PMID: 42347Aug 1, 1979

Hyperproduction of tryptophan by Escherichia coli: genetic manipulation of the pathways leading to tryptophan formation

Applied and Environmental Microbiology
D E Tribe, J Pittard

Abstract

Conversion of glucose and ammonium salts into tryptophan by mutants of Escherichia coli was examined as part of a feasibility study on the manufacture of tryptophan. This involved construction, largely by transduction, or a variety of multiple-mutation strains with defined genotypes. By comparing the properties of these strains, we were able to define in biochemical terms several changes that significantly enhance process productivity, namely (i) release of the first enzyme of the common pathway of aromatic biosynthesis and the first enzyme of the tryptophan pathway (3-deoxy-D-arabino-heptulosonate 7-phosphate synthase and the anthranilate aggregate, respectively) from inhibition by end products, (ii) blockage of the diversion of chorismate to phenylalanine and tyrosine biosynthesis, and (iii) presence of highly elevated tryptophan pathway enzyme levels, such as result from interference with both repression and attenuation, combined with gene amplification. By using strains carrying appropriate mutations to effect all of these changes, high values of specific productivity were obtained in bath culture (approximately 80 mg/g [dry weight] per h). Furthermore, a pronounced decay in the level of 3-deoxy-D-arabino-heptulosonate 7-ph...Continue Reading

References

Dec 24, 2005·Applied Microbiology and Biotechnology·Masato Ikeda
Feb 5, 1988·Biotechnology and Bioengineering·S Sinha
Jan 1, 1987·Critical Reviews in Biotechnology·J L MilnerJ M Wood
May 23, 2013·Applied Microbiology and Biotechnology·Pengfei GuQingsheng Qi
Sep 11, 2018·Biotechnology and Bioengineering·Julia TröndleDirk Weuster-Botz
Nov 15, 2018·Journal of Industrial Microbiology & Biotechnology·Hao NiuPengfei Gu

Related Concepts

Tryptophan Synthase
Biochemical Pathway
Chorismic Acid
Tryptophan
Ammonium salts
Alkalescens-Dispar Group
Gene Amplification
Clinical Enzyme Tests (Procedure)
2-Dehydro-3-Deoxyphosphoheptonate Aldolase
Genetic Manipulation

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Synapse Loss as Therapeutic Target in MS

As we age, the number of synapses present in the human brain starts to decline, but in neurodegenerative diseases this occurs at an accelerated rate. In MS, it has been shown that there is a reduction in synaptic density, which presents a potential target for treatment. Here is the latest research on synapse loss as a therapeutic target in MS.

Artificial Intelligence in Cardiac Imaging

Artificial intelligence (ai) techniques are increasingly applied to cardiovascular (cv) medicine in cardiac imaging analysis. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

Social Learning

Social learning involves learning new behaviors through observation, imitation and modeling. Follow this feed to stay up to date on the latest research.

Cell Atlas of the Human Eye

Constructing a cell atlas of the human eye will require transcriptomic and histologic analysis over the lifespan. This understanding will aid in the study of development and disease. Find the latest research pertaining to the Cell Atlas of the Human Eye here.

Single Cell Chromatin Profiling

Techniques like ATAC-seq and CUT&Tag have the potential to allow single cell profiling of chromatin accessibility, histones, and TFs. This will provide novel insight into cellular heterogeneity and cell states. Discover the latest research on single cell chromatin profiling here.

Genetic Screens in iPSC-derived Brain Cells

Genetic screening is a critical tool that can be employed to define and understand gene function and interaction. This feed focuses on genetic screens conducted using induced pluripotent stem cell (iPSC)-derived brain cells.