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21.
Cloning of bacteriophage T5 promoters 总被引:3,自引:0,他引:3
Vladimir N. Ksenzenko Tatjana P. Kamynina Nina M. Pustoshilova Valentine M. Kryukov A. A. Bayev 《Molecular & general genetics : MGG》1982,185(3):520-522
Summary Bacteriophage T5 was subjected to combined hydrolysis with the restriction endonuclease PstI and HindIII and the resulting fragments were inserted into the plasmid pBR322. Selection of transformants for Aps-Tcr-phenotype made it possible to screen the hybrid plasmids that contained promoter sequences in the cloned fragments.Two PstI/HindIII fragment, 720 bp (51% of the T5 DNA length) and 1,200 bp (70%) were cloned in this study. Tcr levels for these plasmids were as high as 18 g/ml and 75 g/ml, respectively. The presence of Escherichia coli RNA polymerase binding sites on both fragments was shown using the nitrocellulose filter assay. These binding sites are situated between 35 bp and 95 bp from the HindIII cleavage site on the 1,200 bp fragment; and within 420 bp from the HindIII site on the 720 bp fragment.Abbreviations Ap
ampicillin
- Tc
tetracycline
- bp
base pairs
- NTPs
nucleoside triphosphates
- PBB
polymerase binding buffer 相似文献
22.
Randall M. Zusman M.D. Lloyd Axelrod M.D. Nina Tolkoff-Rubin M.D. 《Prostaglandins & other lipid mediators》1977,13(5):819-830
Three patients with the hepatorenal syndrome were treated with prostaglandin E1 administered through a selective renal arterial catheter. Prostaglandin E1 was given in progressively increasing doses (2 to 100 ng/kg/min) over a 60-minute period. Control plasma prostaglandin E levels were elevated in all three patients, 0.98, 0.91, and 0.83 ng/ml, respectively. At the end of the infusion, plasma prostaglandin E levels had risen to 10.4, 2.63, and 10.3 ng/ml in the three patients respectively. Plasma renin activity increased during the course of the infusion in two of the patients. The plasma aldosterone concentration did not change during the prostaglandin E1 infusion. Intrarenal prostaglandin E1 failed to increase urine volume or urinary sodium concentration in three patients with the hepatorenal syndrome. 相似文献
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25.
Vadim Danilov Nina Baranova Anvar Ismailov Nicolai Egorov 《Applied microbiology and biotechnology》1982,14(2):125-129
Summary The inhibitory effect of camphor on bioluminescence of both bacteria and bacterial luciferase has been examined. The camphor has been shown to be a substrate of cytochrome P-450 of the luminous bacteria Photobacterium fischeri. The inhibition of the luminescence reaction provided evidence for the competitive nature of the interaction of camphor and aliphatic aldehyde at the binding site for luciferase. Camphor is also supposed to interact with P-450. The findings indicate that the hydroxylation process of camphor affects the kinetics of the luminescence. 相似文献
26.
Reciprocal qualitative and quantitative immunological experiments employing an anti-Pediococcus cerevisiae aldolase serum confirmed many of the interspecific relationships demonstrated previously among lactic acid bacteria with antisera prepared against the Streptococcus faecalis fructose diphosphate aldolase. The extent of immunological relatedness observed between the Lactobacillus and Pediococcus aldolases was markedly greater than that noted between Pediococcus and Streptococcus aldolases indicating that the pediococci share closer phylogenetic ties with the rod-shaped lactobacilli than with their spherical counterparts in the streptococci. In addition to confirming the existence of definitive, but distant, relationships between the lactic acid bacteria and certain gram positive nonsporeforming anaerobes, immunological cross-reactivity was also demonstrated between the pediococcal aldolases and those of Aerococcus viridans.This paper is dedicated with deepest appreciation to Prof. Roger Y. Stanier on the occasion of his 60th birthday in token of what his friendship and guidance have meant to me. — J. L. 相似文献
27.
Mutant Chinese hamster ovarian (CHO) cells with a resistance to 7-10(-7) and 8-10(-7) M cycloheximide (CHM) were induced at mutation rates of 1.9-5.2-10(-3) and 1.6-1.8-10(-3) respectively after treatment with N-nitrosomethylurea (NMU) at 100 mug/ml. The induced mutation rates differed by two orders of magnitude from the spontaneous rate of mutation to CHM resistance. 相似文献
28.
