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131.
132.
K.L. Chew S. Octavia R. Jureen R.T.P. Lin J.W.P. Teo 《Letters in applied microbiology》2021,73(3):286-293
The objective of the study was to evaluate the use of targeted multiplex Nanopore MinION amplicon re-sequencing of key Candida spp. from blood culture bottles to identify azole and echinocandin resistance associated SNPs. Targeted PCR amplification of azole (ERG11 and ERG3) and echinocandin (FKS) resistance-associated loci was performed on positive blood culture media. Sequencing was performed using MinION nanopore device with R9.4.1 Flow Cells. Twenty-eight spiked blood cultures (ATCC strains and clinical isolates) and 12 prospectively collected positive blood cultures with candidaemia were included. Isolate species included Candida albicans, Candida glabrata, Candida krusei, Candida parapsilosis, Candida tropicalis and Candida auris. SNPs that were identified on ERG and FKS genes using Snippy tool and CLC Genomic Workbench were correlated with phenotypic testing by broth microdilution (YeastOne™ Sensititre). Illumina whole-genome-sequencing and Sanger-sequencing were also performed as confirmatory testing of the mutations identified from nanopore sequencing data. There was a perfect agreement of the resistance-associated mutations detected by MinION-nanopore-sequencing compared to phenotypic testing for acquired resistance (16 with azole resistance; 3 with echinocandin resistance), and perfect concordance of the nanopore sequence mutations to Illumina and Sanger data. Mutations with no known association with phenotypic drug resistance and novel mutations were also detected. 相似文献
133.
Peng Wang Ronghua Luo Min Zhang Yaqing Wang Tianzhang Song Tingting Tao Zhongyu Li Lin Jin Hongyi Zheng Wenwen Chen Mengqian Zhao Yongtang Zheng Jianhua Qin 《Cell death & disease》2020,11(12)
COVID-19, caused by SARS-CoV-2, is an acute and rapidly developing pandemic, which leads to a global health crisis. SARS-CoV-2 primarily attacks human alveoli and causes severe lung infection and damage. To better understand the molecular basis of this disease, we sought to characterize the responses of alveolar epithelium and its adjacent microvascular endothelium to viral infection under a co-culture system. SARS-CoV-2 infection caused massive virus replication and dramatic organelles remodeling in alveolar epithelial cells, alone. While, viral infection affected endothelial cells in an indirect manner, which was mediated by infected alveolar epithelium. Proteomics analysis and TEM examinations showed viral infection caused global proteomic modulations and marked ultrastructural changes in both epithelial cells and endothelial cells under the co-culture system. In particular, viral infection elicited global protein changes and structural reorganizations across many sub-cellular compartments in epithelial cells. Among the affected organelles, mitochondrion seems to be a primary target organelle. Besides, according to EM and proteomic results, we identified Daurisoline, a potent autophagy inhibitor, could inhibit virus replication effectively in host cells. Collectively, our study revealed an unrecognized cross-talk between epithelium and endothelium, which contributed to alveolar–capillary injury during SARS-CoV-2 infection. These new findings will expand our understanding of COVID-19 and may also be helpful for targeted drug development.Subject terms: Mechanisms of disease, Viral infection 相似文献
134.
New mutation affecting the synthesis of some membrane proteins and sporulation in Bacillus subtilis. 总被引:2,自引:1,他引:1
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A new mutation, mpo, which affects the synthesis of some membrane proteins and sporulation in Bacillus subtilis was identified. The mpo mutation was tightly linked to the overproduction of membrane proteins MP32 and MP18 (molecular weights of 32,000 and 18,000, respectively) and the temperature-sensitive sporulation phenotype. Genetic analysis showed that the mpo mutation maps between the spoIIIB and lys loci. 相似文献
135.
Radiation inactivation target size of rat adipocyte glucose transporters in the plasma membrane and intracellular pools 总被引:1,自引:0,他引:1
D B Jacobs C J Berenski R A Spangler C Y Jung 《The Journal of biological chemistry》1987,262(17):8084-8087
The in situ assembly states of the glucose transport carrier protein in the plasma membrane and in the intracellular (microsomal) storage pool of rat adipocytes were assessed by studying radiation-induced inactivation of the D-glucose-sensitive cytochalasin B binding activities. High energy radiation inactivated the glucose-sensitive cytochalasin B binding of each of these membrane preparations by reducing the total number of the binding sites without affecting the dissociation constant. The reduction in total number of binding sites was analyzed as a function of radiation dose based on target theory, from which a radiation-sensitive mass (target size) was calculated. When the plasma membranes of insulin-treated adipocytes were used, a target size of approximately 58,000 daltons was obtained. For adipocyte microsomal membranes, we obtained target sizes of approximately 112,000 and 109,000 daltons prior to and after insulin treatment, respectively. In the case of microsomal membranes, however, inactivation data showed anomalously low radiation sensitivities at low radiation doses, which may be interpreted as indicating the presence of a radiation-sensitive inhibitor. These results suggest that the adipocyte glucose transporter occurs as a monomer in the plasma membrane while existing in the intracellular reserve pool either as a homodimer or as a stoichiometric complex with a protein of an approximately equal size. 相似文献
136.
