Dataset Information

Development of Bacillus subtilis mutants to produce tryptophan in pigs.

ABSTRACT:

Objectives

To generate tryptophan-overproducing Bacillus subtilis strains for in situ use in pigs, to reduce the feed cost for farmers and nitrogen pollution.

Results

A novel concept has been investigated-to generate B. subtilis strains able to produce tryptophan (Trp) in situ in pigs. Mutagenesis by UV was combined with selection on Trp and purine analogues in an iterative process. Two mutants from different wild types were obtained, mutant 1 (M1) produced 1 mg Trp/l and mutant 2 (M2) 14 mg Trp/l. Genome sequence analysis revealed that M1 had three single nuclear polymorphisms (SNPs) and M2 had two SNPs compared to the wild type strains. In both mutants SNPs were found in genes regulating tryptophan synthesis. Reverse transcription PCR confirmed up-regulation of the tryptophan synthesis genes in both mutants, the expression was up to 3 times higher in M2 than in M1.

Conclusions

Tryptophan-excreting B. subtilis strains were obtained with UV-mutagenesis and analogue selection and can be used in animal feed applications.

SUBMITTER: Bjerre K

PROVIDER: S-EPMC5247549 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Development of Bacillus subtilis mutants to produce tryptophan in pigs.

Bjerre Karin K Cantor Mette D MD Nørgaard Jan V JV Poulsen Hanne D HD Blaabjerg Karoline K Canibe Nuria N Jensen Bent B BB Stuer-Lauridsen Birgitte B Nielsen Bea B Derkx Patrick M F PM

Biotechnology letters 20161103 2

<h4>Objectives</h4>To generate tryptophan-overproducing Bacillus subtilis strains for in situ use in pigs, to reduce the feed cost for farmers and nitrogen pollution.<h4>Results</h4>A novel concept has been investigated-to generate B. subtilis strains able to produce tryptophan (Trp) in situ in pigs. Mutagenesis by UV was combined with selection on Trp and purine analogues in an iterative process. Two mutants from different wild types were obtained, mutant 1 (M1) produced 1 mg Trp/l and mutant 2 ...[more]

PMID: 27812824

Similar Datasets

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 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 upon these results, we demonstrated 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 report represents a comprehensive systems-level investigation of the metabolic remodeling occurring during B. subtilis biofilm development that will serve as a useful road map for future studies on biofilm physiology.IMPORTANCE Bacterial biofilms are ubiquitous in natural environments and play an important role in many clinical, industrial, and ecological settings. Although much is known about the transcriptional regulatory networks that control biofilm formation in model bacteria such as Bacillus subtilis, very little is known about the role of metabolism in this complex developmental process. To address this important knowledge gap, we performed a time-resolved analysis of the metabolic changes associated with bacterial biofilm development in B. subtilis by combining metabolomic, transcriptomic, and proteomic analyses. Here, we report a widespread and dynamic remodeling of metabolism affecting central carbon metabolism, primary biosynthetic pathways, fermentation pathways, and secondary metabolism. This report serves as a unique hypothesis-generating resource for future studies on bacterial biofilm physiology. Outside the biofilm research area, this work should also prove relevant to any investigators interested in microbial physiology and metabolism.

Dataset Information

Development of Bacillus subtilis mutants to produce tryptophan in pigs.

Objectives

Results

Conclusions

Publications

Development of Bacillus subtilis mutants to produce tryptophan in pigs.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets