Submitted to: Mycological Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/16/1998
Publication Date: N/A
Citation: JONES, K.G., DOWD, P.F., BLACKWELL, M. POLYPHYLETIC ORIGINS OF YEAST-LIKE ENDOCYTOBIONTS FROM ANOBIID AND CERAMBYCID BEETLES. MYCOLOGICAL RESEARCH. 1999. v. 103(5). p. 542-546. Interpretive Summary: Insects cause billions of dollars in damages each year. Many insects have microorganisms that live inside of them and are necessary for their survival. Potentially, insect populations may be controlled via antibiotic control of their essential gut microflora, a method much less toxic than traditional insecticide use. However, the type of microorganism in the insect is often uncertain due to the degree of adaptation that has occurred. It is important to know what type of miroorganism is present in order to select a potential antibiotic for its control. Molecular biological techniques were used to identify the type of microorganism present in several species of insect beetles that are major pests of trees or stored products. It is now possible to better select antibiotics potentially useful in controlling some major pest insect species through killing their essential microorganisms. It is possible that antibiotics useful for controlling the insect microorganisms are the same ones presently being used to control plant pathogens which are pests of the same plants hosting the insect pests. Such a scenario would save application costs for growers. This technology may also reduce pesticide applications overall with associated health and environmental benefits to all citizens.
Technical Abstract: Cladistic analysis of nucleotide characters derived from partial 18S rDNA sequences has been used to infer phylogenetic relationships among five Candida species that exist in nature strictly as intracellular gut endocytobionts of anobiid or cerambycid beetles. Concordant with their assumed taxonomic status, all five species resolve within Saccharomycetales. For both the anobiid-derived taxa, C. ernobii, C. karawaeiwii and C. xestobii, and the cerambycid-derived taxa, C. tenuis and C. rhagii, this phylogenetic position clearly discriminates Candida yeasts from the anobiid yeast-like endocytobionts in Symbiotaphrina which resolve within filamentous ascomycetes. The analyses provide no evidence for a discrete lineage of Candida endocytobionts within Saccharomycetales. Rather, each of the anobiid symbionts and the cerambycid-derived species resolve in separate clades. These data confirm the polyphyletic origins of intracellular symbioses between ascomycetes and Coleoptera and provide another example of convergent evolution in fungal- arthropod associations. The implications of the phylogenetic data for theories on the origins of endocytobiosis are discussed.