Human cells contain a protein that binds to UV-irradiated DNA with high affinity. This protein, the damaged DNA-binding (DDB), is absent from some xeroderma pigmentosum complementation group E cell strains; therefore, it has been suggested may be damage recognition subunit of human excision nuclease complex. However, identity UV photoproduct bound by DDB and role this in nucleotide repair have controversial. In study, we used several synthetic substrates, each which contains one major...

Pyrimidine (6-4) pyrimidone photoproduct is the second most abundant UV in DNA. Recently, it was reported that Drosophila melanogaster cell-free extracts restored biological activity of photo-product-containing DNA a light-dependent reaction (Todo, T., Takemori, H., Ryo, Ihara, M., Matsunaga, Nikaido, O., Sato, K., and Nomura, T. (1993) Nature 361, 372-374) concomitant with loss antigenic sites photoproduct-caused alkali-labile sites. In present study we show but not its Dewar isomer...

Abstract Deoxyoligonucleotide 49-mers containing a central cis-syn, trans-syn-I, (6-4), or Dewar photoproduct of TpT were constructed for use in repair and replication studies by ligation shorter photoproduct-containing oligonucleotides. A (6-4) product-containing 6-mer was prepared 3.4% yield 254 nm irradiation d(AATTAA) converted nearly quantitative to the isomer with Pyrex- Mylar-filtered medium-pressure mercury arc light. d(CGAATTAAGC) site-specific cis-syn trans-syn-I dimer via...

Abstract Aim More than 90 marine fish species in the Mediterranean have been determined to be alien of Red Sea origin date and therefore it is important prioritize research into cataloguing their distribution impacts. The aims this study were establish a barcode library for fishes probable initiate analyses invasion dynamics. Location Sea. Methods Specimens exotic collected directly from off coast Lebanon or obtained markets Lebanon. Samples first identified morphologically later barcoded...

In this communication we report the construction of a printed circuit board which mounts directly to vacuum chamber mass spectrometer and produces RF waveforms needed by many nonmass-selective devices such as ion guides funnels. Our device is designed replace standard KF40 flange, can maintain pressures less than 10–6 Torr, contains circuitry open-source Wisconsin Oscillator power supply generate 1–4 MHz up 200 Vp-p. iteration Oscillator, also introduce variable resistor control output...

The cis,syn and (6-4) products of dipyrimidine sites are the major mutagenic lethal UV photoproducts in DNA. To investigate their relative susceptibilities to repair other factors such as sequence context lesions complementary strand that might influence efficiencies, we constructed 49-mer duplexes containing site-specific thymidylyl(3',5')thymidine at central locations. Using these substrates, measured binding Escherichia coli DNA photolyase dimers four contexts two close proximity on...

We have discovered a new DNA endonuclease in the fission yeast Schizosaccharomyces pombe which recognizes cyclobutane pyrimidine dimers and (6–4) pyrimidine-pyrimidone photoproducts. S.pombe (SPDE) catalyzes single ATPindependent incision immediately 5′ to UV photoproduct generates termini containing 3′ hydroxyl phosphoryl groups. Based on these properties, we propose that SPDE may function repair capacity, representing initial recognition/ cleavage step of excision pathway.

Abstract Dust rains may be particularly effective at delivering microorganisms, yet their biodiversities have been seldom examined. During 2011 and 2012 in Beirut, Lebanon, 16 of 21 collected rainfalls appeared dusty. Trajectory modelling air mass origins was consistent with North African sources least one Southwest Asian source. As much as ~4 g particulate matter, ~20 μg DNA 50 million colony forming units were found deposited per square meter during each lasting less than day. Sequencing...

The mutation spectra of cis-syn, trans-syn-I, (6−4), and Dewar pyrimidone photoproducts the TT site AATTAA TATTAT in (−) strand a heteroduplex M13 vector were obtained an excision photoreversal repair deficient Escherichia coli host under SOS conditions. Oligonucleotides containing site-specific annealed to complementary uracil-containing (+) that contained one or more unique pairs nucleotide mismatches used prime synthesis with DNA polymerase dNTPs. Following synthesis, reaction mixtures...

The 24-hour urine protein/creatinine (U[P/C]) ratio was examined in 19 healthy dogs and 38 with protein-losing nephropathies. A positive correlation existed between the U(P/C) protein output per kilogram of body weight. 18 less than 0.2; one dog had a 0.38. median glomerulonephritis (n = 26) amyloidosis 6) 5.73 22.50, respectively. chronic interstitial nephritis 2.89. In presence hypoalbuminemia (albumin or equal to 1.5 g/dl), U/(P/C) greater 1 indicated nephrotic syndrome. Severe...

The role of photoproduct structure, 3′ → 5′ exonuclease activity, and processivity on polynucleotide synthesis past photoproducts thymidylyl-(3′ 5′)-thymidine was investigated. Both Moloney murine leukemia virus reverse transcriptase exonuclease-deficient (exo−) Vent polymerase were blocked by all photoproducts, whereas Taq could slowly bypass the cis-syn dimer. T7 RNA able to in order cis-syn> Dewar > (6-4) trans-syn-II. Klenow fragment not any but an exo−mutant dimer a greater extent than...

Among the genes of Rhizobium meliloti SU47 that affect nitrogen-fixing symbiosis with alfalfa are nod genes, in which mutations block nodule induction, and exo allow formation but rhizobial exopolysaccharide production as well invasion nitrogen fixation. To investigate whether an exo+ bacterium can "help" (that is, reverse symbiotic defect of) mutant trans, we have coinoculated pairs rhizobia different genotypes. Coinoculant genotypes were chosen so helper strain was nif while "indicator"...

Abstract Two murine mAb have been generated with a reactivity toward 30,000 m.w. DNA binding protein found on the cell surface of human leukocytes; 12A has an IgG1/k isotype, and 24T IgG2b/k isotype. Both react domain or adjacent region putative receptor inhibit [3H]DNA to PBMC at concentrations as low 100 ng/ml. Stoichiometric studies indicate that both monocytes T cells kDa 10(-7) M; about 0.5 x 10(6) molecules bind per saturation. Flow cytometry indicated 67% lymphocytes 98% bore...

Microbial transformation of steroids has been extensively used for the synthesis steroidal drugs, that often yield novel analogues, not easy to obtain by chemical synthesis. We report here fungal a synthetic drug, exemestane, treatment breast cancer and function through inhibition aromatase enzyme. anti-cancer steroid, exemestane (1), was investigated using two filamentous fungi. Incubation 1 with fungi Macrophomina phaseolina, Fusarium lini afforded three new,...