tailieunhanh - báo cáo hóa học:" Host-derived pathogenicity islands in poxviruses"

Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí sinh học đề tài : Host-derived pathogenicity islands in poxviruses | Virology Journal BioMed Central Research Host-derived pathogenicity islands in poxviruses Melissa Da Silva and Chris Upton Address Department of Biochemistry and Microbiology University of Victoria Victoria Canada Email Melissa Da Silva - mdasilva@ Chris Upton - cupton@ Corresponding author Open Access Published II April 2005 Received II February 2005 Accepted 1 1 April 2005 Virology Journal 2005 2 30 doi 186 1 743-422X-2-30 This article is available from http content 2 1 30 2005 Da Silva and Upton licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background Poxviruses are important both as pathogens and as vaccine vectors. Poxvirus genomes 150-350 kb consist of a single linear dsDNA molecule the two polynucleotide strands are joined by short hairpin loops. The genomes encode highly conserved proteins required for DNA replication and mRNA transcription as well as a variable set of virulence factors transcription takes place within the cytoplasm of the host cell. We are interested in evolution of poxvirus genomes and especially how these viruses acquire host-derived genes that are believed to function as virulence factors. Results Using a variety of bioinformatics tools we have identified regions in poxvirus genomes that have unusual nucleotide composition higher or lower than average A T content compared to the genome as a whole such regions may be several kilobases in length and contain a number of genes. Regions with unusual nucleotide composition may represent genes that have been recently acquired from the host genome. The study of these genomic regions with unusual nucleotide content will help elucidate evolutionary processes in poxviruses. Conclusion We have found that .