title: Evolutionary relationships of primary prokaryotic endosymbionts of whiteflies and their hosts.
abstract: Whiteflies (Hemiptera: Sternorrhyncha: Aleyrodidae) are plant sap-sucking insects that harbor prokaryotic primary endosymbionts (P-endosymbionts) within specialized cells located in their body cavity. Four-kilobase DNA fragments containing 16S-23S ribosomal DNA (rDNA) were amplified from the P-endosymbiont of 24 whiteflies from 22 different species of 2 whitefly subfamilies. In addition, 3-kb DNA fragments containing mitochondrial cytB, nd1, and large-subunit rDNA (LrDNA) were amplified from 17 whitefly species. Comparisons of the P-endosymbiont (16S-23S rDNA) and host (cytB-nd1-LrDNA) phylogenetic trees indicated overall congruence consistent with a single infection of a whitefly ancestor with a bacterium and subsequent cospeciation (cocladogenesis) of the host and the P-endosymbiont. On the basis of both the P-endosymbiont and host trees, the whiteflies could be subdivided into at least five clusters. The major subdivision was between the subfamilies Aleyrodinae and Aleurodicinae. Unlike the P-endosymbionts of may other insects, the P-endosymbionts of whiteflies were related to Pseudomonas and possibly to the P-endosymbionts of psyllids. The lineage consisting of the P-endosymbionts of whiteflies is given the designation "Candidatus Portiera" gen. nov., with a single species, "Candidatus Portiera aleyrodidarum" sp. nov.
authors.affiliation: Microbiology Section, University of California, Davis, 95616-8665, USA.
authors.forename: MyLo Ly
authors.initials: ML
authors.lastname: Thao
authors.forename: Paul
authors.initials: P
authors.lastname: Baumann
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D004269:DNA, Bacterial / Q000032:analysis; D004272:DNA, Mitochondrial / Q000235:genetics; D004275:DNA, Ribosomal / Q000032:analysis; D019143:Evolution, Molecular; D006430:Hemiptera / Q000145:classification / Q000235:genetics / Q000382:microbiology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013559:Symbiosis
chemical_list: D004269:DNA, Bacterial; D004272:DNA, Mitochondrial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012338:RNA, Ribosomal, 23S