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1.
C T Lago G Sannia G Marino C H Squires J M Calvo M De Felice 《Biochimica et biophysica acta》1985,824(1):74-79
The ilvI and ilvH gene products were identified physically by electrophoretic analysis of in vivo-labelled polypeptides produced in minicells from plasmids carrying the wild-type ilvIH operon of Escherichia coli K-12 and derivatives of it. An analysis of the distribution of methionine residues in the amino-terminal portion of micro-quantities of the ilvI product eluted from gel showed that the translational start of the ilvI gene is the promoter-proximal one of three putative methionine codons predicted from the DNA sequence. 相似文献
2.
Alternate Requirement for Vitamin B12 or Methionine in Mutants of Pseudomonas denitrificans, a Vitamin B12-producing Bacterium 总被引:4,自引:2,他引:2 下载免费PDF全文
Experiments are described which indicate that Pseudomonas denitrificans, an organism that overproduces vitamin B(12), uses the B(12) pathway exclusively for methionine synthesis. 相似文献
3.
G. Liguori L. De Gregorio M. Tucci C. T. Lago A. Barra T. A. Dragani M. Persico 《Mammalian genome》1997,8(7):502-505
Teratocarcinoma-derived growth factor-1 (Tdgf1), a member of the ``EGF family' of growth factors, is expressed during mouse gastrulation in the forming mesoderm and later
in the truncus arteriosus of the developing heart. In humans, TDGF1 is highly expressed in germ cell tumors and in colon and
mammary carcinomas. In mouse, one gene (Tdgf1) and two pseudogenes (Tdgf1-ps1 and Tdgf1-ps2) have been isolated and characterized. Tdgf1 corresponds to the gene expressed in F9 teratocarcinoma cells. Tdgf1-ps1 and Tdgf1-ps2 are two intronless sequences with all the characteristics of retroposons. In the present paper, we assign the chromosomal
location for Tdgf1, Tdgf1-ps1, and Tdgf1-ps2 sequences to Chromosomes (Chrs) 9, 16, and 17, respectively. Two previously described mouse mutants, scant hair (sch) and fur deficient (fd), map near the Tdgf1 gene. Analysis of their DNA coding region provided no evidence that Tdgf1 could be the responsible gene for these phenotypes. Finally, analysis of the DNA from several Mus musculus strains and from Mus spretus mice revealed a highly variable restriction pattern and the absence of the Tdgf1-ps1 genomic sequence from the Mus spretus genome.
Received: 23 November 1996 / Accepted: 17 February 1997 相似文献
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Henrique Barbosa Thais A. Costa-Silva Geanne A. Alves Conserva Adelson J. Araujo Ana Luísa L. Lordello Guilherme M. Antar Maiara Amaral Marisi G. Soares Andre G. Tempone João Henrique G. Lago 《化学与生物多样性》2021,18(4):e2001022
One new aporphine, dicentrine-β-N-oxide ( 1 ), together with five related known alkaloids dehydrodicentrine ( 2 ), predicentrine ( 3 ), N-methyllaurotetanine ( 4 ), cassythicine ( 5 ), and dicentrine ( 6 ) were isolated from the leaves of Ocotea puberula (Lauraceae). Antiprotozoal activity of the isolated compounds was evaluated in vitro against trypomastigote forms of Trypanosoma cruzi. Among the tested compounds, alkaloid 1 exhibited higher potential with EC50 value of 18.2 μM and reduced toxicity against NCTC cells (CC50>200 μM – SI>11.0), similar to positive control benznidazole (EC50 of 17.7 μM and SI=10.7). Considering the promising results of dicentrine-β-N-oxide ( 1 ) against trypomastigotes, the mechanism of parasite death caused by this alkaloid was investigated. As observed, this compound reached the plasma membrane electric potential directly after 2 h of incubation and triggered mitochondrial depolarization, which probably leads to trypomastigote death. Therefore, dicentrine-β-N-oxide ( 1 ), reported for the first time in this work, can contribute to future works for the development of new trypanocidal agents. 相似文献
6.
Lago Jennifer L. Burcar Bradley T. Hud Nicholas V. Febrian Rio Mehta Christopher Bracher Paul J. Atlas Zachary D. Pasek Matthew A. 《Origins of life and evolution of the biosphere》2020,50(1-2):1-14
Origins of Life and Evolution of Biospheres - The numerous and varied roles of phosphorylated organic molecules in biochemistry suggest they may have been important to the origin of life. The... 相似文献
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Molecular dynamics simulations of linear models interacting through a dipolar Kihara intermolecular potential are presented. Molecular orientation correlations are used to calculate the orientational factor kappa squared in the resonance energy transfer (RET) as a function of the intermolecular separation. The distance, R 0 (2/3), at which the simulated systems show an isotropic behavior is calculated and an analysis of the dependence of R 0 (2/3) on microscopic properties (molecular aspect ratio and dipole moment) as well on thermodynamics (temperature and density) is presented. An explanation of the use of metallic cations as probes in RET is given and some relations of our models with biological molecules are pointed out. 相似文献
9.
