“Candidatus Liberobacter asiaticum” and “Candidatus Liberobacter africanum,” the Two Species Associated with Citrus Huanglongbing (Greening) Disease
نویسندگان
چکیده
16S/23S intergenic spacer regions from the rRNA operons of two strains of “Candidatus Liberobacter asiaticum” and one strain of “Candidatus Liberobacter africanum” were cloned and sequenced. The intergenic spacers of the two “Candidatus L. asiaticum” strains studied are identical and contain the genes for isoleucine tRNA (tRNA”‘) and alanine tRNA (tRNAMa) separated by 11 nucleotides. The intergenic spacer of the “Candidatus L. africanum” strain contains only one tRNA gene (tRNANa). The level of homology between the intergenic spacers of the two liberobacter species is 79.46%. Ribosomal operons with 16S/23S spacer regions other than those studied might be present in the two “Candidatus Liberobacter” species.
منابع مشابه
PCR detection of the two 'Candidatus' Liberobacter species associated with greening disease of citrus.
Greening is a severe and widespread disease of citrus in two main citrus growing areas of the world, Asia and Africa. It is caused by an uncultured phloem restricted bacterium that we have recently characterized from the sequence of its 16S ribosomal DNA. The bacterium is a new "Candidatus' genus, Liberobacter, in the alpha subdivision of the proteobacteria, and two 'Candidatus species' have be...
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