Isolation of transposon Tn5 mutant affected in the metabolism of 18 beta-glycyrrhetinic acid

Transposon Tn5 mutagenesis was carried out to clarify the metabolism of 18 beta -glycyrrhetinic acid (18 beta -GRA) in Sphingomonas paucimobilis G5. A Tn5-induced mutant strain, named TM9638 that was affected in its metabolis m of 18 beta -GRA, was isolated. This mutant accumulated three metabolites, designated as M-A, M-B and M-C, from 18 beta -GRA in the culture broth. M- A was accumulated in the culture broth of wild type strain, but M-B and M-C were not accumulated in the culture broth of wild type strain. M-B and M-C were isolated from the culture broth of TM9638 and the chemical structures were elucidated by NMR and GC-MS.