Martin Gael Oyono Sebastien Kenmoe Ngu Njei Abanda Guy Roussel Takuissu Jean Thierry Ebogo-Belobo Raoul Kenfack-Momo Cyprien Kengne-Nde Donatien Serge Mbaga Serges Tchatchouang Josiane Kenfack-Zanguim Robertine Lontuo Fogang Elisabeth Zeukoo Menkem Juliette Laure Ndzie Ondigui Ginette Irma Kame-Ngasse Jeannette Nina Magoudjou-Pekam Arnol Bowo-Ngandji Seraphine Nkie Esemu Lucy Ndip 《PLoS neglected tropical diseases》2022,16(7)
Yellow fever (YF) has re-emerged in the last two decades causing several outbreaks in endemic countries and spreading to new receptive regions. This changing epidemiology of YF creates new challenges for global public health efforts. Yellow fever is caused by the yellow fever virus (YFV) that circulates between humans, the mosquito vector, and non-human primates (NHP). In this systematic review and meta-analysis, we review and analyse data on the case fatality rate (CFR) and prevalence of YFV in humans, and on the prevalence of YFV in arthropods, and NHP in sub-Saharan Africa (SSA). We performed a comprehensive literature search in PubMed, Web of Science, African Journal Online, and African Index Medicus databases. We included studies reporting data on the CFR and/or prevalence of YFV. Extracted data was verified and analysed using the random effect meta-analysis. We conducted subgroup, sensitivity analysis, and publication bias analyses using the random effect meta-analysis while I2 statistic was employed to determine heterogeneity. This review was registered with PROSPERO under the identification CRD42021242444. The final meta-analysis included 55 studies. The overall case fatality rate due to YFV was 31.1% (18.3–45.4) in humans and pooled prevalence of YFV infection was 9.4% (6.9–12.2) in humans. Only five studies in West and East Africa detected the YFV in mosquito species of the genus Aedes and in Anopheles funestus. In NHP, YFV antibodies were found only in members of the Cercopithecidae family. Our analysis provides evidence on the ongoing circulation of the YFV in humans, Aedes mosquitoes and NHP in SSA. These observations highlight the ongoing transmission of the YFV and its potential to cause large outbreaks in SSA. As such, strategies such as those proposed by the WHO’s Eliminate Yellow Fever Epidemics (EYE) initiative are urgently needed to control and prevent yellow fever outbreaks in SSA. 相似文献
29.
Alena Kushniarevich Larysa Sivitskaya Nina Danilenko Tadeush Novogrodskii Iosif Tsybovsky Anna Kiseleva Svetlana Kotova Gyaneshwer Chaubey Ene Metspalu Hovhannes Sahakyan Ardeshir Bahmanimehr Maere Reidla Siiri Rootsi Jüri Parik Tuuli Reisberg Alessandro Achilli Baharak Hooshiar Kashani Francesca Gandini Anna Olivieri Doron M. Behar Antonio Torroni Oleg Davydenko Richard Villems 《PloS one》2013,8(6)
Ethnic Belarusians make up more than 80% of the nine and half million people inhabiting the Republic of Belarus. Belarusians together with Ukrainians and Russians represent the East Slavic linguistic group, largest both in numbers and territory, inhabiting East Europe alongside Baltic-, Finno-Permic- and Turkic-speaking people. Till date, only a limited number of low resolution genetic studies have been performed on this population. Therefore, with the phylogeographic analysis of 565 Y-chromosomes and 267 mitochondrial DNAs from six well covered geographic sub-regions of Belarus we strove to complement the existing genetic profile of eastern Europeans. Our results reveal that around 80% of the paternal Belarusian gene pool is composed of R1a, I2a and N1c Y-chromosome haplogroups – a profile which is very similar to the two other eastern European populations – Ukrainians and Russians. The maternal Belarusian gene pool encompasses a full range of West Eurasian haplogroups and agrees well with the genetic structure of central-east European populations. Our data attest that latitudinal gradients characterize the variation of the uniparentally transmitted gene pools of modern Belarusians. In particular, the Y-chromosome reflects movements of people in central-east Europe, starting probably as early as the beginning of the Holocene. Furthermore, the matrilineal legacy of Belarusians retains two rare mitochondrial DNA haplogroups, N1a3 and N3, whose phylogeographies were explored in detail after de novo sequencing of 20 and 13 complete mitogenomes, respectively, from all over Eurasia. Our phylogeographic analyses reveal that two mitochondrial DNA lineages, N3 and N1a3, both of Middle Eastern origin, might mark distinct events of matrilineal gene flow to Europe: during the mid-Holocene period and around the Pleistocene-Holocene transition, respectively. 相似文献
30.
Jukka Kekäläinen Geir Rudolfsen Matti Janhunen Lars Figenschou Nina Peuhkuri Niina Tamper Raine Kortet 《BMC evolutionary biology》2010,10(1):20