137.
C K?nig Y L Yan J Postlethwait S Wendler J A Campos-Ortega 《Mechanisms of development》1999,86(1-2):17-28
We describe the characterization of the zebrafish homologue of the human gene DLG3. The zebrafish dlg3 gene encodes a membrane-associated guanylate kinase containing a single PDZ domain. This gene was cloned using a gene-trap construct inserted in the gene's first intron. The insertion co-segregates with a viable mutation called humpback (hmp), which leads to formation of ankylotic vertebrae in adult fishes. Insertion and mutation have both been mapped to chromosome 12, in a segment which is syntenic with region p12 to q12 of human chromosome 17. The hmp mutant phenotype, however, appears to be due to two point mutations in the guanylate kinase domain rather than to the transgene insertion itself. The results of this study are discussed in the light of the possible function of the guanylate kinase domain. 相似文献
138.
Antigen-induced production of migration inhibitory factor (MIF) by sensitized lymphocytes requires macrophages to effectively stimulate lymphocytes with soluble antigen in vitro. The present study showed that macrophage-depleted lymphocytes of sensitized guinea pigs could be activated with antigens when the culture supernatant of peritoneal adherent cells pulse-stimulated with a macromolecular fraction of bacterial lipopolysaccharide (LPS) was added to the lymphocyte culture. The apparent macrophage-replacing activity was found in the fraction which emerged slightly ahead of serum albumin upon gel filtration of the culture supernatant, and the activity was shown to be destroyed by heating at 65 °C for 30 min or by trypsin digestion. These results appeared to show that the activity was due to a protein component, most probably released from macrophages. Two-step culture experiments revealed that the soluble factor should be present in the early stage of the culture to activate the macrophage-depleted immune lymphocytes with antigen, as well as in the later stage when the presence of antigen in the medium is no longer required. Furthermore, the factor was shown to act in the activation of a T-cell-enriched fraction of immune lymphocytes. The factor appeared to be playing some essential role in making an antigenic stimulus effective for the activation of immune lymphocytes. 相似文献
139.
Stem cell function during plant vascular development 总被引:1,自引:0,他引:1
A. Elo J. Immanen K. Nieminen Y. Helariutta 《Seminars in cell & developmental biology》2009,20(9):1097-1106
While many regulatory mechanisms controlling the development and function of root and shoot apical meristems have been revealed, our knowledge of similar processes in lateral meristems, including the vascular cambium, is still limited. Our understanding of even the anatomy and development of lateral meristems (procambium or vascular cambium) is still relatively incomplete, let alone their genetic regulation. Research into this particular tissue type has been mostly hindered by a lack of suitable molecular markers, as well as the fact that thus far very few mutants affecting plant secondary development have been described. The development of suitable molecular markers is a high priority in order to help define the anatomy, especially the location and identity of cambial stem cells and the developmental phases and molecular regulatory mechanisms of the cambial zone. To date, most of the advances have been obtained by studying the role of the major plant hormones in vascular development. Thus far auxin, cytokinin, gibberellin and ethylene have been implicated in regulating the maintenance and activity of cambial stem cells; the most logical question in research would be how these hormones interact during the various phases of cambial development. 相似文献
140.
The inhibition of the cytoplasmic 5'-nucleotidase (EC 3.1.3.5) by its product, inosine, was studied with a partially purified preparation of the enzyme from rat liver. Inhibition of Pi production was found to be due to exchange of the inosine moiety between inosine and IMP. Exchange was not catalysed by reversal of the hydrolytic reaction, suggesting, instead, the mediation of an enzyme-phosphate intermediate. Two models for the catalytic mechanism are proposed and rate equations for the dependence of Pi production on inosine concentration are derived. The experimentally determined dependence was consistent with a mechanism in which hydrolysis of the enzyme-phosphate intermediate occurred only when it was unoccupied by inosine. This conclusion suggests that inosine analogues that cannot participate in exchange should inhibit the enzyme. Such inhibitors might be useful in defining the enzyme's physiological role or as pharmacological agents to decrease breakdown of purine nucleotides. The possibility that nucleoside exchange provides an alternative route for the phosphorylation of mutagenic or cytotoxic nucleoside analogues should also be considered. 相似文献