Mitomycin C induces both MC-mono-dG and cross-linked dG-adducts in vivo. Interstrand (ICL) dG-MC-dG-DNA adducts can prevent strand separation. In Escherichia coli cells, UvrABC repairs ICL lesions that cause DNA bending. The mechanisms consequences of NER dG-MC-dG do not induce bending remain unclear. Using fragments containing a or an adduct, we found (i) incises only at the adducts; (ii) makes three types incisions on adduct: type 1, single 5′ incision 1 3′ other; 2, dual 3, strands; (iii)...

// Mao-Wen Weng 1, * , Hyun-Wook Lee Bongkun Choi Hsiang-Tsui Wang Yu Hu 1 Manju Mehta Dhimant Desai 2 Shantu Amin Yi Zheng Moon-Shong Tang Departments of Environmental Medicine, Pathology and New York University School Tuxedo, NY 10987, USA Department Pharmacology, Penn State College Hershey, PA 17033, These authors have contributed equally to this work Correspondence to: Tang, email: moon-shong.tang@nyumc.org Keywords: aflatoxin B1, hepatocellular carcinoma, p53 codon 249 mutations,...

Mycotoxins are likely to be converted into masked forms when subjected plant metabolism or food processing. These of mycotoxins together with their prototypes may cause mixture toxicity effects, causing adverse effects on animal welfare and productivity. The structure elucidation is the most challenging task in mycotoxin research due limitations traditional analysis methods. To assist rapid identification mycotoxins, we developed a data-driven online prediction tool, MycotoxinDB, based...

Ochratoxin A (OTA) is a mycotoxin that can contaminate wide range of crops such as grains and grapes. In this study, novel fungal mutant strain (FS-UV-21) with high OTA degradation rate (74.5%) was obtained from Aspergillus niger irradiated ultraviolet light (15 W for 20 min). The effect pH, temperature, inoculation concentration on the by FS-UV-21 investigated, results revealed detoxification optimal (89.4%) at pH 8 temperature 30 °C. Ultra-performance liquid chromatography-tandem mass...

Zearalenone (ZEN) and its derivatives pose a serious threat to global food quality animal health. The use of enzymes degrade mycotoxins has become popular method counter this threat. In study, Aspergillus niger ZEN-S-FS10 extracellular enzyme solution with ZEN-degrading effect was separated purified prepare the biological enzyme, FSZ, that can ZEN. degradation rate FSZ ZEN 75−80% (pH = 7.0, 28 °C). function in temperature range 28−38 °C pH 2.0−7.0 also (α-ZAL, β-ZOL, ZAN). According kinetics...

Traditional methods used to detect fungi or mycotoxins are time-consuming and prevent real-time monitoring. In this study, solid-phase microextraction combined with full two-dimensional gas chromatography time-of-flight mass spectrometry was utilized volatile organic compounds (VOCs) produced by during grain infestation predictive F. graminearum PH-1 in wheat. The results show that the VOCs emitted can distinguish strains at different growth stages. matrices (potato dextrose agar medium...

We have established that UvrABC nuclease is equally efficient in cutting mitomycin C (MC)−DNA monoadducts formed at different sequences and the degree of represents extent drug−DNA bonding. Using this method we determined effect C5 cytosine methylation on DNA monoalkylation by MC related analogues N-methyl-7-methoxyaziridinomitosene (MS-NMA) 10-decarbamoylmitomycin (DC-MC). found CpG sites greatly enhances MS-NMA adduct formation those while reducing non-CpG sequences. In contrast, although...

Both prokaryotic and eukaryotic cells have the capacity to repair DNA damage preferentially in transcribed strand of actively expressed genes. However, we found that several types damage, including cyclobutane pyrimidine dimers (CPDs) are repaired with equal efficiency both nontranscribed strands adenine phosphoribosyltransferase (APRT) gene Chinese hamster ovary cells. We further that, two mutant cell lines which entireAPRT promoter region has been deleted, CPDs still efficiently...

Using phosphocellulose followed by single-stranded DNA-cellulose chromatography for purification of UvrC proteins from overproducing cells, we found that elutes at two peaks: 0.4 m KCl (UvrCI) and 0.6 (UvrCII). Both forms have a major peptide band (>95%) the same molecular weight identical N-terminal amino acid sequences, which are consistent with initiation codon being unusual GTG site. active in incising UV-irradiated, supercoiled phiX-174 replicative form I DNA presence UvrA UvrB...

We have found that 7,12-dimethylbenz[a]anthracene-syn-diol epoxide (syn-DMBADE)-modified DNA fragments are sensitive to UvrABC incision. The incisions occur mainly seven bases 5' and four 3' of a syn-DMBADE-modified adenine or guanine residue. kinetics incision at different sequences in fragment the same, extent is proportional syn-DMBADE concentration. On basis these results, we concluded on syn-DMBADE−DNA adducts independent sequence quantitative. Using method, analyzed binding spectrum...

Mycotoxins can accumulate in various feeds and thus may get duck meat, which have severe food safety public health implications. This study examined mycotoxins veterinary medications meat marketed eight marketplaces around China. For the determination of mycotoxins, including aflatoxin B1 (AFB1), B2 (AFB2), M1 (AFM1), T-2 toxin, zearalenone (ZEN), ochratoxin A (OTA), a liquid-chromatography tandem mass spectrometry (LC-MS/MS) method was validated. Overall, 13 out 48 samples (27%) presented...

UV irradiation induces the dimerization of synthetic single-stranded, 80-mer oligonucleotides with self-complementary, alternating purine-pyrimidine sequences, and terminal 5'- 3'-thymines; this process can be reversed by photoreactivation. The UV-induced 160-mers are sensitive to digestion restriction enzyme SnaBI, but monomers insensitive digestion, indicating that stabilizes formation double-stranded DNA. These results suggest these oligonucleotide substrates a novel cyclobutane thymine...

Abstract Mitomycin C (MC) forms at least nine different covalent DNA adducts including an N2-2’-deoxyguanosine monoadduct (MC-mono-dG) and inter- intrastrand bis-adducts with 2’-deoxyguanosine (dG) in vivo. Inter-strand cross-linked (ICL) dG-MC-dG-DNA can prevent strand separation, therefore, the MC antitumor activity is most likely derived from formation of ICL-MC adducts. In Escherichia coli cells, UvrABC, nucleotide excision repair (NER) enzyme complex ICL psoralen lesions that cause...