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71.
Chelliah Edward Raja Kolandaswamy Anbazhagan Govindan Sadasivam Selvam 《World journal of microbiology & biotechnology》2006,22(6):577-585
Summary The use of microorganisms to remove heavy metals from industrial effluent is an area of extensive research and development.
Attempts have been made to isolate and characterize metal-resistant microorganisms from treated oil mill industry effluent
wastewater samples. The metal-resistant organisms that showed values of minimum inhibitory concentration towards metals (Cd,
Cr, Ni and Pb) ranging from 100 to 800 ppm level were screened. A potent metal-resistant organism, isolate BC15 from the wastewater
samples was tentatively identified as Pseudomonas sp. Detailed analysis of morphological, biochemical and 16S rDNA sequence of the isolate revealed that it is closely related
to Pseudomonas aeruginosa (94%). Pseudomonas BC15 was capable of absorbing 93% Ni, 65% Pb, 50% Cd and 30% Cr within 48 h from the medium containing 100 mg of each heavy
metal per liter. The multiple metal tolerance of this strain was also associated with resistance to antibiotics such as ampicillin,
tetracycline, chloramphenicol, erythromycin, kanamycin and streptomycin. 相似文献
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73.
Chen J Anderson JB DeWeese-Scott C Fedorova ND Geer LY He S Hurwitz DI Jackson JD Jacobs AR Lanczycki CJ Liebert CA Liu C Madej T Marchler-Bauer A Marchler GH Mazumder R Nikolskaya AN Rao BS Panchenko AR Shoemaker BA Simonyan V Song JS Thiessen PA Vasudevan S Wang Y Yamashita RA Yin JJ Bryant SH 《Nucleic acids research》2003,31(1):474-477
Three-dimensional structures are now known within most protein families and it is likely, when searching a sequence database, that one will identify a homolog of known structure. The goal of Entrez's 3D-structure database is to make structure information and the functional annotation it can provide easily accessible to molecular biologists. To this end, Entrez's search engine provides several powerful features: (i) links between databases, for example between a protein's sequence and structure; (ii) pre-computed sequence and structure neighbors; and (iii) structure and sequence/structure alignment visualization. Here, we focus on a new feature of Entrez's Molecular Modeling Database (MMDB): Graphical summaries of the biological annotation available for each 3D structure, based on the results of automated comparative analysis. MMDB is available at: http://www.ncbi.nlm.nih.gov/Entrez/structure.html. 相似文献
74.
Huzefa A. Raja Noemi D. Paguigan Jacques Fournier Nicholas H. Oberlies 《Mycological Progress》2017,16(5):535-552
Two new species of freshwater ascomycetes belonging to the genus Lindgomyces (Pleosporales, Dothideomycetes) are described and illustrated from submerged wood in North Carolina, USA. Lindgomyces carolinensis is characterized by immersed to erumpent ascomata, fissitunicate broadly cylindrical to clavate asci, and fusiform ascospores with acute ends surrounded by a large, fusiform gelatinous sheath. Lindgomyces cigarospora morphologically differs from L. carolinensis in that its ascospores are fusiform to cylindrical with rounded ends, without a large fusiform gelatinous sheath. These two new species nest in the family Lindgomycetaceae based on analyses of combined SSU and LSU rDNA sequence data. Phylogenetic analyses using ITS sequence data support the establishment of the new taxa as separate species within Lindgomyces. In addition to the new species, we report new ITS sequence data for L. cinctosporus and L. griseosporus from France, and L. ingoldianus from North Carolina, USA. We report a video exhibiting fissitunicate ascus dehiscence in L. carolinensis showing ascospore discharge and unraveling of the gelatinous sheath in real time. Chemical analysis of the organic extracts of L. carolinensis and L. cigarospora resulted in two known cyclodepsipeptides, Sch 378161 and Sch 217048. The in situ spatial mapping of these secondary metabolites on fungal cultures indicates the presence of both compounds on the surface of mycelia, as well as being exuded into the surrounding agar. 相似文献
75.
2’-Methoxy-6-methylflavone (2’MeO6MF) is an anxiolytic flavonoid which has been shown to display GABAA receptor (GABAAR) β2/3-subunit selectivity, a pharmacological profile similar to that of the general anaesthetic etomidate. Electrophysiological studies suggest that the full agonist action of 2’MeO6MF at α2β3γ2L GABAARs may mediate the flavonoid’s in vivo effects. However, we found variations in the relative efficacy of 2’MeO6MF (2’MeO6MF-elicited current responses normalised to the maximal GABA response) at α2β3γ2L GABAARs due to the presence of mixed receptor populations. To understand which receptor subpopulation(s) underlie the variations observed, we conducted a systematic investigation of 2’MeO6MF activity at all receptor combinations that could theoretically form (α2, β3, γ2L, α2β3, α2γ2L, β3γ2L and α2β3γ2L) in Xenopus oocytes using the two-electrode voltage clamp technique. We found that 2’MeO6MF activated non-α-containing β3γ2L receptors. In an attempt to establish the optimal conditions to express a uniform population of these receptors, we found that varying the relative amounts of β3:γ2L subunit mRNAs resulted in differences in the level of constitutive activity, the GABA concentration-response relationships, and the relative efficacy of 2’MeO6MF activation. Like 2’MeO6MF, general anaesthetics such as etomidate and propofol also showed distinct levels of relative efficacy across different injection ratios. Based on these results, we infer that β3γ2L receptors may form with different subunit stoichiometries, resulting in the complex pharmacology observed across different injection ratios. Moreover, the discovery that GABA and etomidate have direct actions at the α-lacking β3γ2L receptors raises questions about the structural requirements for their respective binding sites at GABAARs. 相似文献
76.
