Mutant Confirmation Of Saccharopolyspora ERYTHRAEA RS-19-IBHXR And Its Valine-Content Analysis Using Pyrolysis Mass Spectrometry

Abstract: Mutant Sacdiaropolyspora erythraea RS-19, a higher erythromycin titer mutant, has been proved to be resistant to some valine analogs (valine hydroxamate [VHx], ^-amino-butyric acid hydroxamate [iBHx], and n-butyric hydroxamate [n-BHx]). The ^-amino-butyric hydroxamate-resistant of the mutant (Sac. erythraea RS-19-iBHxr) showed a stable erythromycin production over ten generations compared to those of Sac. erythraea RS-19 and Sac. erythraea RS-19-VHxr. A Pyrolysis Mass-Spectrometric (PyMS) analysis was carried out to confirm whether the Sac. erythraea RS-19-/BHxr is a true mutant, and whether its increasing erythromycin production is caused by the increasing valine (a prae-precursor of erythromycin biosynthesis) production in the mutant. The PCCV1-PCCV2 ordination diagram resulted by the parent (the wild type of Sac. erythraea) and the mutant showed that the mutant was significantly discriminated from the parent, either in the exponential and/or stationary phase. The PyMS spectra of Sac. erythraea RS-19-fBHxr, the parent (wild type) Sac. erythraea, and their difference, showed that the valine content of the mutant cells was much higher than that of the parent. Therefore there is a strong possibility that the increasing valine content in the mutant cells increases its erythromycin production. Keywords:Saccharopolyspora erythraea RS-19-iBH/- PyMS -PC-CV Analysi