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111.
Ong SY Pratap CB Wan X Hou S Abdul Rahman AY Saito JA Nath G Alam M 《Journal of bacteriology》2012,194(8):2115-2116
We report here the complete genome sequence of Salmonella enterica subsp. enterica serovar Typhi P-stx-12, a clinical isolate obtained from a typhoid carrier in India. 相似文献
112.
A new gene, designated as BnPrx (GenBank Accession No. DQ078754), was isolated from oilseed rape (Brassica napus) by SMART Rapid Amplification of cDNA Ends (RACE). The full-length cDNA is 1307 bp long and contains a 1062 bp open reading frame (ORF), which encodes a 354 amino acid peroxidase precursor, with a 31 aa N-terminal signal peptide and a 15 aa C-terminal propeptide. The putative protein has a molecular weight of 38.86 kDa and a calculated pI of 5.85. BnPrx shares high identity with HRPC (89%). BnPrx possesses all active residues and two Ca2+ sites present in Horseradish peroxidase isoenzymes C (HRPC) as well as six N-glycosylation sites. The predicted 3-D structure of BnPrx is very similar to that of HRPC. Assisted by genomic walking technology, the genomic DNA of BnPrx was also cloned, consisting of 3 introns and 4 exons. Thirty-two TATA boxes, 18 CAAT boxes and many cis-elements, such as WUN, MeJR, were found in its promoter region. Southern blot analysis indicated that BnPrx belonged to a small gene family. Northern blot analysis revealed that BnPrx was constitutively expressed in all tested tissues, including roots, stems and leaves, with the high expression in leaves and stems. The expression of BnPrx could be induced by methyl jasmonate (MeJA), salicylic acid (SA), cold and H2O2. The cloning and characterizing of BnPrx might not only help us understand the physiological function and molecular evolution of the large peroxidase gene family more comprehensively, but also provide an alternative way of seeking a more effective and economical substitute for HRPC. 相似文献
113.
Beth A. Polidoro Kent E. Carpenter Lorna Collins Norman C. Duke Aaron M. Ellison Joanna C. Ellison Elizabeth J. Farnsworth Edwino S. Fernando Kandasamy Kathiresan Nico E. Koedam Suzanne R. Livingstone Toyohiko Miyagi Gregg E. Moore Vien Ngoc Nam Jin Eong Ong Jurgenne H. Primavera Severino G. Salmo III Jonnell C. Sanciangco Sukristijono Sukardjo Yamin Wang Jean Wan Hong Yong 《PloS one》2010,5(4)
Mangrove species are uniquely adapted to tropical and subtropical coasts, and although relatively low in number of species, mangrove forests provide at least US $1.6 billion each year in ecosystem services and support coastal livelihoods worldwide. Globally, mangrove areas are declining rapidly as they are cleared for coastal development and aquaculture and logged for timber and fuel production. Little is known about the effects of mangrove area loss on individual mangrove species and local or regional populations. To address this gap, species-specific information on global distribution, population status, life history traits, and major threats were compiled for each of the 70 known species of mangroves. Each species'' probability of extinction was assessed under the Categories and Criteria of the IUCN Red List of Threatened Species. Eleven of the 70 mangrove species (16%) are at elevated threat of extinction. Particular areas of geographical concern include the Atlantic and Pacific coasts of Central America, where as many as 40% of mangroves species present are threatened with extinction. Across the globe, mangrove species found primarily in the high intertidal and upstream estuarine zones, which often have specific freshwater requirements and patchy distributions, are the most threatened because they are often the first cleared for development of aquaculture and agriculture. The loss of mangrove species will have devastating economic and environmental consequences for coastal communities, especially in those areas with low mangrove diversity and high mangrove area or species loss. Several species at high risk of extinction may disappear well before the next decade if existing protective measures are not enforced. 相似文献
114.
Zhihua Liao Yifu Gong Guoyin Kai Kaijing Zuo Min Chen Qiumin Tan Yamin Wei Liang Guo Feng Tan Xiaofen Sun Kexuan Tang 《Molecular Biology》2005,39(1):11-17
Geranylgeranyl diphosphate synthase (GGPPS) [EC 2.5.1.29] catalyzes the biosynthesis of geranylgeranyl diphosphate (GGPP), which is a key precursor for diterpenes and, in particular, Taxol, one of the most potent antitumor drugs. In order to investigate the role of GGPP synthase in Taxol biosynthesis, we cloned, characterized, and functionally expressed the GGPPS gene from Taxus media. Using the genome walking strategy, a 3743-bp genomic sequence of T. media was isolated which contained a 1182-bp open reading frame (ORF) encoding a 393-amino acid polypeptide that showed a close similarity to other plant GGPPSs. Subsequently, the full-length cDNA of the GGPPS gene of T. media (designated TmGGPPS) was amplified by RACE. Bioinformatic analysis showed that TmGGPPS was an intron-free gene, and its deduced polypeptide contained all five conserved domains and functional aspartate-rich motifs of the prenyltransferases. By constructing the phylogenetic tree of plant GGPPSs, it was found that plant-derived GGPPSs could be divided into two classes, those of angiosperms and gymnosperms, which might have evolved in parallel from the same ancestor. To our knowledge, this was the first report that the geranylgeranyl diphosphate synthase genes were free of introns and evolved in parallel in both angiosperms and gymnosperms. The coding sequence of TmGGPPS was expressed through functional complementation in a yeast mutant lacking GGPPS activity (SFNY368), and the transgenic yeast was shown to have this activity. This was also the first time SFNY368 was used to identify the function of plant-derived GGPPSs. Furthermore, investigation of the effect of methyl jasmonate (MeJA) on the expression of TmGGPPS showed that MeJA-treated T. media cultured cells had much higher expression of TmGGPPS than untreated cells.From Molekulyarnaya Biologiya, Vol. 39, No. 1, 2005, pp. 14–20.Original English Text Copyright © 2005 by Zhihua Liao, Yifu Gong, Guoyin Kai, Kaijing Zuo, Min Chen, Qiumin Tan, Yamin Wei, Liang Guo, Feng Tan, Xiaofen Sun, Kexuan Tang.This article was submitted by the authors in English. 相似文献
115.
