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111.
Genomic sequence of the pathogenic and allergenic filamentous fungus Aspergillus fumigatus 总被引:1,自引:0,他引:1
Nierman WC Pain A Anderson MJ Wortman JR Kim HS Arroyo J Berriman M Abe K Archer DB Bermejo C Bennett J Bowyer P Chen D Collins M Coulsen R Davies R Dyer PS Farman M Fedorova N Fedorova N Feldblyum TV Fischer R Fosker N Fraser A García JL García MJ Goble A Goldman GH Gomi K Griffith-Jones S Gwilliam R Haas B Haas H Harris D Horiuchi H Huang J Humphray S Jiménez J Keller N Khouri H Kitamoto K Kobayashi T Konzack S Kulkarni R Kumagai T Lafon A Lafton A Latgé JP Li W Lord A Lu C Majoros WH May GS 《Nature》2005,438(7071):1151-1156
Aspergillus fumigatus is exceptional among microorganisms in being both a primary and opportunistic pathogen as well as a major allergen. Its conidia production is prolific, and so human respiratory tract exposure is almost constant. A. fumigatus is isolated from human habitats and vegetable compost heaps. In immunocompromised individuals, the incidence of invasive infection can be as high as 50% and the mortality rate is often about 50% (ref. 2). The interaction of A. fumigatus and other airborne fungi with the immune system is increasingly linked to severe asthma and sinusitis. Although the burden of invasive disease caused by A. fumigatus is substantial, the basic biology of the organism is mostly obscure. Here we show the complete 29.4-megabase genome sequence of the clinical isolate Af293, which consists of eight chromosomes containing 9,926 predicted genes. Microarray analysis revealed temperature-dependent expression of distinct sets of genes, as well as 700 A. fumigatus genes not present or significantly diverged in the closely related sexual species Neosartorya fischeri, many of which may have roles in the pathogenicity phenotype. The Af293 genome sequence provides an unparalleled resource for the future understanding of this remarkable fungus. 相似文献
112.
The perception of surface albedo (lightness) is one of the most basic aspects of visual awareness. It is well known that the apparent lightness of a target depends on the context in which it is embedded, but there is extensive debate about the computations and representations underlying perceived lightness. One view asserts that the visual system explicitly separates surface reflectance from the prevailing illumination and atmospheric conditions in which it is embedded, generating layered image representations. Some recent theory has challenged this view and asserted that the human visual system derives surface lightness without explicitly segmenting images into multiple layers. Here we present new lightness illusions--the largest reported to date--that unequivocally demonstrate the effect that layered image representations can have in lightness perception. We show that the computations that underlie the decomposition of luminance into multiple layers under conditions of transparency can induce dramatic lightness illusions, causing identical texture patches to appear either black or white. These results indicate that mechanisms involved in decomposing images into layered representations can play a decisive role in the perception of surface lightness. 相似文献
113.
Loftus B Anderson I Davies R Alsmark UC Samuelson J Amedeo P Roncaglia P Berriman M Hirt RP Mann BJ Nozaki T Suh B Pop M Duchene M Ackers J Tannich E Leippe M Hofer M Bruchhaus I Willhoeft U Bhattacharya A Chillingworth T Churcher C Hance Z Harris B Harris D Jagels K Moule S Mungall K Ormond D Squares R Whitehead S Quail MA Rabbinowitsch E Norbertczak H Price C Wang Z Guillén N Gilchrist C Stroup SE Bhattacharya S Lohia A Foster PG Sicheritz-Ponten T Weber C Singh U Mukherjee C El-Sayed NM 《Nature》2005,433(7028):865-868
Entamoeba histolytica is an intestinal parasite and the causative agent of amoebiasis, which is a significant source of morbidity and mortality in developing countries. Here we present the genome of E. histolytica, which reveals a variety of metabolic adaptations shared with two other amitochondrial protist pathogens: Giardia lamblia and Trichomonas vaginalis. These adaptations include reduction or elimination of most mitochondrial metabolic pathways and the use of oxidative stress enzymes generally associated with anaerobic prokaryotes. Phylogenomic analysis identifies evidence for lateral gene transfer of bacterial genes into the E. histolytica genome, the effects of which centre on expanding aspects of E. histolytica's metabolic repertoire. The presence of these genes and the potential for novel metabolic pathways in E. histolytica may allow for the development of new chemotherapeutic agents. The genome encodes a large number of novel receptor kinases and contains expansions of a variety of gene families, including those associated with virulence. Additional genome features include an abundance of tandemly repeated transfer-RNA-containing arrays, which may have a structural function in the genome. Analysis of the genome provides new insights into the workings and genome evolution of a major human pathogen. 相似文献
114.
115.
Hexadecane decay by methanogenesis 总被引:12,自引:0,他引:12
116.
A small-molecule nitroimidazopyran drug candidate for the treatment of tuberculosis 总被引:32,自引:0,他引:32
Stover CK Warrener P VanDevanter DR Sherman DR Arain TM Langhorne MH Anderson SW Towell JA Yuan Y McMurray DN Kreiswirth BN Barry CE Baker WR 《Nature》2000,405(6789):962-966
Mycobacterium tuberculosis, which causes tuberculosis, is the greatest single infectious cause of mortality worldwide, killing roughly two million people annually. Estimates indicate that one-third of the world population is infected with latent M. tuberculosis. The synergy between tuberculosis and the AIDS epidemic, and the surge of multidrug-resistant clinical isolates of M. tuberculosis have reaffirmed tuberculosis as a primary public health threat. However, new antitubercular drugs with new mechanisms of action have not been developed in over thirty years. Here we report a series of compounds containing a nitroimidazopyran nucleus that possess antitubercular activity. After activation by a mechanism dependent on M. tuberculosis F420 cofactor, nitroimidazopyrans inhibited the synthesis of protein and cell wall lipid. In contrast to current antitubercular drugs, nitroimidazopyrans exhibited bactericidal activity against both replicating and static M. tuberculosis. Lead compound PA-824 showed potent bactericidal activity against multidrugresistant M. tuberculosis and promising oral activity in animal infection models. We conclude that nitroimidazopyrans offer the practical qualities of a small molecule with the potential for the treatment of tuberculosis. 相似文献
117.
R H Anderson 《Experientia》1971,27(9):1063-1064
118.
Primary structure, gene organization and polypeptide expression of poliovirus RNA 总被引:217,自引:0,他引:217
N Kitamura B L Semler P G Rothberg G R Larsen C J Adler A J Dorner E A Emini R Hanecak J J Lee S van der Werf C W Anderson E Wimmer 《Nature》1981,291(5816):547-553
The primary structure of the poliovirus genome has been determined. The RNA molecule is 7,433 nucleotides long, polyadenylated at the 3' terminus, and covalently linked to a small protein (VPg) at the 5' terminus. An open reading frame of 2,207 consecutive triplets spans over 89% of the nucleotide sequence and codes for the viral polyprotein NCVPOO. Twelve viral polypeptides have been mapped by amino acid sequence analysis and were found to be proteolytic cleavage products of the polyprotein, cleavages occurring predominantly at Gln-Gly pairs. 相似文献
119.
C. J. Louis G. C. Kenny R. D. Anderson 《Cellular and molecular life sciences : CMLS》1970,26(7):756-757
Zusammenfassung Die Verteilung von aus 5-Hydroxy-Tryptophan entstandenem Serotonin in der Zirbeldrüse von Affen wird beschrieben. 相似文献