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Wearable robots have finally reached a point at which they can be put to more practical use. However, methods for assessing their safety have yet to be properly established. Furthermore, for ethical reasons, such assessments must be conducted without exposing the human user to unnecessary danger. Therefore, in this study, a lower-leg dummy for the safety assessment of a wearable robot was developed to evaluate the effects of a misaligned knee joint.

Nocardioides sp. strain PD653 was the first identified aerobic bacterium capable of mineralizing hexachlorobenzene (HCB). In this study, strain PD653-B2, which was unexpectedly isolated from a subculture of strain PD653, was found to lack the ability to transform HCB or pentachloronitrobenzene into pentachlorophenol. Comparative genome analysis of the two strains revealed that genetic rearrangement had occurred in strain PD653-B2, with a genomic region present in strain PD653 being deleted. In silico analysis allowed three open reading frames within this region to be identified as candidate genes involved in HCB dechlorination. Assays using recombinant Escherichia coli cells revealed that an operon is responsible for both oxidative HCB dechlorination and pentachloronitrobenzene denitration. The metabolite pentachlorophenol was detected in the cultures produced in the E. coli assays. Significantly less HCB-degrading activity occurred in assays under oxygenlimited conditions ([O 2 ] Ͻ 0.5 mg liter Ϫ1 ) than under aerobic assays, suggesting that monooxygenase is involved in the reaction. In this operon, hcbA1 was found to encode a monooxygenase involved in HCB dechlorination. This monooxygenase may form a complex with the flavin reductase encoded by hcbA3, increasing the HCBdegrading activity of PD653. IMPORTANCEThe organochlorine fungicide HCB is widely distributed in the environment. Bioremediation can effectively remove HCB from contaminated sites, but HCB-degrading microorganisms have been isolated in few studies and the genes involved in HCB degradation have not been identified. In this study, possible genes involved in the initial step of the mineralization of HCB by Nocardioides sp. strain PD653 were identified. The results improve our understanding of the protein families involved in the dechlorination of HCB to give pentachlorophenol.KEYWORDS HCB, Nocardioides sp. strain PD653, aerobic dechlorination, monooxygenase A wide range of halogenated organic compounds have been used in different applications. Hexachlorobenzene (C 6 Cl 6 ; HCB) is an organochlorine fungicide that has been used worldwide since the 1940s (1). The use of HCB was discontinued in many countries in the 1970s because of its toxicity and environmental persistence, and it was classed as a persistent organic pollutant at the Stockholm Convention in 2001. However, HCB remains a widely distributed environmental contaminant.Bioremediation is a microorganism-based approach to remediating contaminated

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