
Full text loading...
Category: Bacterial Pathogenesis
Taxonomy of the Helicobacter Genus, Page 1 of 2
< Previous page | Next page > /docserver/preview/fulltext/10.1128/9781555818005/9781555812133_Chap05-1.gif /docserver/preview/fulltext/10.1128/9781555818005/9781555812133_Chap05-2.gifAbstract:
This chapter describes the taxonomic characteristics of the Helicobacter genus and discusses methods used to differentiate among Helicobacter species. It provides an overview of biochemical and other methods to differentiate Campylobacter and Arcobacter species. Biochemical methods include DNA-DNA hybridization, protein electrophoresis and cellular fatty acid analysis. A summary of the characteristics of cultivated Helicobacter species shows that discrimination between some species may rely on only one differential feature. There are currently 11 validated enterohepatic Helicobacter species and several others that await validation or further description. The Helicobacter Bird-A isolated was later classified as H. pametensis; the other closely related organisms are not formally named and are still referred to as Helicobacter sp. Bird-B and Bird-C because they are represented by only two isolates for one species and one for the other. At present, despite its panmictic population structure, a polyphasic approach to taxonomy that is based on level of whole-genome DNA-DNA hybridization clearly identifies H. pylori as a single species.
Full text loading...
Phylogenetic tree for 18 validated Helicobacter species, 2 Candidatus species, and 9 additional provisional species, based on 16S rRNA sequence. The scale bar represents a 1% difference in nucleotide sequence as determined by measuring the length of horizontal lines connecting any two species. The tree was constructed from the differences matrix (see Table 4 ) using TREEVIEW ( 54 a).
Phylogenetic tree for 18 validated Helicobacter species, 2 Candidatus species, and 9 additional provisional species, based on 16S rRNA sequence. The scale bar represents a 1% difference in nucleotide sequence as determined by measuring the length of horizontal lines connecting any two species. The tree was constructed from the differences matrix (see Table 4 ) using TREEVIEW ( 54 a).
Characteristics of cultivated Helicobacter species a
Characteristics of cultivated Helicobacter species a
Gastric Helicobacter taxa
Gastric Helicobacter taxa
Distance matrix based on 16S rRNA comparisons
Distance matrix based on 16S rRNA comparisons
Enterohepatic Helicobacter taxa
Enterohepatic Helicobacter taxa