Project description:Corynebacterium glutamicum strain ATCC 21831 is a producer of L-arginine that was created by random mutagenesis. It is resistant to the arginine structural analogue canavanine. In order to identify potential bottlenecks in the biosynthetic pathway that leads to this industrially important amino acid, relative metabolite abundances of biosynthetic intermediates were determined in comparison to the type strain ATCC 13032. An extract of U13C-labeled biomass was used as internal standard, to correct for different ionization efficiencies. Metabolites were identified using the ALLocator web platform.
Project description:Welan gum is mainly produced by Sphingomonas sp. ATCC 31555 and has broad applications in industry such as that in cement production. Both carbon and nitrogen sources are essential for welan production. However, how nitrogen sources affect the metabolism and gene transcription of welan remains elusive. Here, we used next-generation sequencing RNA-seq to analyze the transcriptome of Sphingomonas sp. ATCC 31555 in the presence of inorganic or organic nitrogen sources. Enriched gene expression and pathway analysis suggest that organic nitrogen sources significantly enhanced the expression of genes in central metabolic pathways of Sphingomonas sp. ATCC 31555 and those critical for welan synthesis compared to that observed using inorganic nitrogen sources. The present study improves our understanding of the molecular mechanism underlying the use of nitrogen in welan synthesis in Sphingomonas sp., as well as provides an important transcriptome resource for Sphingomonas sp. in relation to nitrogen sources.
Project description:Welan gum is mainly produced by Sphingomonas sp. ATCC 31555 and has broad applications in industry such as that in cement production. Both carbon and nitrogen sources are essential for welan production. However, how nitrogen sources affect the metabolism and gene transcription of welan remains elusive. Here, we used next-generation sequencing RNA-seq to analyze the transcriptome of Sphingomonas sp. ATCC 31555 in the presence of inorganic or organic nitrogen sources. Enriched gene expression and pathway analysis suggest that organic nitrogen sources significantly enhanced the expression of genes in central metabolic pathways of Sphingomonas sp. ATCC 31555 and those critical for welan synthesis compared to that observed using inorganic nitrogen sources. The present study improves our understanding of the molecular mechanism underlying the use of nitrogen in welan synthesis in Sphingomonas sp., as well as provides an important transcriptome resource for Sphingomonas sp. in relation to nitrogen sources. Sphingomonas sp. ATCC 31555 strain (stored in our laboratory) was first seeded in an inoculum medium (20 g/L glucose, 3 g/L yeast extract, 3 g/L malt extract, and 5 g/L fish meal protein peptone, pH 7.0), and then cultured in a fermentation medium containing 40 g/L sucrose, 4.0 g/L nitrogen source, 0.6 g/L KH2PO4, and 0.2 g/L MgSO4.7H2O at 37°C. The nitrogen sources used in the present study were as follows: NaNO3 (4.0 g/L) as inorganic nitrogen (IN), beef extract (4.0 g/L) as organic nitrogen (ON), and NaNO3 (1.5 g/L) + beef extract (2.5 g/L) as complex nitrogen (CN). All cultivations were conducted in flasks with constant rotary shaking at 400â??1,000 rpm and 37°C.
Project description:Purpose:first,we want to find the genes revelant to curdlan synthesis and oxygen regulation, second, we want to research the function of fnrN gene in Agrobacterium sp. ATCC 31749. Method: samples of cell growth phase, curdlan-producing phase (normoxia) and curdlan-producing phase (micro-oxygen treated) in both Agrobacterium sp. ATCC 31749 wild strain and ΔfnrN strain were collectecd to extract mRNA. Each sample was treated in duplicate. The softwares we used include fastqc, trimmomatic, TopHat2 and Cufflinks. Illumina Hiseq4000 was used to complete the research.
