Chapter 6 Regulation of Antibiotic Production by Bacterial Hormones

Antibiotic production is regulated by numerous signals, including the so-called bacterial hormones found in antibiotic producing organisms such as Streptomyces. These signals, the γ-butyrolactones, are produced in very small quantities, which has hindered their structural elucidation and made it difficult to assess whether they are being produced. In this chapter, we describe a rapid small-scale extraction method from either solid or liquid cultures in scales of one plate or 50 ml of medium. Also described is a bioassay to detect the γ-butyrolactones by determining either the production of pigmented antibiotic of Streptomyces coelicolor or kanamycin resistant growth on addition of the γ-butyrolactones. We also describe some insights into the identification of the γ-butyrolactone receptor and its targets and also the gel retardation conditions with three differently labeled probes. © 2009 Elsevier Inc. All rights reserved.