scholarly journals Improved Squalene Production via Modulation of the Methylerythritol 4-Phosphate Pathway and Heterologous Expression of Genes from Streptomyces peucetius ATCC 27952 in Escherichia coli

2009 ◽  
Vol 75 (22) ◽  
pp. 7291-7293 ◽  
Author(s):  
Gopal Prasad Ghimire ◽  
Hei Chan Lee ◽  
Jae Kyung Sohng

ABSTRACT Putative hopanoid genes from Streptomyces peucetius were introduced into Escherichia coli to improve the production of squalene, an industrially important compound. High expression of hopA and hopB (encoding squalene/phytoene synthases) together with hopD (encoding farnesyl diphosphate synthase) yielded 4.1 mg/liter of squalene. This level was elevated to 11.8 mg/liter when there was also increased expression of dxs and idi, E. coli genes encoding 1-deoxy-d-xylulose 5-phosphate synthase and isopentenyl diphosphate isomerase.

1999 ◽  
Vol 181 (15) ◽  
pp. 4499-4504 ◽  
Author(s):  
Frederick M. Hahn ◽  
Anthony P. Hurlburt ◽  
C. Dale Poulter

ABSTRACT Isopentenyl diphosphate isomerase catalyzes the interconversion of isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). In eukaryotes, archaebacteria, and some bacteria, IPP is synthesized from acetyl coenzyme A by the mevalonate pathway. The subsequent isomerization of IPP to DMAPP activates the five-carbon isoprene unit for subsequent prenyl transfer reactions. In Escherichia coli, the isoprene unit is synthesized from pyruvate and glyceraldehyde-3-phosphate by the recently discovered nonmevalonate pathway. An open reading frame (ORF696) encoding a putative IPP isomerase was identified in the E. coli chromosome at 65.3 min. ORF696 was cloned into an expression vector; the 20.5 kDa recombinant protein was purified in three steps, and its identity as an IPP isomerase was established biochemically. The gene for IPP isomerase, idi, is not clustered with other known genes for enzymes in the isoprenoid pathway. E. coli FH12 was constructed by disruption of the chromosomal idi gene with the aminoglycoside 3′-phosphotransferase gene and complemented by the wild-type idi gene on plasmid pFMH33 with a temperature-sensitive origin of replication. FH12/pFMH33 was able to grow at the restrictive temperature of 44°C and FH12 lacking the plasmid grew on minimal medium, thereby establishing thatidi is a nonessential gene. Although theV max of the bacterial protein was 20-fold lower than that of its yeast counterpart, the catalytic efficiencies of the two enzymes were similar through a counterbalance inKm s. The E. coli protein requires Mg2+ or Mn2+ for activity. The enzyme contains conserved cysteine and glutamate active-site residues found in other IPP isomerases.


2000 ◽  
Vol 353 (1) ◽  
pp. 59-67 ◽  
Author(s):  
Narciso CAMPOS ◽  
Manuel RODRÍGUEZ-CONCEPCIÓN ◽  
Susanna SAURET-GÜETO ◽  
Francesca GALLEGO ◽  
Luisa-María LOIS ◽  
...  

Isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP) constitute the basic building block of isoprenoids, a family of compounds that is extraordinarily diverse in structure and function. IPP and DMAPP can be synthesized by two independent pathways: the mevalonate pathway and the recently discovered 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway. Although the MEP pathway is essential in most eubacteria, algae and plants and has enormous biotechnological interest, only some of its steps have been determined. We devised a system suitable for the genetic analysis of the MEP pathway in Escherichia coli. A synthetic operon coding for yeast 5-diphosphomevalonate decarboxylase, human 5-phosphomevalonate kinase, yeast mevalonate kinase and E. coli isopentenyl diphosphate isomerase was incorporated in the chromosome of this bacterium. The expression of this operon allowed the synthesis of IPP and DMAPP from mevalonate added exogenously and complementation of lethal mutants of the MEP pathway. We used this system to show that the ygbP, ychB and ygbB genes are essential in E. coli and that the steps catalysed by the products of these genes belong to the trunk line of the MEP pathway.


2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Quentin M Dudley ◽  
Connor J Nash ◽  
Michael C Jewett

Abstract Isoprenoids are an attractive class of metabolites for enzymatic synthesis from renewable substrates. However, metabolic engineering of microorganisms for monoterpenoid production is limited by the need for time-consuming, and often non-intuitive, combinatorial tuning of biosynthetic pathway variations to meet design criteria. Towards alleviating this limitation, the goal of this work was to build a modular, cell-free platform for construction and testing of monoterpenoid pathways, using the fragrance and flavoring molecule limonene as a model. In this platform, multiple Escherichia coli lysates, each enriched with a single overexpressed pathway enzyme, are mixed to construct the full biosynthetic pathway. First, we show the ability to synthesize limonene from six enriched lysates with mevalonate substrate, an adenosine triphosphate (ATP) source, and cofactors. Next, we extend the pathway to use glucose as a substrate, which relies on native metabolism in the extract to convert glucose to acetyl-CoA along with three additional enzymes to convert acetyl-CoA to mevalonate. We find that the native E. coli farnesyl diphosphate synthase (IspA) is active in the lysate and diverts flux from the pathway intermediate geranyl pyrophospahte to farnesyl pyrophsophate and the byproduct farnesol. By adjusting the relative levels of cofactors NAD+, ATP and CoA, the system can synthesize 0.66 mM (90.2 mg l−1) limonene over 24 h, a productivity of 3.8 mg l−1 h−1. Our results highlight the flexibility of crude lysates to sustain complex metabolism and, by activating a glucose-to-limonene pathway with 9 heterologous enzymes encompassing 20 biosynthetic steps, expands an approach of using enzyme-enriched lysates for constructing, characterizing and prototyping enzymatic pathways.


