Genetic engineering of Escherichia coli for production of tetrahydrobiopterin

Engineering of l-tyrosine oxidation in Escherichia coli and microbial production of hydroxytyrosol

“…2A) (Smith, 1987;Takikawa et al, 1986;Thony et al, 2000;Yamamoto et al, 2003). Even though the biosynthesis of BH4 in E. coli has been reported previously using a heterologous pathway (Yamamoto et al, 2003), we were not able to clone and express the SR gene in E. coli despite many attempts. This failure motivated us to (Ikemoto et al, 2002;Pribat et al, 2010).…”

“…BH4 biosynthesis requires two heterologous enzymes in addition to the endogenous GTP cyclohydrolase (FolE), which produces 7,8-dihydroneopterin triphosphate (H2-NPt-P3) from GTP: the 6-pyruvoyl-tetrahydropterin synthase (PTPS) catalyzes the conversion of H2-NPt-P3 to 6-pyruvoyltetrahydropterin (P-H4-Pt), and sepiapterin reductase (SR) performs the two-step reduction of the diketo intermediate P-H4-Pt to BH4 ( Fig. 2A) (Smith, 1987;Takikawa et al, 1986;Thony et al, 2000;Yamamoto et al, 2003). Even though the biosynthesis of BH4 in E. coli has been reported previously using a heterologous pathway (Yamamoto et al, 2003), we were not able to clone and express the SR gene in E. coli despite many attempts.…”

Enhancing GDP-fucose production in recombinant Escherichia coli by metabolic pathway engineering

“…In addition to GDP-fucose, the modulation schemes of guanosine nucleotide biosynthesis in this work could also be used as references to improve the production of other bioactive substances, such as GDP-mannose [29,30], riboflavin [31,32] and tetrahydrobiopterin [33], biosynthesis of which also requires GTP as a precursor. With this optimal scheme, the GDP-fucose productivity was further improved by fed-batch fermentation to a maximum value of 6.6 ± 0.14 mol/g DCM, which corresponds to 3.9 mg/g DCM if GDP-fucose is presumed to exist as free acid (C 16 H 25 N 5 O 15 P 2 , Mw 589.34) and 4.2 mg/g DCM if existing as disodium salt as the commercial obtained GDP-fucose standard (C 16 H 23 N 5 Na 2 O 15 P 2 , Mw 633.31).…”

Biosynthesis of 7-Deazaguanosine-Modified tRNA Nucleosides: a New Role for GTP Cyclohydrolase I

“…In mammals, GCYH-I is under negative-feedback inhibition through interactions with the GCYH feedback reg- VOL. 190, 2008 PRE-Q 0 BIOSYNTHESIS 7881 on May 11, 2018 by guest http://jb.asm.org/ ulatory protein (24), but this is not observed in bacteria as they lack this protein, and the overexpression of folate or BH4 biosynthetic genes results in overproduction of the final products (52,57). In E. coli, the expression of the folE gene has been shown to be under the control of the negative regulator MetJ (30).…”