6S-Like scr3559 RNA Affects Development and Antibiotic Production in Streptomyces coelicolor.

Jan Bobek,Matouš Čihák,Dita Šetinová,Marie Elliot,Adéla Mikulová

doi:10.3390/microorganisms9102004

Abstract

Regulatory RNAs control a number of physiological processes in bacterial cells. Here we report on a 6S-like RNA transcript (scr3559) that affects both development and antibiotic production in Streptomyces coelicolor. Its expression is enhanced during the transition to stationary phase. Strains that over-expressed the scr3559 gene region exhibited a shortened exponential growth phase in comparison with a control strain; accelerated aerial mycelium formation and spore maturation; alongside an elevated production of actinorhodin and undecylprodigiosin. These observations were supported by LC-MS analyses of other produced metabolites, including: germicidins, desferrioxamines, and coelimycin. A subsequent microarray differential analysis revealed increased expression of genes associated with the described morphological and physiological changes. Structural and functional similarities between the scr3559 transcript and 6S RNA, and its possible employment in regulating secondary metabolite production are discussed.

Highlights

It is noteworthy that it is oriented downstream of SCO3559, as illustrated here in Figure 1 and is in accordance with the RNA sequence shown in both the above-mentioned publications, the gene is mistakenly depicted in the opposite direction in Mikulík et al [16], where it is dubbed ssrS
Scr3559 RNA levels increase during the transition into stationary phase, and culminate with onset of antibiotic production
The phenotypic observations presented here imply that scr3559 RNA plays a central role in the developmental control mechanisms of Streptomyces bacteria

Summary

Introduction

The soil niche represents a harsh living environment where the natural microbial inhabitants have evolved various nutrient-acquiring and life-defending strategies. Streptomyces have a complex developmental life cycle that begins with germinating spores. They form branching vegetative hyphae that differentiate into aerial mycelium and spores again [1,2,3,4]. The streptomycetes possess extraordinary genetic equipment for sensing extracellular signals and producing various specialized metabolites [5]. Among other applications, these molecules encompass over two-thirds of the clinically useful antibiotics and other compounds of industrial value [6]. The developmental complexity and antibiotic biosynthesis of these organisms require a complex regulatory network, which is responsible for addressing proper responses to changes in environmental conditions [7]

Methods

Results

Discussion

Conclusion