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Volume 6, Issue 8 (Suppl) J Biotechnol Biomater
ISSN: 2155-952X JBTBM, an open access journal Bio America 2016
November 28-30, 2016
November 28-30, 2016 San Francisco, USA
13th Biotechnology Congress
Miyu Nishiguchi et al., J Biotechnol Biomater 2016, 6:8(Suppl)
Ergothioneine fermentative production in Escherichia coli
Miyu Nishiguchi1, Naoyuki Tanaka2, Yusuke Kawano2, Yasuharu Satoh3, Tohru Dairi3 and Iwao Ohtsu2
1Nara Institute of Science and Technology, Japan
2University of Tsukuba, Japan
3Hokkaido University, Japan
Ergothioneine (ERG) is sulfur-containing amino acid synthesized by certain bacteria and fungi. Recently, findings point to critical
functions in human physiology. Human takes ERG from food and concentrates it in specific tissues or cells such as liver, kidney,
central nervous system and red blood cells. ERG is marketed as dietary supplement or nutraceutical so that acts as anti-oxidant. It has
been recognized that filamentous fungi or actinomycetes produce ERG. However, in 2010, the ERG biosynthetic gene was identified
for the first time. Here, we challenged to produce ERG from glucose with our constructed cysteine producer. E. coli has a regulation
system that synthesized cysteine from energetically-favored thiosulfate, as the assimilation of sulfate spends 2 ATP and 4 NADPH.
This cysteine producer produces 16 g/L of cysteine from thiosulfate. Therefore, we established world-first ERG fermentation and
challenged production of much cheaper ERG. We cloned ERG biosynthetic genes from Mycobacterium smegmatis and performed
heterologous expression of cloning ERG genes in E. coli. The analysis of the culture medium by LC-MS/MS detected ERG peak. When
a plasmid carrying these ERG biosynthetic genes was introduced into cysteine producer with enhanced biosynthesis, weakened
degradation and improved export of L-cysteine, the transformants slightly produced ERG into medium from thiosulfate (30 mg/L of
ERG). Interestingly, this transformants produced 200 mg/L of ERG from sulfate. We propose that spending of NADPH is important
for production of ERG.
Biography
Miyu Nishiguchi is currently pursuing Masters in Applied Microbiology at Nara Institute of Science and Technology, Japan.