Journal of Bioengineering & Biomedical Science

Diauxic and Antimicrobial Growth Phases of Streptomyces Tenjimariensis: Metabolite Profiling and Gene Expression

Abstract

Judith R. Denery , Michael J. Cooney and Qing X. Li1

This work reports the use of metabolic profiling and PCR techniques as a means of studying the growth of Streptomyces tenjimariensis . Metabolic profiles were created from gas chromatography–mass spectrometry analysis of extracts prepared through extraction of the intracellular contents followed by fractionation of the polar metabolites and trimethylsilyl derivatization. All chromatograms yielded profiles of between 100 and 200 metabolites.The major metabolite groups including organic acids, amino acids, sugars, sugar alcohols, and phosphatidyl sugar alcohols were identified and their profiles correlated to growth stage and antimicrobial activity. Statistical analysis including analysis of variance, hierarchical cluster analysis, and principal component analysis suggested that differences between the major growth phases could be distinguished, and may be used to establish patterns amongst key metabolites. The expression of four enzyme genes involving substrate utilization and istamycin biosynthesis was detected with reverse transcriptase-PCR across four time points during the growth of S. tenjimariensis .