Project description:Purpose: Streptomyces albulus is an industrial producer of ε-poly-L-lysine, an antimicrobial cationic homo poly-amino acid used practically as a natural food preservative. Here, we present RNA sequencing data set unveiling differentially expressed transcripts during ε-poly-L-lysine production in the most extensively studied poly-L-Lys producer, S. albulus NBRC14147. Methods: During the poly-L-Lys fermentation, cells grown for 8 hours and 35 hours were harvested as growth phase cells and production phase cells, respectively, and total RNA were extracted individually. A 100-bp paired-end mRNA sequencing was performed for each sample on the Illumina HiSeq 2500 system. Result: Using an optimized data analysis workflow, we were able to map more than 44 million sequence reads per sample to the reference genome (GenBank accession number ASM385166v1). Differential gene expression analysis was performed using the edgeR. The RNA-seq data revealed that a total of 2449 genes were considered to be differentially expressed during poly-L-Lys production using a fold change cutoff of log2 less than -1 and greater than 1 (equivalent to a ±2-fold change). Conclusion: Our data will serve as a primary source for investigating the regulatory mechanism which govern poly-L-Lys production in S. albulus NBRC14147.
Project description:ε-poly-L-lysine (ε-PL) is a high value, widely used natural antimicrobial peptide additive for foods and cosmetic products that is mainly produced by S. albulus. In previous work, we developed the high-yield industrial strain S. albulus WG-608 through successive rounds of engineering. Here, we use integrated physiological, transcriptomic, and proteomics association analysis to resolve the complex mechanisms underlying high ε-PL production by comparing WG-608 with the progenitor strain M-Z18. Our results show that key genes in the glycolysis, glyoxylate, and L-lysine biosynthesis pathways are differentially upregulated in WG-608, while genes in the biosynthetic pathways for fatty acids, various branched amino acids, and secondary metabolite by-products are downregulated. This regulatory pattern results in the introduction of more carbon atoms into L-lysine biosynthesis and ε-PL production. Furthermore, transcriptional and translational upregulation of genes involved in the tricarboxylic acid cycle, oxidative phosphorylation, and pentose phosphate pathway also increase the pools of available NADH, ATP, and NADPH. In addition, significant changes in the regulation of DNA replication, transcription, and translation, two component systems, and quorum sensing may facilitate the adaptability to environmental pressure, thus further regulating the ε-PL biosynthesis. This study enables comprehensive understanding of the biosynthetic mechanisms of ε-PL in S. albulus WG-608, while providing a theoretical foundation development of advanced Streptomycetaceae microbial cell factories.
Project description:We identified genome-wide binding regions of NdgR in Streptomyces coelicolor using chromatin immunoprecipitation sequencing (ChIP-seq). We constructed 6×myc-tagged NdgR strain using homologous recombination with myc-tagging vector. Analysis of the sequencing data aligned to Streptomyces coelicolor genome database (NC_003888).