2016 ◽  
Vol 11 (9) ◽  
pp. 1934578X1601100 ◽  
Author(s):  
Takahiro Kato ◽  
Jung-Bum Lee ◽  
Futoshi Taura ◽  
Fumiya Kurosaki

Two genes involved in δ-guaiene biosynthesis in Aquilaria microcarpa, δ-guaiene synthase (GS) and farnesyl diphosphate synthase (FPS), were overexpressed in Escherichia coli cells. Immunoblot analysis revealed that the concentration of GS-translated protein was rather low in the cells transformed by solely GS while appreciable accumulation of the recombinant protein was observed when GS was coexpressed with FPS GS-transformed cells liberated only a trace amount of δ-guaiene (0.004 μg/mL culture), however, the concentration of the compound elevated to 0.08 μg/mL culture in the cells transformed by GS plus FPS δ-Guaiene biosynthesis was markedly activated when E. coli cells coexpressing GS and FPS were incubated in enriched Terrific broth, and the content of the compound increased to approximately 0.6 μg/mL culture. These results suggest that coexpression of FPS and GS in E. coli is required for efficient 6-guaiene production in the bacterial cells, and the sesquiterpene-producing activity of the transformant is appreciably enhanced in the nutrients-enriched medium.


Author(s):  
Min Jae Kim ◽  
Myung Hyun Noh ◽  
Sunghwa Woo ◽  
Hyun Gyu Lim ◽  
Gyoo Yeol Jung

Microbial production is a promising method that can overcome major limitations in conventional methods of lycopene production, such as low yields and variations in product quality. Significant efforts have been made to improve lycopene production by engineering either the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway or mevalonate (MVA) pathway in microorganisms. To further improve lycopene production, it is critical to utilize metabolic enzymes with high specific activities. Two enzymes, 1-deoxy-D-xylulose-5-phosphate synthase (Dxs) and farnesyl diphosphate synthase (IspA), are required in lycopene production using MEP pathway. Here, we evaluated the activities of Dxs and IspA of Vibrio sp. dhg, a newly isolated and fast-growing microorganism. Considering that the MEP pathway is closely related to the cell membrane and electron transport chain, the activities of the two enzymes of Vibrio sp. dhg were expected to be higher than the enzymes of E. coli. We found that Dxs and IspA in Vibrio sp. dhg exhibited 1.08-fold and 1.38-fold higher catalytic efficiencies, respectively. Consequently, the heterologous overexpression improved the specific lycopene production by 1.88-fold. Our findings could be widely utilized to enhance production of lycopene and other carotenoids.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Xiaomin Wu ◽  
Guang Ma ◽  
Chuanyang Liu ◽  
Xin-yuan Qiu ◽  
Lu Min ◽  
...  

Abstract Background Pinene is a monoterpene, that is used in the manufacture of fragrances, insecticide, fine chemicals, and renewable fuels. Production of pinene by metabolic-engineered microorganisms is a sustainable method. Purple non-sulfur photosynthetic bacteria belong to photosynthetic chassis that are widely used to synthesize natural chemicals. To date, researches on the synthesis of pinene by purple non-sulfur photosynthetic bacteria has not been reported, leaving the potential of purple non-sulfur photosynthetic bacteria synthesizing pinene unexplored. Results Rhodobacter sphaeroides strain was applied as a model and engineered to express the fusion protein of heterologous geranyl diphosphate synthase (GPPS) and pinene synthase (PS), hence achieving pinene production. The reaction condition of pinene production was optimized and 97.51 μg/L of pinene was yielded. Then, genes of 1-deoxy-d-xylulose 5-phosphate synthase, 1-deoxy-d-xylulose 5-phosphate reductoisomerase and isopentenyl diphosphate isomerase were overexpressed, and the ribosome binding site of GPPS-PS mRNA was optimized, improving pinene titer to 539.84 μg/L. Conclusions In this paper, through heterologous expression of GPPS-PS, pinene was successfully produced in R. sphaeroides, and pinene production was greatly improved by optimizing the expression of key enzymes. This is the first report on pinene produce by purple non-sulfur photosynthetic bacteria, which expands the availability of photosynthetic chassis for pinene production.


Sign in / Sign up

Export Citation Format

Share Document