Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: The use of genomic signature distance between bacteriophages and their hosts displays evolutionary relationships and phage growth cycle determination | Deschavanne et al. Virology Journal 2010 7 163 http content 7 1 163 VIROLOGY JOURNAL RESEARCH Open Access The use of genomic signature distance between bacteriophages and their hosts displays evolutionary relationships and phage growth cycle determination Patrick Deschavanne 1 Michael S DuBow2 Christophe Regeard2 Abstract Background Bacteriophage classification is mainly based on morphological traits and genome characteristics combined with host information and in some cases on phage growth lifestyle. A lack of molecular tools can impede more precise studies on phylogenetic relationships or even a taxonomic classification. The use of methods to analyze genome sequences without the requirement for homology has allowed advances in classification. Results Here we proposed to use genome sequence signature to characterize bacteriophages and to compare them to their host genome signature in order to obtain host-phage relationships and information on their lifestyle. We analyze the host-phage relationships in the four most representative groups of Caudoviridae the dsDNA group of phages. We demonstrate that the use of phage genomic signature and its comparison with that of the host allows a grouping of phages and is also able to predict the host-phage relationships lytic vs. temperate . Conclusions We can thus condense in relatively simple figures this phage information dispersed over many publications. Background Bacteriophages are the most abundant biological entities on Earth and their total population is estimated at approximately 1031 particles on earth 1 . In comparison with the estimated 1030 bacterial cells in the biosphere 2 there are thus 10 virus particles for each putative host 3 4 . In aquatic or terrestrial samples 106 to 107 viral particles per milliliter of water or gram of soil are regularly reported. Moreover these viruses are highly dynamic leading to approximately 1023 infections per second 5 . The study of phage diversity is crucial .
