The Study On Feasibility Of Chirally Microbial Conversion Of D-fosfomycin To L-fosfomycin

As a kind of new antibiotic, fosfomycin has been recently recognized and then applied widely. Chemical method is mainly used in its production by now, but this chemical method has problems, such as, waste of raw materials, pollution of the environment and higher production costs. Therefore, it is imperative to develop new ways. Microbiological method has many advantages, such as high stereoselectivity, less by-products, mild reaction conditions and no pollution. Thus D-into L-fosfomycin produced by biological method has great potential.Northeast Pharmaceutical Factory is the biggest fosfomycin producer in China. We collected soil samples around the place where D-fosfomycin has been existed for a long time. The experimental steps were as follows:firstly, we filtered and enriched the mixed cells which could utilize D-fosfomycin as a sole carbon source and anti-L-fosfomycin from the soil suspensions. Secondly, the mixed cells were used to produce L-fosfomycin in two transformation mediums. Thirdly, detected by sensitive bacterial of L-fosfomation, the two fermentation broth of B and E soil samples could produced inhibition zone. And then, comparing the two fermentation broth to standard fosfomycin by the TLC, we could get the same Rf, so we could sure the L-fosfomycin can be produced in the fermentation broth.The fermentation broth which was cultured by the mixed cells of B soil sample in the transformation medium I could produce the largest inhibition zone, which diameter was2.23cm. According to the ratio between the inhibition zone diameter of L-fosfomycin and the logarithm of L-fosfomycin’s concentration, the L-fosfomation content in that fermentation broth was38.9μg/mL, and the conversion ratio was0.39%.The strains in the fermentation broth of B and E soil samples were separated and purificated. According to the different characteristics of colonies, we got more than one hundred single colony which could be devided into five categories, and eight strains were selected for16SrRNA sequencing analysis.