Mark Manzano Eleonora Forte Archana N. Raja Matthew J. Schipma Eva Gottwein 《RNA (New York, N.Y.)》2015,21(9):1606-1620
Sequence heterogeneity at the ends of mature microRNAs (miRNAs) is well documented, but its effects on miRNA function are largely unexplored. Here we studied the impact of miRNA 5′-heterogeneity, which affects the seed region critical for target recognition. Using the example of miR-142-3p, an emerging regulator of the hematopoietic lineage in vertebrates, we show that naturally coexpressed 5′-variants (5′-isomiRs) can recognize largely distinct sets of binding sites. Despite this, both miR-142-3p isomiRs regulate exclusive and shared targets involved in actin dynamics. Thus, 5′-heterogeneity can substantially broaden and enhance regulation of one pathway. Other 5′-isomiRs, in contrast, recognize largely overlapping sets of binding sites. This is exemplified by two herpesviral 5′-isomiRs that selectively mimic one of the miR-142-3p 5′-isomiRs. We hypothesize that other cellular and viral 5′-isomiRs can similarly be grouped into those with divergent or convergent target repertoires, based on 5′-sequence features. Taken together, our results provide a detailed characterization of target recognition by miR-142-3p and its 5′-isomiR-specific viral mimic. We furthermore demonstrate that miRNA 5′-end variation leads to differential targeting and can thus broaden the target range of miRNAs. 相似文献
77.
Translational silencing of ceruloplasmin requires the essential elements of mRNA circularization: poly(A) tail, poly(A)-binding protein, and eukaryotic translation initiation factor 4G 总被引:1,自引:0,他引:1 下载免费PDF全文
Mazumder B Seshadri V Imataka H Sonenberg N Fox PL 《Molecular and cellular biology》2001,21(19):6440-6449
78.
Hill C Soares P Mormina M Macaulay V Meehan W Blackburn J Clarke D Raja JM Ismail P Bulbeck D Oppenheimer S Richards M 《Molecular biology and evolution》2006,23(12):2480-2491
Studying the genetic history of the Orang Asli of Peninsular Malaysia can provide crucial clues to the peopling of Southeast Asia as a whole. We have analyzed mitochondrial DNA (mtDNAs) control-region and coding-region markers in 447 mtDNAs from the region, including 260 Orang Asli, representative of each of the traditional groupings, the Semang, the Senoi, and the Aboriginal Malays, allowing us to test hypotheses about their origins. All of the Orang Asli groups have undergone high levels of genetic drift, but phylogeographic traces nevertheless remain of the ancestry of their maternal lineages. The Semang have a deep ancestry within the Malay Peninsula, dating to the initial settlement from Africa >50,000 years ago. The Senoi appear to be a composite group, with approximately half of the maternal lineages tracing back to the ancestors of the Semang and about half to Indochina. This is in agreement with the suggestion that they represent the descendants of early Austroasiatic speaking agriculturalists, who brought both their language and their technology to the southern part of the peninsula approximately 4,000 years ago and coalesced with the indigenous population. The Aboriginal Malays are more diverse, and although they show some connections with island Southeast Asia, as expected, they also harbor haplogroups that are either novel or rare elsewhere. Contrary to expectations, complete mtDNA genome sequences from one of these, R9b, suggest an ancestry in Indochina around the time of the Last Glacial Maximum, followed by an early-Holocene dispersal through the Malay Peninsula into island Southeast Asia. 相似文献
79.
80.
B. Raja Rao K. G. Janardan D. J. Schaeffer 《Biometrical journal. Biometrische Zeitschrift》1984,26(8):941-946
The distribution of the time T for the occurrence of the rth event is derived in a linear function Poisson process, which belongs to a recently introduced family of distributions (JANARDAN and RAO, 1981), called Lagrangian distributions of the second kind (LD2). In analogy with the ordinary Poisson process, the distribution of the random variable T has been termed the Lagrangian Gamma distribution of the second kind (LG2); several of its properties and special cases are studied. The frequency function is graphed for some parameter values. 相似文献