One-step of tryptophan attenuator inactivation and promoter swapping to improve the production of L-tryptophan in Escherichia coli

Gu, Pengfei; Yang, Fan; Kang, Junhua; Wang, Qian; Qi, Qingsheng

doi:10.1186/1475-2859-11-30

Cited by 69 publications

(43 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Construction of the homologous recombination fragment for swapping promoter requires five to six segments fusion [29], [37]. Multiple segments fusion is usually performed by overlap extension PCR (OE-PCR) [38], [39].…”

Section: Discussionmentioning

confidence: 99%

β-Glucan Synthase Gene Overexpression and β-Glucans Overproduction in Pleurotus ostreatus Using Promoter Swapping

et al. 2013

View full text Add to dashboard Cite

Mushroom β-glucans are potent immunological stimulators in medicine, but their productivities are very low. In this study, we successfully improved its production by promoter engineering in Pleurotus ostreatus. The promoter for β-1,3-glucan synthase gene (GLS) was replaced by the promoter of glyceraldehyde-3-phosphate dehydrogenase gene of Aspergillus nidulans. The homologous recombination fragment for swapping GLS promoter comprised five segments, which were fused by two rounds of combined touchdown PCR and overlap extension PCR (TD-OE PCR), and was introduced into P. ostreatus through PEG/CaCl2-mediated protoplast transformation. The transformants exhibited one to three fold higher transcription of GLS gene and produced 32% to 131% higher yield of β-glucans than the wild type. The polysaccharide yields had a significant positive correlation to the GLS gene expression. The infrared spectra of the polysaccharides all displayed the typical absorption peaks of β-glucans. This is the first report of successful swapping of promoters in filamentous fungi.

show abstract

Section: Discussionmentioning

confidence: 99%

β-Glucan Synthase Gene Overexpression and β-Glucans Overproduction in Pleurotus ostreatus Using Promoter Swapping

et al. 2013

View full text Add to dashboard Cite

show abstract

“…The strain also included feedback inhibition-resistant mutants of DAHP synthase and anthranilate synthase to bypass the regulation on the initial committed steps of aromatic amino acid synthesis and tryptophan synthesis branches. In addition to these modifi cations, the researchers swapped the repressible trp promoter with a relatively strong 5CP tacs promoter, in order to elevate the expression of trp operon (Gu et al 2012 ).…”

Section: Tryptophan Production In Bacterial Cellsmentioning

confidence: 99%

Tryptophan Metabolites: A Microbial Perspective

Engin

2015

Molecular and Integrative Toxicology

View full text Add to dashboard Cite

The discovery of the regulation of tryptophan biosynthetic pathway by means of a repressible operon has been recognised as a milestone in genetics. This long multistep pathway is energetically so expensive that numerous allosteric control loops exist in addition to tight genetic regulation. That's why essential amino acid tryptophan is a valuable product for food industry and animal breeding. Traditionally, vitamin auxotrophs of soil microorganisms have been used for amino acid manufacturing. However, in the age of synthetic biology, metabolic engineering has recently become the method of choice to construct the producer strains.Additionally, in contrast to mammalian cells, bacterial cells are able to produce tryptophan starting at central metabolic intermediates from pentose phosphate pathway and glycolysis. This metabolic divergence provides an excellent target for the development of novel antimicrobials which interfere with the biosynthesis of tryptophan.Tryptophan metabolism makes at least two contributions to microbial quorumsensing pathways, which may have implications in antimicrobial chemotherapy. The autoinducers of renowned Pseudomonas quinolone signalling system originate either from kynurenine or shikimate pathways. Fluorinated 4-quinolone derivative antimicrobial drugs exhibit antipathogenic effects at subinhibitory concentration, presumably by interfering with Pseudomonas quinolone signalling. Another recently recognised bacterial signal molecule is indole, a degradation product of tryptophan. Unconventional stationary phase signal molecule indole is unique, as no receptor/response regulator protein has been identifi ed to date. Instead, the effects of indole have been attributed to its physicochemical interaction with the cell membrane.

show abstract

“…Serotonin-like immunoreactivity cells resemble syntaxin-1-like immunoreactivity cells in both shape and structure and have been shown to co-localize with a subset of syntaxin-1-like immunoreactive type III cells. Synapses are only observed from type III taste cells onto ionotropic ligand-gated ion channel receptors (P2X2)like immunoreactivity nerve processes (Yang et al 2012 ).…”

Section: Taste Receptor Signalingmentioning

confidence: 99%

Tryptophan Metabolism: Implications for Biological Processes, Health and Disease

Engin¹

2015

Molecular and Integrative Toxicology

View full text Add to dashboard Cite

show abstract

One-step of tryptophan attenuator inactivation and promoter swapping to improve the production of L-tryptophan in Escherichia coli

Cited by 69 publications

References 36 publications

β-Glucan Synthase Gene Overexpression and β-Glucans Overproduction in Pleurotus ostreatus Using Promoter Swapping

β-Glucan Synthase Gene Overexpression and β-Glucans Overproduction in Pleurotus ostreatus Using Promoter Swapping

Tryptophan Metabolites: A Microbial Perspective

Tryptophan Metabolism: Implications for Biological Processes, Health and Disease

Contact Info

Product

Resources

About