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951.
Complete sequencing of 62 mitochondrial DNAs (mtDNAs) belonging (or very closely related) to haplogroup H revealed that this mtDNA haplogroup--by far the most common in Europe--is subdivided into numerous subhaplogroups, with at least 15 of them (H1-H15) identifiable by characteristic mutations. All the haplogroup H mtDNAs found in 5,743 subjects from 43 populations were then screened for diagnostic markers of subhaplogroups H1 and H3. This survey showed that both subhaplogroups display frequency peaks, centered in Iberia and surrounding areas, with distributions declining toward the northeast and southeast--a pattern extremely similar to that previously reported for mtDNA haplogroup V. Furthermore, the coalescence ages of H1 and H3 (~11,000 years) are close to that previously reported for V. These findings have major implications for the origin of Europeans, since they attest that the Franco-Cantabrian refuge area was indeed the source of late-glacial expansions of hunter-gatherers that repopulated much of Central and Northern Europe from ~15,000 years ago. This has also some implications for disease studies. For instance, the high occurrence of H1 and H3 in Iberia led us to re-evaluate the haplogroup distribution in 50 Spanish families affected by nonsyndromic sensorineural deafness due to the A1555G mutation. The survey revealed that the previously reported excess of H among these families is caused entirely by H3 and is due to a major, probably nonrecent, founder event.  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - Hairy roots (HR) are a promising plant tissue-based platform for the production of biopharmaceuticals as the secretion of recombinant proteins in the...  相似文献   
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This study describes the identification and structural characterization of Sus scrofa statherin. HPLC–electrospray ionization mass spectrometry analysis on pig parotid secretory granule extracts evidenced a peptide with a molecular mass value of 5381.1 ± 0.6 Da and its truncated form, devoid of the C‐terminal Ala residue, with a molecular mass value of 5310.1 ± 0.6 Da. The complete sequence of pig statherin gene was determined by sequencing the full‐length cDNA obtained by rapid amplification of cDNA ends. The gene is 549 base pairs long and contains an open reading frame of 185 nucleotides, encoding a 42‐amino acid secretory polypeptide with a signal peptide of 19 residues. This sequence presents some typical features of the four statherins characterized till now, showing the highest degree of amino acid identity with bovine (57%) and human statherin (39%). Pig statherin is mono‐phoshorylated on Ser‐3, while primate statherins already characterized are di‐phosphorylated on Ser‐2 and Ser‐3. This difference, probably connected to the Asp‐4 → Glu substitution, suggests the involvement of the Golgi‐casein kinase, which strictly recognizes the SX(E/pS) consensus sequence. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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Background  

The modular approach to analysis of genetically modified organisms (GMOs) relies on the independence of the modules combined (i.e. DNA extraction and GM quantification). The validity of this assumption has to be proved on the basis of specific performance criteria.  相似文献   
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Biogas is a renewable energy resource produced during the anaerobic digestion of various organic substrates. A wide community of microorganisms is involved, including methanogens. These Archaea are the biologic key to the process because they accomplish the methane-forming reaction. Despite its crucial role, the microbiome inside the digester is poorly understood. The aim of this work is to develop bioindicators of efficiency for the anaerobic process through the quantification and characterisation of the methanogens and sulphate-reducing bacteria. From a full-scale digester fed with organic wastes, 31 samples were collected. Temperature, pH, acidity, alkalinity and biogas quantity and quality were monitored over time. The methanogens were detected from the samples both in total and as belonging to different taxa units. These evaluations, by real-time quantitative PCR (RT-qPCR) methods, produced valuable results for Methanosarcina, Methanosaeta, Methanocorpusculaceae and sulphate-reducing bacteria. Methanosarcina was the most abundant family, followed by Methanocorpusculaceae and then Methanosaeta. The methanogen taxa are significantly and directly correlated with each other (p?<?0.05). Methanosaeta and Methanocorpusculaceae are present in significantly different amounts at different temperatures. While Methanosaeta levels also change when the organic load increases (t test, p?<?0.05), Methanosarcina is more tolerant, and its levels are quite constant. Methanosarcina and Methanosaeta are proposed to be bioindicators of the stability of the process (the first) and of susceptibility (the second) to detect early sufferance conditions in the digester. These methods will be useful in the control and optimisation of an eco-friendly waste-to-energy system.  相似文献   
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