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931.
Mallette FA Mattiroli F Cui G Young LC Hendzel MJ Mer G Sixma TK Richard S 《The EMBO journal》2012,31(8):1865-1878
In response to DNA damage, cells initiate complex signalling cascades leading to growth arrest and DNA repair. The recruitment of 53BP1 to damaged sites requires the activation of the ubiquitination cascade controlled by the E3 ubiquitin ligases RNF8 and RNF168, and methylation of histone H4 on lysine 20. However, molecular events that regulate the accessibility of methylated histones, to allow the recruitment of 53BP1 to DNA breaks, are unclear. Here, we show that like 53BP1, the JMJD2A (also known as KDM4A) tandem tudor domain binds dimethylated histone H4K20; however, JMJD2A is degraded by the proteasome following the DNA damage in an RNF8-dependent manner. We demonstrate that JMJD2A is ubiquitinated by RNF8 and RNF168. Moreover, ectopic expression of JMJD2A abrogates 53BP1 recruitment to DNA damage sites, indicating a role in antagonizing 53BP1 for methylated histone marks. The combined knockdown of JMJD2A and JMJD2B significantly rescued the ability of RNF8- and RNF168-deficient cells to form 53BP1 foci. We propose that the RNF8-dependent degradation of JMJD2A regulates DNA repair by controlling the recruitment of 53BP1 at DNA damage sites. 相似文献
932.
933.
Characterization of Staphylococcus aureus Strains Associated with Food Poisoning in Shenzhen, China 总被引:1,自引:0,他引:1
X Yan B Wang X Tao Q Hu Z Cui J Zhang Y Lin Y You X Shi H Grundmann 《Applied and environmental microbiology》2012,78(18):6637-6642
To characterize isolates of Staphylococcus aureus that were associated with staphylococcal food poisoning between 2006 and 2009 in Shenzhen, Southern China, a total of 52 Staphylococcus aureus isolates from 11 outbreaks were analyzed by using multilocus sequence typing (MLST), spa typing, and pulsed-field gel electrophoresis (PFGE). PCR analysis was used to analyze the staphylococcal enterotoxin (SE) genes sea to sei, and antimicrobial susceptibility testing was also performed. ST6 was the most dominant sequence type (ST), constituting 63.5% (34/52) of all of the isolates in 7 outbreaks. The next most common ST was ST943, which constituted 23.1% (12/52) of the isolates that were collected from 3 outbreaks. t701, t091, and t2360 were the most predominant spa types, constituting 67.3% (35/52) of the isolates that were collected from 11 outbreaks. Three PFGE types, (types A, B, and C) were the most frequently observed types, constituting 84.6% (44/52) of all of the isolates. The enterotoxin gene that we detected most frequently was sea (45/52; 86.5%). Four SE gene profiles were observed, including sea (n = 45), sec-seh (n = 3), seb (n = 2), and seg-sei (n = 2). With respect to antibiotic resistance, penicillin resistance was the most common (96.2%; 50/52), followed by resistance to tetracycline (28.8%; 15/52). Approximately 30.8% (16/52) of the isolates were resistant to at least two antibiotics, and 7.7% (4/52) of the isolates were resistant to three or more drugs. The two predominant S. aureus lineages, (i) PFGE types A and B with ST6 and (ii) PFGE type C with ST943, were identified in the outbreaks. 相似文献
934.
Lagerstroemia menglaensis C. H. Gu, M. C. Ji & D. D. Ma, a new species of Lythraceae from Xishuangbanna, Yunnan, China is described and illustrated. The morphological characteristics of the new species and two morphologically similar species (L. guilinensis and L. venusta) are compared, and a key to distinguish between them is provided. 相似文献
935.
Different nutrients were added into the solid fermentation of woody biomass, Populus tomentosa, to improve pretreatment by a white rot fungus, Trametes velutina. Fungal pretreatment supplemented with trace elements resulted in large amount of lignin loss but low degradation of carbohydrate. Only 12.6?% of Klason lignin was left in the residues pretreated by T. velutina for 8?weeks supplemented with 1?% trace elements (TE group). When fungal-pretreated residues were subjected to enzymatic hydrolysis for 96?h, a maximum reducing sugar yield of 44?% was obtained from the TE group at the 8th week, 2.3 times higher than that of untreated samples. In addition, the highest ethanol yield of 22?% was observed by the fermentation of 8-week pretreated residues from the basic medium plus trace element group, which was five times more than that of untreated samples. 相似文献
936.
Zhang B Ni B Lü S Cui D Liu M Gong H Han F 《International journal of biological macromolecules》2012,50(3):701-706
A novel substance, cationic acetylcholine potato starch (CAPS), was developed for the first time. The synthesis process had three steps: first, carboxymethyl potato starch (CMPS) was synthesized under sodium hydroxide alkaline condition and in isopropyl alcohol organic media; second, bromocholine chloride (BCC) was synthesized with sulphuric acid as a catalytic agent; finally, CAPS was synthesized by the reaction of CMPS with BCC in N,N'-dimethylformamide (DMF). The degree of substitution (DS) of CAPS was determined by ammonia gas-sensing electrode and elemental analysis. CAPS was characterized by Fourier transformed infrared (FTIR) and near infrared (FTNIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). 相似文献
937.
S Sun X Yang Y Yuan X Dai Y Yan H Cao T Luo R Guo X Wang Y Song R Yang Y Zhang Y Cui 《Journal of bacteriology》2012,194(19):5447-5448
We deciphered the genome of Yersinia pestis strain 2501, isolated from the Junggar Basin, a newly discovered great gerbil plague focus in Xinjiang, China. The total length of assembly was 4,597,322 bp, and 4,265 coding sequences were predicted within the genome. It is the first Y. pestis genome from this plague focus. 相似文献
938.
Qin T Cui Y Cen Z Liang T Ren H Yang X Zhao X Liu Z Xu L Li D Song Y Yang R Shao Z Song Y 《Journal of bacteriology》2012,194(5):1251-1252
Legionella (Fluoribacter) dumoffii is one of the agents causing Legionnaires' disease. Here, we used Illumina second-generation sequencing technology to decipher for the first time the whole-genome sequences of two strains of this species, TEX-KL and NY-23. The assembly results for both strains consist of one chromosome and two plasmids. 相似文献
939.
Wenxiao Liu Zhigang Jing Qixing Ou Buyun Cui Yongqun He Qingmin Wu 《Journal of bacteriology》2012,194(22):6321
From an aborted bovine fetus in China, a bacterial strain named NI was isolated and identified as Brucella melitensis by a PCR assay. Strain NI was further characterized as B. melitensis biovar 3 using biochemical assays. Here we report the complete genome sequence of strain NI. 相似文献