iscr regulates rnase ls activity by repressing rnla transcription.the escherichia coli endoribonuclease ls was originally identified as a potential antagonist of bacteriophage t4. when the t4 dmd gene is defective, rnase ls cleaves t4 mrnas and antagonizes t4 reproduction. this rnase also plays an important role in rna metabolisms in e. coli. rnla is an essential gene for rnase ls activity, but the transcriptional regulation of this gene remains to be elucidated. an fe-s cluster protein, iscr, acts as a transcription factor and controls the expression of genes ...201020421606
combination of dna ligase reaction and gold nanoparticle-quenched fluorescent oligonucleotides: a simple and efficient approach for fluorescent assaying of single-nucleotide polymorphisms.a new fluorescent sensing approach for detection of single-nucleotide polymorphisms (snps) is proposed based on the ligase reaction and gold nanoparticle (aunps)-quenched fluorescent oligonucleotides. the design exploits the strong fluorescence quenching of aunps for organic dyes and the difference in noncovalent interactions of the nanoparticles with single-stranded dna (ssdna) and double-stranded dna (dsdna), where ssdna can be adsorbed onto the surface of aunps while dsdna cannot be. in the a ...201020726510
a mutation within the β subunit of escherichia coli rna polymerase impairs transcription from bacteriophage t4 middle promoters.during infection of escherichia coli, bacteriophage t4 usurps the host transcriptional machinery, redirecting it to the expression of early, middle, and late phage genes. middle genes, whose expression begins about 1 min postinfection, are transcribed both from the extension of early rna into middle genes and by the activation of t4 middle promoters. middle-promoter activation requires the t4 transcriptional activator mota and coactivator asia, which are known to interact with σ(70), the specifi ...201020729353
swnt-mwnt hybrid filter attains high viral removal and bacterial inactivation.we describe the concept and demonstrate the efficacy of a novel swnt-mwnt hybrid filter for the removal and inactivation of microbial pathogens from water. the filter is composed of a thin swnt layer (0.05 mg cm(-2)) on top of a thicker mwnt layer (0.27 mg cm(-2)) supported by a microporous support membrane. the swnt-mwnt filter exhibits high log removal of several model viruses (ms2, prd1, and t4 bacteriophages) by depth filtration, which predominantly takes place in the thicker and more unifor ...201021090770
efficacy of a broad host range lytic bacteriophage against e. coli adhered to urothelium.persistent urinary tract infections (uti) are often caused by e. coli adhered to urothelium. this type of cells is generally recognized as very tolerant to antibiotics which renders difficult the treatment of chronic uti. this study investigates the use of lytic bacteriophages as alternative antimicrobial agents, particularly the interaction of phages with e. coli adhered to urothelium and specifically determines their efficiency against this type of cells. the bacterial adhesion to urothelium w ...201021140149
trimerization of murine tnf ligand family member light increases the cytotoxic activity against the fm3a mammary carcinoma cell line.light is a member of the tumor necrosis factor ligand superfamily, which plays important roles in inflammatory and immune responses. light forms a membrane-anchored homotrimeric complex on the cell surface and is often processed as a soluble protein. recombinant soluble human light produced by mammalian cells or escherichia coli is functional at nanomolar concentrations. however, there is little information about the biological activity of mouse light (mlight) because of the difficulty in produc ...201121400099
liposomes containing glucosyl ceramide specifically bind t4 bacteriophage: a self-assembling nanocarrier formulation.a unique formulation is described comprising liposomes containing glucosyl ceramide (glucer) in the lipid bilayer to which bacteriophage t4 was attached. binding of the phage t4 did not occur to glycolipids, such as galactosyl ceramide, containing an aldose in which the c-2 or c-4 conformations were not identical to glucose. these results strongly support previous proposals that glucose is a major receptor moiety for t4 binding to escherichia coli. by using the binding of t4 to liposomal glucer, ...201121401373
microbial removal from the separated liquid fraction of anaerobically digested pig manure in meso-scale integrated constructed wetlands.the aim was to investigate microbial removal from the liquid fraction of anaerobically digested pig manure in meso-scale integrated constructed wetlands (icw's) over a 13 month period. four treatments were investigated: t1 (standard), t2 (effluent recycling), t3 (high nutrient loading), and t4 (high flow rate). mean counts of yeasts and moulds and spore-forming bacteria were higher in t3 and t4 than in t1 and t2 (p<0.05). flow through the cells reduced mean counts of coliform, yeasts and moulds ...201121852121
Determinants of the cytotoxicity of PrrC anticodon nuclease and its amelioration by tRNA repair.Breakage of tRNA(Lys(UUU)) by the Escherichia coli anticodon nuclease PrrC (EcoPrrC) underlies a host antiviral response to phage T4 infection that is ultimately thwarted by a virus-encoded RNA repair system. PrrC homologs are prevalent in other bacteria, but their activities and substrates are not defined. We find that induced expression of EcoPrrC is toxic in Saccharomyces cerevisiae and E. coli, whereas the Neisseria meningitidis PrrC (NmePrrC) is not. PrrCs consist of an N-terminal NTPase mo ...201222101242
Diffusion of bacteriophages through artificial biofilm models.The simple two-chamber diffusion method was improved to study the diffusion properties of bacteriophage (phage) T4 through a model biofilm agarose gel membrane (AGM) embedded with dead host Escherichia coli K12 cells. The apparent diffusion coefficient (D(app) ) of phage T4 was calculated to be 2.4 × 10(-12) m(2) /s in 0.5% AGM, which was lower than the coefficient of 4.2 × 10(-12) m(2) /s in 0.5% AGM without host cells. The phage adsorption process by dead host cells slowed the apparent phage ...201122058083
Displaying items 601 - 610 of 610