据调查统计,甘肃小陇山有毒被子植物共107种,其有毒化学成分主要为非蛋白质氨基酸、肽类、生物碱、酚类衍生物、萜类、甙类和无机及有机物等.对有毒植物的民间用毒、解毒方法进行了调查. 相似文献
116.
Seng HL Ong HK Rahman RN Yamin BM Tiekink ER Tan KW Maah MJ Caracelli I Ng CH 《Journal of inorganic biochemistry》2008,102(11):1997-2011
The binding selectivity of the M(phen)(edda) (M = Cu, Co, Ni, Zn; phen = 1,10-phenanthroline, edda = ethylenediaminediacetic acid) complexes towards ds(CG)6, ds(AT)6 and ds(CGCGAATTCGCG) B-form oligonucleotide duplexes were studied by CD spectroscopy and molecular modeling. The binding mode is intercalation and there is selectivity towards AT-sequence and stacking preference for A/A parallel or diagonal adjacent base steps in their intercalation. The nucleolytic properties of these complexes were investigated and the factors affecting the extent of cleavage were determined to be: concentration of complex, the nature of metal(II) ion, type of buffer, pH of buffer, incubation time, incubation temperature, and the presence of hydrogen peroxide or ascorbic acid as exogenous reagents. The fluorescence property of these complexes and its origin were also investigated. The crystal structure of the Zn(phen)(edda) complex is reported in which the zinc atom displays a distorted trans-N4O2 octahedral geometry; the crystal packing features double layers of complex molecules held together by extensive hydrogen bonding that inter-digitate with adjacent double layers via π…π interactions between 1,10-phenanthroline residues. The structure is compared with that of the recently described copper(II) analogue and, with the latter, included in molecular modeling. 相似文献
117.
Both enantiomers of 3-hydroxyalkanoates and -alkanones were prepared by the diastereocontrolled addition of enolates to ketones containing (R)-6-methyl-1,3-oxathiane moiety as a chiral auxiliary; a formation of enolate from samarium(II) iodide and alpha-bromoamide is also discussed. 相似文献
118.
Chediack JG Caviedes-Vidal E Fasulo V Yamin LJ Karasov WH 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2003,173(3):187-197
We tested predictions that: (1) absorption of water-soluble probes decreases with increasing molecular size, consistent with movement through effective pores in epithelia, and (2) absorption of probes is enhanced when measured in the presence of luminal nutrients, as predicted for paracellular solvent drag. Probes (L-arabinose, L-rhamnose, perseitol, lactulose; MW 150.1-342.3 Da) were gavaged in nonanesthetized House sparrows ( Passer domesticus), or injected into the pectoralis, and serially measured in plasma. Bioavailability was calculated as F=AUC by gavage/AUC by injection, where AUC is the area under the curve of plasma probe concentration vs. time. Consistent with predictions, F declined with probe size by 75% from the smallest to the largest probe, and absorption of probes increased by 40% in the presence of luminal glucose or food compared to a mannitol control. Absorption of water-soluble probes by sparrows is much higher than in humans, which is much higher than in rats. These differences seem mainly attributable to differences in paracellular solvent flux and less to differences in effective paracellular pore size. 相似文献
119.
120.
Gunn D Akuche C Baryza J Blue ML Brennan C Campbell AM Choi S Cook J Conrad P Dixon B Dumas J Ehrlich P Gane T Joe T Johnson J Jordan J Kramss R Liu P Levy J Lowe D McAlexander I Natero R Redman AM Scott W Seng T Sibley R Wang M Wang Y Wood J Zhang Z 《Bioorganic & medicinal chemistry letters》2005,15(12):3053-3057
4,5-Disubstituted cis-pyrrolidinones were investigated as inhibitors of type II 17beta-hydroxysteroid dehydrogenase (17beta-HSD). Early structure-activity relationship patterns for this class of compounds are discussed. 相似文献