A virus strain, showing cytopathic effect in BHK-21 cell, was isolated from swine brains in Shaanxi Province, China, in 2007. The isolate was confirmed as Japanese encephalitis virus (JEV) by immunofluorescence ass...A virus strain, showing cytopathic effect in BHK-21 cell, was isolated from swine brains in Shaanxi Province, China, in 2007. The isolate was confirmed as Japanese encephalitis virus (JEV) by immunofluorescence assay (IFA) and reverse transcription polymerase chain reaction (RT-PCR), and named SXBJ07. The complete nueleotide and deduced amino acid sequences of the JEV strain SXBJ07 were determined. Its single open reading frame has a total of 3 432 amino acid residues. An extensive E gene based phylogenetic analysis was performed, the result showed that SXBJ07 strain belongs to genotype I. Comparison of the SXBJ07 genomic sequence with those of the 24 fully sequenced JEV strains in published databases showed nucleotide homology ranging from 99.0 to 83.7%; amino acid homology ranged from 99.8 to 94.8%. Compared SXBJ07 with SA14-14-2 strain, the current live vaccine strain in China, the homology of amino acid in envelope gene was 97.0%; and there were amino acid substitutions in 13 sites of the active domains of E protein (E1-E411).展开更多
Reversals, transpositions and transreversals are common events in genome rearrangement. The genome rearrangement sorting problem is to transform one genome into another using the minimum number of given rearrangement ...Reversals, transpositions and transreversals are common events in genome rearrangement. The genome rearrangement sorting problem is to transform one genome into another using the minimum number of given rearrangement operations. An integer permutation is used to represent a genome in many cases. It can be divided into disjoint strips with each strip denoting a block of consecutive integers. A singleton is a strip of one integer. And the genome rearrange- ment problem turns into the problem of sorting a permutation into the identity permutation equivalently. Hannenhalli and Pevzner designed a polynomial time algorithm for the unsigned reversal sorting problem on those permutations with O(logn) singletons. In this paper, first we describe one case in which Hannenhalli and Pevzner's algorithm may fail and propose a corrected approach. In addition, we propose a (1 + ε)-approximation algorithm for sorting unsigned permutations with O(log n) singletons by reversals of weight 1 and transpositions/transreversals of weight 2.展开更多
基金supported by the National Natural Science Foundation of China (30771067)
文摘A virus strain, showing cytopathic effect in BHK-21 cell, was isolated from swine brains in Shaanxi Province, China, in 2007. The isolate was confirmed as Japanese encephalitis virus (JEV) by immunofluorescence assay (IFA) and reverse transcription polymerase chain reaction (RT-PCR), and named SXBJ07. The complete nueleotide and deduced amino acid sequences of the JEV strain SXBJ07 were determined. Its single open reading frame has a total of 3 432 amino acid residues. An extensive E gene based phylogenetic analysis was performed, the result showed that SXBJ07 strain belongs to genotype I. Comparison of the SXBJ07 genomic sequence with those of the 24 fully sequenced JEV strains in published databases showed nucleotide homology ranging from 99.0 to 83.7%; amino acid homology ranged from 99.8 to 94.8%. Compared SXBJ07 with SA14-14-2 strain, the current live vaccine strain in China, the homology of amino acid in envelope gene was 97.0%; and there were amino acid substitutions in 13 sites of the active domains of E protein (E1-E411).
基金Supported by the National Natural Science Foundation of China under Grant No.60970003the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No.20090131110009the Key Science-Technology Project of Shandong Province of China under Grant No.2006GG2201005
文摘Reversals, transpositions and transreversals are common events in genome rearrangement. The genome rearrangement sorting problem is to transform one genome into another using the minimum number of given rearrangement operations. An integer permutation is used to represent a genome in many cases. It can be divided into disjoint strips with each strip denoting a block of consecutive integers. A singleton is a strip of one integer. And the genome rearrange- ment problem turns into the problem of sorting a permutation into the identity permutation equivalently. Hannenhalli and Pevzner designed a polynomial time algorithm for the unsigned reversal sorting problem on those permutations with O(logn) singletons. In this paper, first we describe one case in which Hannenhalli and Pevzner's algorithm may fail and propose a corrected approach. In addition, we propose a (1 + ε)-approximation algorithm for sorting unsigned permutations with O(log n) singletons by reversals of weight 1 and transpositions/transreversals of weight 2.