TY - JOUR
T1 - Phylogenetic relationships of necrogenic Erwinia and Brenneria species as revealed by glyceraldehyde-3-phosphate dehydrogenase gene sequences
AU - Brown, E. W.
AU - Davis, R. M.
AU - Gouk, C.
AU - Van der Zwet, T.
PY - 2000
Y1 - 2000
N2 - Recent examination of the relationships of the dry necrosis-inducing (necrogenic) erwinias using 16S rDNA sequences demonstrated that these bacteria comprise a polyphyletic group and, therefore, have been subdivided into three distinct genera, Erwinia, Brenneria and Pectobacterium, with the classical 'amylovora' group species now being distributed nearly evenly among the first two. To further assess the molecular evolutionary relationships between current necrogenic Erwinia and Brenneria species, as well as between these genera and the exclusively soft-rotting genus Pectobacterium, the glyceraldehyde-3-phosphate dehydrogenase (gapDH) genes from 57 Erwinia and Brenneria isolates along with Pectobacterium type strains were PCR-amplified, sequenced and subjected to phylogenetic analysis. Pairwise alignments of cloned gapDH genes revealed remarkably high interspecies genetic diversity among necrogenic isolates. Four evolutionary clades of necrogenic species were described that assorted more closely to known soft-rotting species than to each other. Interclade comparisons of gapDH nucleotide sequences revealed as much genetic divergence between these four necrogenic clades as existed between necrogenic and soft-rotting clades. An examination of the phylogenetic utility of the gapDH gene in light of current 16S rDNA clustering of these species revealed varying levels of taxonomic congruence between these genes for the structure of Erwinia, Brenneria and Pectobacterium. These analyses suggest that, while gapDH possesses sufficient genetic variation to fully differentiate Erwinia and Brenneria species, the gene may not accurately reflect interspecies taxonomic relatedness among all three phytopathogenic genera.
AB - Recent examination of the relationships of the dry necrosis-inducing (necrogenic) erwinias using 16S rDNA sequences demonstrated that these bacteria comprise a polyphyletic group and, therefore, have been subdivided into three distinct genera, Erwinia, Brenneria and Pectobacterium, with the classical 'amylovora' group species now being distributed nearly evenly among the first two. To further assess the molecular evolutionary relationships between current necrogenic Erwinia and Brenneria species, as well as between these genera and the exclusively soft-rotting genus Pectobacterium, the glyceraldehyde-3-phosphate dehydrogenase (gapDH) genes from 57 Erwinia and Brenneria isolates along with Pectobacterium type strains were PCR-amplified, sequenced and subjected to phylogenetic analysis. Pairwise alignments of cloned gapDH genes revealed remarkably high interspecies genetic diversity among necrogenic isolates. Four evolutionary clades of necrogenic species were described that assorted more closely to known soft-rotting species than to each other. Interclade comparisons of gapDH nucleotide sequences revealed as much genetic divergence between these four necrogenic clades as existed between necrogenic and soft-rotting clades. An examination of the phylogenetic utility of the gapDH gene in light of current 16S rDNA clustering of these species revealed varying levels of taxonomic congruence between these genes for the structure of Erwinia, Brenneria and Pectobacterium. These analyses suggest that, while gapDH possesses sufficient genetic variation to fully differentiate Erwinia and Brenneria species, the gene may not accurately reflect interspecies taxonomic relatedness among all three phytopathogenic genera.
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U2 - 10.1099/00207713-50-6-2057
DO - 10.1099/00207713-50-6-2057
M3 - Article
C2 - 11155980
AN - SCOPUS:0034521790
SN - 1466-5026
VL - 50
SP - 2057
EP - 2068
JO - International journal of systematic and evolutionary microbiology
JF - International journal of systematic and evolutionary microbiology
IS - 6
ER -