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1.
Hardies SC; Martin SL; Voliva CF; Hutchison CA d; Edgell MH 《Molecular biology and evolution》1986,3(2):109-125
2.
Summary Microsomal and soluble fractions of Pleurotus pulmonarius exhibited a reduced carbon monoxide difference spectrum with P450 maxima at 448nm and 450–452nm respectively. Substrate induced Type I spectra were observed on addition of benzo(a)pyrene to both fractions. Benzo(a)pyrene hydroxylation was measured using the aryl hydrocarbon hydroxylase assay and was observed to be P450 dependent as indicated by carbon monoxide inhibition together with the substrate binding characteristics. The activity of the fractions were observed to give Km of 200mM and 660mM and Vmax of 1.25 nmol/min/nmol P450 and 0.57 nmol/min/nmol P450 for the microsomal and cytosolic fractions respectively. 相似文献
3.
Yan Lu Shulin/SL Li Shiguo/SG Zhu Yabin/YB Gong Jun/J Shi Ling/ L Xu 《Biological procedures online》2017,19(1):2
DNA/RNA methylation plays an important role in lung cancer initiation and progression. Liquid biopsy makes use of cells, nucleotides and proteins released from tumor cells into body fluids to help with cancer diagnosis and prognosis. Methylation of circulating tumor DNA (ctDNA) has gained increasing attention as biomarkers for lung cancer. Here we briefly introduce the biological basis and detection method of ctDNA methylation, and review various applications of methylated DNA in body fluids in lung cancer screening, diagnosis, prognosis, monitoring and treatment prediction. We also discuss the emerging role of RNA methylation as biomarkers for cancer. 相似文献
4.
Grogan G Roberts GA Bougioukou D Turner NJ Flitsch SL 《The Journal of biological chemistry》2001,276(16):12565-12572
The enzyme 6-oxocamphor hydrolase, which catalyzes the desymmetrization of 6-oxocamphor to yield (2R,4S)-alpha-campholinic acid, has been purified with a factor of 35.7 from a wild type strain of Rhodococcus sp. NCIMB 9784 grown on (1R)-(+)-camphor as the sole carbon source. The enzyme has a subunit molecular mass of 28,488 Da by electrospray mass spectrometry and a native molecular mass of approximately 83,000 Da indicating that the active protein is trimeric. The specific activity was determined to be 357.5 units mg(-)1, and the K(m) was determined to be 0.05 mm for the natural substrate. The N-terminal amino acid sequence was obtained from the purified protein, and using this information, the gene encoding the enzyme was cloned. The translation of the gene was found to bear significant homology to the crotonase superfamily of enzymes. The gene is closely associated with an open reading frame encoding a ferredoxin reductase that may be involved in the initial step in the biodegradation of camphor. A mechanism for 6-oxocamphor hydrolase based on sequence homology and the known mechanism of the crotonase enzymes is proposed. 相似文献
5.
Lellouch AC Watt GM Geremia RA Flitsch SL 《Biochemical and biophysical research communications》2000,272(1):290-292
The biochemical characterization of bacterial glycosyltransferases involved in the assembly of cell-wall-associated polysaccharides is often hindered by the lack of the appropriate undecaprenyl-pyrophosphate-linked acceptor substrate. In order to find a suitable synthetic substrate for the alpha1,3-mannosyltransferase AceA from Acetobacter xylinum, phytanyl-pyrophosphate-linked cellobiose was prepared. In the presence of GDP-[14C]mannose and recombinant AceA, the phytanyl-pyrophosphate-linked cellobiose afforded a 14C-labeled trisaccharide that was sensitive to alpha-mannosidase degradation in a fashion analogous to the natural undecaprenyl-pyrophosphate-linked cellobiose substrate. These results suggest that phytanyl-pyrophosphate-linked oligosaccharides may be useful substrates for other important bacterial glycosyltransferases. 相似文献
6.
Out of Africa and back again: nested cladistic analysis of human Y chromosome variation 总被引:18,自引:3,他引:15
Hammer MF; Karafet T; Rasanayagam A; Wood ET; Altheide TK; Jenkins T; Griffiths RC; Templeton AR; Zegura SL 《Molecular biology and evolution》1998,15(4):427-441
We surveyed nine diallelic polymorphic sites on the Y chromosomes of 1,544
individuals from Africa, Asia, Europe, Oceania, and the New World.
Phylogenetic analyses of these nine sites resulted in a tree for 10
distinct Y haplotypes with a coalescence time of approximately 150,000
years. The 10 haplotypes were unevenly distributed among human populations:
5 were restricted to a particular continent, 2 were shared between Africa
and Europe, 1 was present only in the Old World, and 2 were found in all
geographic regions surveyed. The ancestral haplotype was limited to African
populations. Random permutation procedures revealed statistically
significant patterns of geographical structuring of this paternal genetic
variation. The results of a nested cladistic analysis indicated that these
geographical associations arose through a combination of processes,
including restricted, recurrent gene flow (isolation by distance) and range
expansions. We inferred that one of the oldest events in the nested
cladistic analysis was a range expansion out of Africa which resulted in
the complete replacement of Y chromosomes throughout the Old World, a
finding consistent with many versions of the Out of Africa Replacement
Model. A second and more recent range expansion brought Asian Y chromosomes
back to Africa without replacing the indigenous African male gene pool.
Thus, the previously observed high levels of Y chromosomal genetic
diversity in Africa may be due in part to bidirectional population
movements. Finally, a comparison of our results with those from nested
cladistic analyses of human mtDNA and beta-globin data revealed different
patterns of inferences for males and females concerning the relative roles
of population history (range expansions) and population structure
(recurrent gene flow), thereby adding a new sex-specific component to
models of human evolution.
相似文献
7.
JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献8.
9.
Inhibition of protein translocation at the endoplasmic reticulum promotes activation of the unfolded protein response 总被引:1,自引:0,他引:1
McKibbin C Mares A Piacenti M Williams H Roboti P Puumalainen M Callan AC Lesiak-Mieczkowska K Linder S Harant H High S Flitsch SL Whitehead RC Swanton E 《The Biochemical journal》2012,442(3):639-648
Selective small-molecule inhibitors represent powerful tools for the dissection of complex biological processes. ES(I) (eeyarestatin I) is a novel modulator of ER (endoplasmic reticulum) function. In the present study, we show that in addition to acutely inhibiting ERAD (ER-associated degradation), ES(I) causes production of mislocalized polypeptides that are ubiquitinated and degraded. Unexpectedly, our results suggest that these non-translocated polypeptides promote activation of the UPR (unfolded protein response), and indeed we can recapitulate UPR activation with an alternative and quite distinct inhibitor of ER translocation. These results suggest that the accumulation of non-translocated proteins in the cytosol may represent a novel mechanism that contributes to UPR activation. 相似文献
10.
Mire Convery Caitríona Dennis Sin Rowsell Andreas Engel J Bernard Heymann Gary Parkinson Rob Russell Gianfranco Gilardi Richard Newman Irmgard Sinning Sabine Flitsch Philip AS Lowden Steve Matthews Gerard J Kleywegt Jon D Stewart 《Current opinion in structural biology》1999,9(6):653
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in structural biology. 相似文献