Comparative Transcriptome Analysis of in Response to Favorable and Restrictive Nutritional Conditions.

Clavulanic acid (CA), a β-lactamase inhibitor, is industrially produced by the fermentation of . The efficiency of CA production is associated with media composition, culture conditions and physiological and genetic strain characteristics. However, the molecular pathways that govern CA regulation in remain unknown. Here we used RNA-seq to perform a comparative transcriptome analysis of ATCC 27064 wild-type strain grown in both a favorable soybean-based medium and in limited media conditions to further contribute to the understanding of metabolism and its regulation. A total of 350 genes were found to be differentially expressed between conditions; 245 genes were up-regulated in favorable conditions compared to unfavorable. The up-regulated expression of many regulatory and biosynthetic CA genes was positively associated with the favorable complex media condition along with pleiotropic regulators, including proteases and some genes whose biological function have not been previously reported. Knowledge from differences between transcriptomes from complex/defined media represents an advance in the understanding of regulatory paths involved in metabolic response, enabling the rational design of future experiments.