Project description:FROG and miniFROG reports are given for the genome-scale metabolic network of Bacillus licheniformis WX-02. The model iWX1009 contains 1009 genes, 1141 metabolites and 1762 reactions and is the study of poly-γ-glutamic acid (γ-PGA) synthesis. The model can be found in the Supplementary data of the Guo et al, 2016 paper cited here.
2024-10-15 | MODEL2408030002 | BioModels
Project description:Effects of poly-gamma-glutamic acid application on soil bacterial community composition
Project description:The gene expression levels in murine bone marrow-derived dendritic cells treated with γ-PGA NPs were examined by oligonucleitide microarray and compared with those in the cells treated with other adjuvants. The gene expression of proinflammatory chemokines, cytokines, and costimulatory molecules was upregulated considerably in DCs treated with γ-PGA NPs. The upregulation pattern was similar to that in DCs treated with LPS but not in DCs treated with unparticulate γ-PGA. The activation of DCs by γ-PGA NPs was confirmed by real-time RT-PCR analysis for the genes related to TLR signaling. The effect of γ-PGA NPs on DCs was not annihilated by treating with polymixin B, an inhibitor of LPS. Furthermore, the immunization of mice with γ-PGA NPs carrying OVA significantly induced Ag-specific CD8+ T cells and Ag-specific production of IL-2, TNF-α, and IFN-γ from the cells. Such activities of γ-PGA NPs were more prominent, when compared to the immunization with OVA plus aluminum hydroxide or OVA plus CFA. These results suggest that γ-PGA NPs induce a CD8+ T cell response through activating innate immunity in a fashion different from that of LPS. Thus, γ-PGA NPs may be an attractive adjuvant to be further developed for vaccine therapy.
Project description:Biofilms are structured communities of tightly associated cells that constitute the predominant state of bacterial growth in natural and human-made environments. Although the core genetic circuitry that controls biofilm formation in model bacteria such as Bacillus subtilis has been well characterized, little is known about the role that metabolism plays in this complex developmental process. Here, we performed a time-resolved analysis of the metabolic changes associated with pellicle biofilm formation and development in B. subtilis by combining metabolomic, transcriptomic, and proteomic analyses. We report a surprisingly widespread and dynamic remodeling of metabolism affecting central carbon metabolism, primary biosynthetic pathways, fermentation pathways, and secondary metabolism. Most of these metabolic alterations were hitherto unrecognized as biofilm-associated. For example, we observed increased activity of the tricarboxylic acid (TCA) cycle during early biofilm growth, a shift from fatty acid biosynthesis to fatty acid degradation, reorganization of iron metabolism and transport, and a switch from acetate to acetoin fermentation. Close agreement between metabolomic, transcriptomic, and proteomic measurements indicated that remodeling of metabolism during biofilm development was largely controlled at the transcriptional level. Our results also provide insights into the transcription factors and regulatory networks involved in this complex metabolic remodeling. Following these results, we demonstrate that acetoin production via acetolactate synthase is essential for robust biofilm growth and has the dual role of conserving redox balance and maintaining extracellular pH. This study represents a comprehensive systems-level investigation of the metabolic remodeling occurring during B. subtilis biofilm development that will serve as a useful roadmap for future studies on biofilm physiology.
2019-03-27 | GSE128875 | GEO
Project description:Rhizosphere soil bacterial community in chromium-contaminated or copper-contaminated soil with poly-gamma-glutamic acid application
Project description:Purpose: High γ-aminobutyric acid (GABA)-producing Levilactobacillus brevis strain NPS-QW 145 along with Streptococcus thermophilus (one of the two starter bacteria used to make yogurt for its proteolytic activity) to enhance GABA production in milk. But a mechanistic understanding on how Levilactobacillus brevis cooperated with S. thermophilus to stimulate GABA production has been lacking. Method: Metatranscriptomic analyses combined with peptidomics were carried out to unravel the casein and lactose utilization patterns during milk fermentation with the co-culture. Results: We found particular peptides hydrolyzed by S. thermophilus 1275 were transported and biodegraded with peptidase in Lb. brevis 145 to meet the growth needs of the latter. In addition, amino acid synthesis and metabolism in Lb. brevis 145 were also activated to further support its growth. Glucose, as a result of lactose hydrolysis by S. thermophilus 1275, but not available lactose in milk, was outcompeted by Lb. brevis 145 as a main carbon source for glycolysis to produce ATP.In the stationary phase, under the acidic condition due to accumulation of lactic acid produced by S. thermophilus 1275, genes expression involved in pyridoxal phosphate (coenzyme of glutamic acid decarboxylase) metabolism and glutamic acid decarboxylase (Gad) in Lb. brevis 145 were induced for GABA production.