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排序方式: 共有130条查询结果,搜索用时 171 毫秒
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Schmutz J Wheeler J Grimwood J Dickson M Yang J Caoile C Bajorek E Black S Chan YM Denys M Escobar J Flowers D Fotopulos D Garcia C Gomez M Gonzales E Haydu L Lopez F Ramirez L Retterer J Rodriguez A Rogers S Salazar A Tsai M Myers RM 《Nature》2004,429(6990):365-368
As the final sequencing of the human genome has now been completed, we present the results of the largest examination of the quality of the finished DNA sequence. The completed study covers the major contributing sequencing centres and is based on a rigorous combination of laboratory experiments and computational analysis. 相似文献
65.
The DNA sequence and comparative analysis of human chromosome 5 总被引:1,自引:0,他引:1
Schmutz J Martin J Terry A Couronne O Grimwood J Lowry S Gordon LA Scott D Xie G Huang W Hellsten U Tran-Gyamfi M She X Prabhakar S Aerts A Altherr M Bajorek E Black S Branscomb E Caoile C Challacombe JF Chan YM Denys M Detter JC Escobar J Flowers D Fotopulos D Glavina T Gomez M Gonzales E Goodstein D Grigoriev I Groza M Hammon N Hawkins T Haydu L Israni S Jett J Kadner K Kimball H Kobayashi A Lopez F Lou Y Martinez D Medina C Morgan J Nandkeshwar R Noonan JP Pitluck S Pollard M Predki P 《Nature》2004,431(7006):268-274
Chromosome 5 is one of the largest human chromosomes and contains numerous intrachromosomal duplications, yet it has one of the lowest gene densities. This is partially explained by numerous gene-poor regions that display a remarkable degree of noncoding conservation with non-mammalian vertebrates, suggesting that they are functionally constrained. In total, we compiled 177.7 million base pairs of highly accurate finished sequence containing 923 manually curated protein-coding genes including the protocadherin and interleukin gene families. We also completely sequenced versions of the large chromosome-5-specific internal duplications. These duplications are very recent evolutionary events and probably have a mechanistic role in human physiological variation, as deletions in these regions are the cause of debilitating disorders including spinal muscular atrophy. 相似文献
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Sánchez-Hidalgo M Montalbán-López M Cebrián R Valdivia E Martínez-Bueno M Maqueda M 《Cellular and molecular life sciences : CMLS》2011,68(17):2845-2857
Bacteriocin AS-48 is an intriguing molecule because of its unique structural characteristics, genetic regulation, broad activity
spectrum, and potential biotechnological applications. It was the first reported circular bacteriocin and has been undoubtedly
the best characterized for the last 25 years. Thus, AS-48 is the prototype of circular bacteriocins (class IV), for which
the structure and genetic regulation have been elucidated. This review discusses the state-of-the-art in genetic engineering
with regard to this circular protein, with the use of site-directed mutagenesis and circular permutation. Mutagenesis studies
have been used to unravel the role of (a) different residues in the biological activity, underlining the relevance of several
residues involved in membrane interaction and the low correlation between stability and activity and (b) three amino acids
involved in maturation, providing information on the specificity of the leader peptidase and the circularization process itself.
To investigate the role of circularity in the stability and biological properties of the enterocin AS-48, two different ways
of linearization have been attempted: in vitro by limited proteolysis experiments and in vivo by circular permutation in the
structural gene as-48A. The results summarized here show the significance of circularization on the secondary structure, potency and, especially,
the stability of AS-48 and point as well to a putative role of the leader peptide as a protecting moiety in the pre-proprotein.
Taken all together, the data available on circular bacteriocins support the idea that AS-48 has been engineered by nature
to make a remarkably active and stable protein with a broad spectrum of activity. 相似文献
68.
Witt H Sahin-Tóth M Landt O Chen JM Kähne T Drenth JP Kukor Z Szepessy E Halangk W Dahm S Rohde K Schulz HU Le Maréchal C Akar N Ammann RW Truninger K Bargetzi M Bhatia E Castellani C Cavestro GM Cerny M Destro-Bisol G Spedini G Eiberg H Jansen JB Koudova M Rausova E Macek M Malats N Real FX Menzel HJ Moral P Galavotti R Pignatti PF Rickards O Spicak J Zarnescu NO Böck W Gress TM Friess H Ockenga J Schmidt H Pfützer R Löhr M Simon P Weiss FU Lerch MM Teich N Keim V Berg T Wiedenmann B Luck W 《Nature genetics》2006,38(6):668-673
Chronic pancreatitis is a common inflammatory disease of the pancreas. Mutations in the genes encoding cationic trypsinogen (PRSS1) and the pancreatic secretory trypsin inhibitor (SPINK1) are associated with chronic pancreatitis. Because increased proteolytic activity owing to mutated PRSS1 enhances the risk for chronic pancreatitis, mutations in the gene encoding anionic trypsinogen (PRSS2) may also predispose to disease. Here we analyzed PRSS2 in individuals with chronic pancreatitis and controls and found, to our surprise, that a variant of codon 191 (G191R) is overrepresented in control subjects: G191R was present in 220/6,459 (3.4%) controls but in only 32/2,466 (1.3%) affected individuals (odds ratio 0.37; P = 1.1 x 10(-8)). Upon activation by enterokinase or trypsin, purified recombinant G191R protein showed a complete loss of trypsin activity owing to the introduction of a new tryptic cleavage site that renders the enzyme hypersensitive to autocatalytic proteolysis. In conclusion, the G191R variant of PRSS2 mitigates intrapancreatic trypsin activity and thereby protects against chronic pancreatitis. 相似文献
69.
Williams RB Cotsapas CJ Cowley MJ Chan E Nott DJ Little PF 《Nature genetics》2006,38(8):855-6; author reply 856-9
70.
Friesen TL Stukenbrock EH Liu Z Meinhardt S Ling H Faris JD Rasmussen JB Solomon PS McDonald BA Oliver RP 《Nature genetics》2006,38(8):953-956
New diseases of humans, animals and plants emerge regularly. Enhanced virulence on a new host can be facilitated by the acquisition of novel virulence factors. Interspecific gene transfer is known to be a source of such virulence factors in bacterial pathogens (often manifested as pathogenicity islands in the recipient organism) and it has been speculated that interspecific transfer of virulence factors may occur in fungal pathogens. Until now, no direct support has been available for this hypothesis. Here we present evidence that a gene encoding a critical virulence factor was transferred from one species of fungal pathogen to another. This gene transfer probably occurred just before 1941, creating a pathogen population with significantly enhanced virulence and leading to the emergence of a new damaging disease of wheat. 相似文献