tailieunhanh - Báo cáo sinh học: " Comparative genomics of Bacillus thuringiensis phage 0305φ8-36: defining patterns of descent in a novel ancient phage lineage"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Comparative genomics of Bacillus thuringiensis phage 0305φ8-36: defining patterns of descent in a novel ancient phage lineage | Virology Journal BioMed Central Research Open Access Comparative genomics of Bacillus thuringiensis phage 0305Ộ8-36 defining patterns of descent in a novel ancient phage lineage Stephen C Hardies Julie A Thomas and Philip Serwer Address Department of Biochemistry University of Texas Health Science Center at San Antonio 7703 Floyd Curl Drive San Antonio Texas 78229-3900 USA Email Stephen C Hardies - hardies@ Julie A Thomas - thomasj4@ Philip Serwer - serwer@ Corresponding author Published 5 October 2007 Received 5 June 2007 Accepted 5 October 2007 Virology Journal 2007 4 97 doi 1743-422X-4-97 This article is available from http content 4 1 97 2007 Hardies et al 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 The recently sequenced 218 kb genome of morphologically atypical Bacillus thuringiensis phage 0305Ộ8-36 exhibited only limited detectable homology to known bacteriophages. The only known relative of this phage is a string of phage-like genes called BtI1 in the chromosome of B. thuringiensis israelensis. The high degree of divergence and novelty of phage genomes pose challenges in how to describe the phage from its genomic sequences. Results Phage 0305Ộ8-36 and BtI1 are estimated to have diverged - billion years ago. Positionally biased Blast searches aligned 30 homologous structure or morphogenesis genes between 0305Ộ8-36 and BtI1 that have maintained the same gene order. Functional clustering of the genes helped identify additional gene functions. A conserved long tape measure gene indicates that a long tail is an evolutionarily stable property of this phage lineage. An unusual form of the tail chaperonin system split to two genes was