The Streptomyces coelicolor Small ORF trpM Stimulates Growth and Morphological Development and Exerts Opposite Effects on Actinorhodin and Calcium-Dependent Antibiotic Production

Abstract

Frontiers in Microbiology | www.frontiersin.org February 2020 | Volume 11 | Article 224 Vassallo et al.trpM Stimulates Actinorhodin Production down-representation of proteins involved in central carbon and amino acid metabolism. At the metabolic level, this corresponded to a differential accumulation pattern of different amino acids -including aromatic ones but tryptophan -and central carbon intermediates. PepA was also down-represented in Sco-trpMKI. The latter was produced as recombinant His-tagged protein and was originally proven having the predicted aminopeptidase activity. Altogether, these results highlight the stimulatory effect of trpM in S. coelicolor growth and ACT biosynthesis, which are elicited through the modulation of various metabolic pathways and PepA representation, further confirming the complexity of regulatory networks that control antibiotic production in actinomycetes.

Small Open Reading Frames: How Important Are They for Molecular Evolution?

“…This hypothesis is based on the fact that hundreds of smORFs are described as highly conserved but display low expression, low translation efficiency and are observed in transcripts with non-coding characteristics (Cabili et al, 2011;Aspden et al, 2014;Bazzini et al, 2014). However, the nearly neutral theory (Ohta, 2002) suggests that non-coding parts of fixed smORF transcripts are modified by random genetic drift, in some cases, producing small advantageous (or disadvantageous) adaptive effects throughout evolution; thus, we propose that, at a certain point, these modifications refine and elevate the coding potential of smORF transcripts and consequently enhance the adaptive relevance of their peptides, as seen in a large number of important smORF peptides recently discovered (e.g., Magny et al, 2013;Anderson et al, 2015;Lauressergues et al, 2015;Nelson et al, 2016;Pengpeng et al, 2017;Kim et al, 2018;Polycarpou-Schwarz et al, 2018;Chugunova et al, 2019;Tobias-Santos et al, 2019;Pang et al, 2020;Vassallo et al, 2020). Importantly, the acquisition of several optimal coding features might be favored after the smORF has been selected for, because modifications driven by genetic drift could be fixed by natural selection if they improve the translation efficiency of the newly selected smORF.…”

Unravelling the DNA sequences carried by Streptomyces coelicolor membrane vesicles

“…The collected biomass was washed twice with sterile water and resuspended in 30 mL of sterile water. Then, 10 mL of the bacterial suspension were inoculated in 500 mL of minimal medium [NaNO 3 (1 g/L), MgSO 4 ·7H 2 O (0.5 g/L), KCl (0.5 g/L), KH 2 PO 4 (1 g/L), glucose (10 g/L), trace element solution (1 mL/L), pH 7; trace element solution contained FeSO 4 ·7H 2 O (1 g/100 mL), ZnCl 2 (1 g/100 mL), and biotin (0.1 g/100 mL)] (MM) 51 , in a 2 L-baffled flask, and incubated at 30 °C for 136 h, under shaking at 180 rpm. S. coelicolor membrane vesicles were isolated and purified as described previously 4 .…”

Streptomyces coelicolor Vesicles: Many Molecules To Be Delivered

“… Streptomyces coelicolor is a model of study widely used to investigate the regulation of microbial morphological differentiation and the production of bioactive molecules ( 13 ). S. coelicolor is characterized by a complex life cycle, encompassing its transition from a vegetative mycelium to reproductive aerial hyphae that eventually differentiate in chains of spores.…”