Wolbachia genes

Exhaustive surveys have not been carried out to determine the prevalence of infection within a single species of filarial nematode. However, infection was found in all eight specimens of D. immitis collected from worldwide locations, indicating that infection prevalence is likely to be close to 100% (Sironi et al., 1995). Sequences of Wolbachia ftsZ genes from... 

Table 2.1. Filarial nematodes infected with intracellular bacteria. The method of detection is shown. Neither electron microscopy nor the immuno-histochemical staining techniques used are to be regarded as Wolbachia specific (see note). Positive identification of intracellular bacteria as Wolbachia is shown only where PCR amplified products of rRNA or ftsZ genes have been sequenced. ...

The effectors of the mammalian host immune attack against filaria include reactive oxygen intermediates. Filarial nematodes express glutathione peroxidase, thioredoxin peroxidase and superoxide dismutase at their surface - enzymes believed to protect the nematode from this attack (Selkirk et al., 1998). A bacterial catalase gene has been identified that most probably derives from the endosymbiont genome (Henkle-Duhrsen et al., 1998) this enzyme may contribute with other enzymes to the protection of both Wolbachia and its nematode host from oxygen radicals. 

Bazzocchi, C., Jamnongluk, W., O Neill, S.L., Anderson, T.J.C., Genchi, C. and Bandi C. (2000a) u />gene sequences from the Wolbachia of filarial nematodes. 

Zhou, W., Rousset, F. and O Neill, S. (1998) Phylogeny and PCR-based classification of Wolbachia strains using wsp gene sequences. Proceedings of the Royal Society of London B 265, 509-515. 

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