Regina Maria Barbosa Cristiane da Silva Cabral Tania di Giacomo do Lago Adriana de Araujo Pinho 《PloS one》2016,11(11)
BackgroundIn many countries, young women of reproductive age have been especially affected by the HIV epidemic, which have fostered research to better understand how HIV infection influences and shapes women´s fertility and reproductive and sexual decisions. In Brazil, few studies have focused on the impact of the HIV epidemic on contraceptive choices among women living with HIV (WLHIV).ObjectiveThis study evaluates the impact HIV infection may have in the access to female sterilization in Brazil, using a time-to-event analysis.MethodsA cross-sectional quantitative study (GENIH study) was conducted between February 2013 and April 2014 in the city of São Paulo, comparing two probabilistic samples of 975 WLHIV and 1,003 women not living with HIV (WNLHIV) aged 18 to 49. Sexual and reproductive data was collected retrospectively in order to reconstruct women''s reproductive trajectories. Given the objectives of this study, the analysis was restricted to women with parity one or more and, in case of WLHIV, to those sterilized after HIV diagnosis and not infected through vertical transmission. The final sample analysis included 683 WNLHIV and 690 WLHIV. A series of multivariable-adjusted Cox models estimated the probability of being sterilized after HIV diagnosis, compared with WNLHIV. Models were adjusted for schooling, race/color, and stratified by parity at last delivery (1–2, 3+). Hazard ratios were calculated for female sterilization, and separately for interval and postpartum procedures (performed in conjunction with caesarean section or immediately after vaginal delivery). Additionally, information regarding unmet demand for female sterilization was also explored.FindingsNo statistical difference in the overall risk of sterilization between WLHIV and WNLHIV in the two parity-related groups is observed: HR = 0.88 (0.54–1.43) and 0.94 (0.69–1.29), respectively, among women with 1–2 children and those with three and more. However, significant differences regarding the impact of HIV infection at sterilization are observed depending on the timing and the type of sterilization procedure. The probability of obtaining an interval sterilization is significantly lower for WLHIV compared to those not living with HIV. The reverse occurs regarding postpartum sterilization. Although sterilization is mainly performed in conjunction with caesarean section in Brazil, it is evident that caesarean sections are not the sole factor increasing the risk of sterilization among WLHIV.ConclusionThe results indicate barriers in the access to services offering interval sterilization for WLHIV and certain facilitation in obtaining the procedure in conjunction with caesarean section. Health policy makers at local and national levels should promote institutional changes in order to facilitate access to interval sterilization and to confront the sensitive discussion of WLHIV’s eligibility for postpartum sterilization. It is also urgent to increase access to a wider range of contraceptive methods for WLHIV and promote dual method protection strategies. Moreover, since condom use may decrease in the future in the context of the preventive effect of antiretroviral therapy, promoting dual methods will expand the choices regarding the reproductive rights of women living with HIV. 相似文献
10.
Svio S. Costa Leticia A. B. Lago Artur Silva Diego A. das Graas Jernimo Lameira Rafael A. Baraúna 《Genetics and molecular biology》2022,45(1)
Bacteriocins are antimicrobial peptides expressed by bacteria through ribosomal activity. In this study, we analyzed the diversity of bacteriocin-like genes in the Tucuruí-HPP using a whole-metagenome shotgun sequencing approach. Three layers of the water column were analyzed (photic, aphotic and sediment). Detection of bacteriocin-like genes was performed with blastx using the BAGEL4 database as subject sequences. In order to calculate the abundance of bacteriocin-like genes we also determined the number of 16S rRNA genes using blastn. Taxonomic analysis was performed using RAST server and the metagenome was assembled using IDBA-UD in order to recover the full sequence of a zoocin which had its three-dimensional structure determined. The photic zone presented the highest number of reads affiliated to bacteriocins. The most abundant bacteriocins were sonorensin, Klebicin D , pyocin and colicin. The zoocin model was composed of eight anti-parallel β-sheets and two α-helices with a Zn2+ ion in the active site. This model was considerably stable during 10 ns of molecular dynamics simulation. We observed a high diversity of bacteriocins in the Tucuruí-HPP, demonstrating that the environment is an inexhaustible source for prospecting these molecules. Finally, the zoocin model can be used for further studies of substrate binding and molecular mechanisms involving peptidoglycan degradation. 相似文献