寡养单胞菌属(Stenotrophomonas)。8株菌均具有几丁质酶、β-葡萄糖苷酶和内切葡聚糖酶活性。【结论】从黄翅大白蚁后肠中获得8株能够降解胶体几丁质并具有其他碳水化合物降解酶活性的细菌,这一研究为了解白蚁肠道微生物协助白蚁消化食物机制提供了依据。 相似文献
85.
In this paper some examples of the development of communities of microorganisms and plants on historic buildings and montiments
are shown. When the building stones differ from the surrounding natural substrata, an increase in the biological diversity
of the area is produced. In some cases, monuments can come to constitute a true refuge for a few species when the natural
habitat is threatened. It is suggested that biological diversity, when it does not represent a threat for the cultural heritage,
should be considered worthy of preservation. 相似文献
86.
Sergio Padilla-López María Jiménez-Hidalgo Alejandro Martín-Montalvo Catherine F. Clarke Plácido Navas Carlos Santos-Ocaña 《生物化学与生物物理学报:生物膜》2009,1788(6):1238-1248
Coenzyme Q is an isoprenylated benzoquinone lipid that functions in respiratory electron transport and as a lipid antioxidant. Dietary supplementation with Q is increasingly used as a therapeutic for treatment of mitochondrial and neurodegenerative diseases, yet little is known regarding the mechanism of its uptake. As opposed to other yeast backgrounds, EG103 strains are unable to import exogenous Q6 to the mitochondria. Furthermore, the distribution of exogenous Q6 among endomembranes suggests an impairment of the membrane traffic at the level of the endocytic pathway. This fact was confirmed after the detection of defects in the incorporation of FM4-64 marker and CPY delivery to the vacuole. A similar effect was demonstrated in double mutant strains in Q6 synthesis and several steps of endocytic process; those cells are unable to uptake exogenous Q6 to the mitochondria and restore the growth on non-fermentable carbon sources. Additional data about the positive effect of peptone presence for exogenous Q6 uptake support the hypothesis that Q6 is transported to mitochondria through an endocytic-based system. 相似文献
87.
P. Madejón L. Ciadamidaro T. Marañón J. M. Murillo 《International journal of phytoremediation》2013,15(6):602-614
Phytostabilization aims to immobilize soil contaminants using higher plants. The accumulation of trace elements in Populus alba leaves was monitored for 12 years after a mine spill. Concentrations of As and Pb significantly decreased, while concentrations of Cd and Zn did not significantly over time. Soil concentrations extracted by CaCl2 were measured by ICP-OES and results of As and Pb were below the detection limit. Long-term biomonitoring of soil contamination using poplar leaves was proven to be better suited for the study of trace elements. Plants suitable for phytostabilization must also be able to survive and reproduce in contaminated soils. Concentrations of trace elements were also measured in P. alba fruiting catkins to determine the effect on its reproduction potential. Cadmium and Zn were found to accumulate in fruiting catkins, with the transfer coefficient for Cd significantly greater than Zn. It is possible for trace elements to translocate to seed, which presents a concern for seed germination, establishment and colonization. We conclude that white poplar is a suitable tree for long-term monitoring of soil contaminated with Cd and Zn, and for phytostabilization in riparian habitats, although some caution should be taken with the possible effects on the food web.
Supplemental materials are available for this article. Go to the publisher's online edition of International Journal of Phytoremediation to view the supplemental file. 相似文献
88.
Molecular and morphological diversity of Trebouxia microalgae in sphaerothallioid Circinaria spp. lichens1 下载免费PDF全文
Arántzazu Molins Francisco J. García‐Breijo José Reig‐Armiñana Eva Barreno 《Journal of phycology》2018,54(4):494-504
Three vagrant (Circinaria hispida, Circinaria gyrosa, and Circinaria sp. ‘paramerae’) and one crustose (semi‐vagrant, Circinaria sp. ‘oromediterranea’) lichens growing in very continental areas in the Iberian Peninsula were selected to study the phycobiont diversity. Mycobiont identification was checked using nrITS DNA barcoding: Circinaria sp. ‘oromediterranea’ and Circinaria sp. ‘paramerae’ formed a new clade. Phycobiont diversity was analyzed in 50 thalli of Circinaria spp. using nrITS DNA and LSU rDNA, with microalgae coexistence being found in all the species analyzed by Sanger sequencing. The survey of phycobiont diversity showed up to four different Trebouxia spp. as the primary phycobiont in 20 thalli of C. hispida, in comparison with the remaining Circinaria spp., where only one Trebouxia was the primary microalga. In lichen species showing coexistence, some complementary approaches are needed (454 pyrosequencing and/or ultrastructural analyses). Five specimens were selected for high‐throughput screening (HTS) analyses: 22 Trebouxia OTUs were detected, 10 of them not previously known. TEM analyses showed three different cell morphotypes (Trebouxia sp. OTU A12, OTU S51, and T. cretacea) whose ultrastructure is described here in detail for the first time. HTS revealed a different microalgae pool in each species studied, and we cannot assume a specific pattern between these pools and the ecological and/or morphological characteristics. The mechanisms involved in the selection of the primary phycobiont and the other microalgae by the mycobiont are unknown, and require complex experimental designs. The systematics of the genus Circinaria is not yet well resolved, and more analyses are needed to establish a precise delimitation of the species. 相似文献
89.
90.
Jian Xiao Xiaoyan Zhu Bin He Yufeng Zhang Bo Kang Zhinong Wang Xin Ni 《Journal of biomedical science》2011,18(1):35