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排序方式: 共有619条查询结果,搜索用时 15 毫秒
611.
Maureen McKeague Erin M. McConnell Jose Cruz-Toledo Elyse D. Bernard Amanda Pach Emily Mastronardi Xueru Zhang Michael Beking Tariq Francis Amanda Giamberardino Ashley Cabecinha Annamaria Ruscito Rocio Aranda-Rodriguez Michel Dumontier Maria C. DeRosa 《Journal of molecular evolution》2015,81(5-6):150-161
612.
Annamaria Merico Silvia Galafassi Jure Pikur & Concetta Compagno 《FEMS yeast research》2009,9(5):749-756
Yeasts belonging to the lineage that underwent whole-genome duplication (WGD) possess a good fermentative potential and can proliferate in the absence of oxygen. In this study, we analyzed the pre-WGD yeast Kluyveromyces lactis and its ability to grow under oxygen-limited conditions. Under these conditions, K. lactis starts to increase the glucose metabolism and accumulates ethanol and glycerol. However, under more limited conditions, the fermentative metabolism decreases, causing a slow growth rate. In contrast, Saccharomyces cerevisiae and Saccharomyces kluyveri in anaerobiosis exhibit almost the same growth rate as in aerobiosis. In this work, we showed that in K. lactis , under oxygen-limited conditions, a decreased expression of RAG1 occurred. The activity of glucose-6-phosphate dehydrogenase also decreased, likely causing a reduced flux in the pentose phosphate pathway. Comparison of related and characterized yeasts suggests that the behavior observed in K. lactis could reflect the lack of an efficient mechanism to maintain a high glycolytic flux and to balance the redox homeostasis under hypoxic conditions. This could be a consequence of a recent specialization of K. lactis toward living in a niche where the ethanol accumulation at high oxygen concentrations and the ability to survive at a low oxygen concentration do not represent an advantage. 相似文献
613.
Complementation Test between Alkaline Phosphatase Regulatory Mutations phoB and phoRc in ESCHERICHIA COLI 下载免费PDF全文
A phoRc and a phoB mutation belong to the same complementation group suggesting that there is a single positive control gene for alkaline phosphatase synthesis. 相似文献
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615.
The in vitro 7α-dehydroxylation of cholic and chenodeoxycholic acids by mixed cultures of mouse cecal microorganisms was studied.
Conventional anaerobic techniques and rigorous oxygen-free anaerobic experimental conditions were compared. It was found that
the total number of anaerobic oxygen-intolerant microorganisms was about 10 times higher than that of anaerobic microorganisms
that tolerate oxygen. Among the anaerobic 7α-dehydroxylating microorganisms, the oxygen-intolerant ones are about 1,000 to
10,000 times more numerous than the oxygen-tolerant ones. It can be concluded that the 7α-dehydroxylating activity is more
common among oxygenintolerant than oxygen-tolerant anaerobic microorganisms. 相似文献
616.
Angela Rizzo Carmen Maresca Carmen D'Angelo Manuela Porru Serena Di Vito Erica Salvati Andrea Sacconi Francesco Berardinelli Antonella Sgura Sergey Kuznetsov Swapnil Potdar Antti Hassinen Antonella Stoppacciaro Pasquale Zizza Annamaria Biroccio 《Aging cell》2023,22(11):e13944
Drug repositioning strategy represents a valid tool to accelerate the pharmacological development through the identification of new applications for already existing compounds. In this view, we aimed at discovering molecules able to trigger telomere-localized DNA damage and tumor cell death. By applying an automated high-content spinning-disk microscopy, we performed a screening aimed at identifying, on a library of 527 drugs, molecules able to negatively affect the expression of TRF2, a key protein in telomere maintenance. FK866, resulting from the screening as the best candidate hit, was then validated at biochemical and molecular levels and the mechanism underlying its activity in telomere deprotection was elucidated both in vitro and in vivo. The results of this study allow us to discover a novel role of FK866 in promoting, through the production of reactive oxygen species, telomere loss and deprotection, two events leading to an accumulation of DNA damage and tumor cell death. The ability of FK866 to induce telomere damage and apoptosis was also demonstrated in advanced preclinical models evidencing the antitumoral activity of FK866 in triple-negative breast cancer—a particularly aggressive breast cancer subtype still orphan of targeted therapies and characterized by high expression levels of both NAMPT and TRF2. Overall, our findings pave the way to the development of novel anticancer strategies to counteract triple-negative breast cancer, based on the use of telomere deprotecting agents, including NAMPT inhibitors, that would rapidly progress from bench to bedside. 相似文献
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619.
Carmelina Magnani Laura Cremonesi Annamaria Giunta Paola Magnaghi Roberto Taramelli Maurizio Ferrari 《Human genetics》1996,98(1):102-108
In the cystic fibrosis conductance transmembrane regulator (CFTR) gene a few small deletions and only a large, complex, 50-kb
deletion have been described so far. We report a second large deletion, which had been hypothesized in a patient affected
by cystic fibrosis on the basis of an abnormal pattern of inheritance of the intragenic microsatellites IVS17b/TA and IVS17b/CA.
Southern blot analysis revealed the presence of an anomalous band in the patient and her father, in the region encompassing
exons 13 – 19, approximately 0.6 kb shorten than the one present in normal controls, in addition to the band of the correct
size. Cloning and sequencing the DNA fragments spanning the region of interest demonstrated the presence of a 703-bp deletion
causing complete removal of exon 17b in the paternal cystic fibrosis chromosome. This analysis revealed the presence of two
short direct repeats flanking the breakpoints. The 3′ repeat partially overlapped the IVS17b/CA microsatellite and the number
of CA repeated units present in the paternal cystic fibrosis allele was the shortest ever found among chromosomes so far analyzed.
These data may suggest that the mechanism for the generation of the deletion may have involved a slipped mispairing during
DNA replication, which has not previously been described in the CFTR gene.
Received: 27 December 1995 / Accepted: 30 January 1996 相似文献