A Bacillus subtilis cell factory for producing scyllo-inositol, a disease-modifying therapeutic agent for Alzheimer's disease

摘要

We previously demonstrated a prototype of a cell factory, which enables conversion from myo-inositol (MI) to scyllo-inositol (SI), using a strain of Bacillus subtilis with the modified inositol metabolic pathway. However, it wasted half of the MI, and the conversion rate was limited to only 40-50%. In this study all 'useless' genes involved in MI and SI metabolism were deleted, and MI was not wasted in the new strain though no elevation in SI production was achieved. IolG and IolW are the key enzymes responsible for the conversion. Overexpression of IolG and IolW was attempted for the further elevation in the conversion rate, the rate reached to 100% (10 g/l/48 h) when IolG and IolW were simultaneously overexpressed. The improved conversion was achieved only in the presence of enriched nutrition in the form of 2% (w/v) Bacto soytone in the medium, which may be due to the increasing demand for regeneration of cofactors.