Meet Inspiring Speakers and Experts at our 3000+ Global Conference Series LLC LTD Events with over 1000+ Conferences, 1000+ Symposiums
and 1000+ Workshops on Medical, Pharma, Engineering, Science, Technology and Business.

Explore and learn more about Conference Series LLC LTD : World’s leading Event Organizer


4th International Conference on Applied Microbiology and Beneficial Microbes

Tokyo, Japan

Shu-Lin Liu

Shu-Lin Liu

Harbin Medical University, China

Title: Defining natural species of bacteria by a common yardstick: Universal genomic parameter to delineate bacteria into discrete phylogenetic clusters


Biography: Shu-Lin Liu


Bacteria are classified, like higher organisms into species but the current taxonomic species contain bacteria of enormous phylogenetic diversity, causing serious confusions in medical practice and other fields. Therefore, a common yardstick is badly needed for universally defining bacterial species by using a parameter that produces discrete rather than continual data to reveal clear-cut distinctions among the species. Using Salmonella as the primary model to search for such delineating genomic parameters, we found that members of a monophyletic bacterial grouping equivalent to natural species have a high percentage of their common genes sharing identical nucleotide sequences. The percentage windows are mostly broad: >70% for members within a species and <10% for bacteria between species. Similarly, broad percentage windows were also seen in Streptomyces; we propose percentages (<70%) to reflect genetic boundaries and exclude bacteria from a species. The clear-cut nature of such percentages makes them suitable as a common yardstick to define natural bacterial species. The broad percentage windows could be interpreted as the results of non-overlapping gene pools; bacteria of the same gene pool can purge less adapted members once they acquire beneficial traits, but they cannot do that across different gene pools.