Chapter9 Microbial taxonomy Three separate but interrelated parts 1. Classification: the arrangement of organisms into groups or taxa based on mutual similarity or evolutionary relatedness 2. Nomenclature: the branch of taxonomy concerned with the assignment of names to taxonomic groups in agreement with published rules 3. Identification: the practical side of taxonomy, the process of determining that a particular isolate belongs to a recognized taxon
Three separate but interrelated parts: 1. Classification: the arrangement of organisms into groups or taxa based on mutual similarity or evolutionary relatedness. 2. Nomenclature: the branch of taxonomy concerned with the assignment of names to taxonomic groups in agreement with published rules. 3. Identification: the practical side of taxonomy, the process of determining that a particular isolate belongs to a recognized taxon. Chapter9 Microbial taxonomy
Taxonomy is important for several reasons 1. It allows us to organize huge amounts of knowledge about organisms Allows us to make predictions and frame hypotheses for further research based on knowledge of similar organisms It places microorganisms in meaningful, useful groups with precise names so that microbiologists can work with them and communicate efficientl 4. Identification of microorganisms accurately
Taxonomy is important for several reasons 1. It allows us to organize huge amounts of knowledge about organisms 2. Allows us to make predictions and frame hypotheses for further research based on knowledge of similar organisms. 3. It places microorganisms in meaningful, useful groups with precise names so that microbiologists can work with them and communicate efficiently. 4. Identification of microorganisms accurately
y Strain: onesingleisolateorline Type: sub-setofspecies /⑤明明同加(si3 y Genus: related species Famiy: relatedgenera Order class, phylum domain
Taxomomic ranks ✓ Strain: one single isolate or line ✓ Type: sub-set of species ✓ Species: related strains ✓ Genus: related species ✓ Family: related genera ✓ Order; class; phylum; domain
Related concepts aH a collection of strains that have a similar G+C composotion and 70% or greater similarity as judged by DNA hybridization experiments o variant procaryotic strains characterized Dy biochemical or physiological differences roars differ morphologically eroa have distinctive antigenIc properties nesta it is usually one of the first strains studied and often is more fully characterized than other strains
Related concepts A species: a collection of strains that have a similar G+C composotion and 70% or greater similarity as judged by DNA hybridization experiments. A biovars: variant procaryotic strains characterized by biochemical or physiological differences. Morphovars: differ morphologically Serovars: have distinctive antigenic properties Type strain: it is usually one of the first strains studied and often is more fully characterized than other strains
Classification systems Phenetic classification: one that groups organisms together based on the mutual similarity of their phenotypic characteristics Comparing as many attributes as possible umerical taxonomy: computers may be used to analyze data for the production of phenetic classification Information about the properties of organisms converted into a form suitable for numerical analysis and then compared by means of a computer Phylogenetic classification: based on evolutionary relationships rather than general resemblance defficult because of the lack of a good fossil record Comparision of genetic material and gene products
Classification systems Phenetic classification: one that groups organisms together based on the mutual similarity of their phenotypic characteristics. Comparing as many attributes as possible. Numerical taxonomy: computers may be used to analyze data for the production of phenetic classification. Information about the properties of organisms is converted into a form suitable for numerical analysis and then compared by means of a computer. Phylogenetic classification: based on evolutionary relationships rather than general resemblance. defficult because of the lack of a good fossil record. Comparision of genetic material and gene products