TY - JOUR
T1 - Ecofriendly Synthesis of l-Carnosine in Metabolically Engineered Corynebacterium glutamicum by Reinforcing Precursor Accumulation
AU - Kim, Minhye
AU - Ko, Young Jin
AU - Jeong, Da Woon
AU - Jeong, Wu Young
AU - Han, Sung Ok
N1 - Funding Information:
This work was supported by the National Research Foundation of Korean (NRF) grant funded by the Korea government (MSIT) (No. 2021R1A2C2006944 and No. 2020M1A2A2080850) and supported by a Korea University Grant.
Publisher Copyright:
© 2021 American Chemical Society.
PY - 2021/6/18
Y1 - 2021/6/18
N2 - Biobased processes to minimize environmental pollutants have attracted much attention. l-Carnosine has been produced by chemical synthesis, and as an alternative to this method, we newly developed engineered Corynebacterium glutamicum synthesizing l-carnosine. To develop the strain, the pentose phosphate pathway (PPP) was enhanced by attenuating flux to nonoxidative PPP. Enhanced PPP strengthened the histidine pathway and produced 5.0 g/L l-histidine and 3.9 mg/L l-carnosine. Then, the histidine synthetic pathway was reinforced by overexpressing HisG and Rel. This pathway reduced feedback inhibition by l-histidine and strengthened the flux of the histidine pathway; thus, it produced 552.20 mg/g DCW l-histidine. As a result, enhancement of the PPP accumulates more l-histidine than the histidine pathway; thus, the PPP was further enhanced by pgi gene alteration. For sufficient β-alanine products, PanD was overexpressed and produced 99.17 mg/L l-carnosine. The final strain, Car15, which consolidated all three pathways, produced 323.26 mg/L l-carnosine via fed-batch fermentation. Finally, we confirmed the antioxidant and antiglycation effects of biologically synthesized l-carnosine, and the biologically synthesized l-carnosine showed inhibitory activity similar to that of commercial l-carnosine. Consequently, this study suggested a new biosynthetic process for l-carnosine and showed potential as a treatment for metabolic disorders through the assessment of its functions.
AB - Biobased processes to minimize environmental pollutants have attracted much attention. l-Carnosine has been produced by chemical synthesis, and as an alternative to this method, we newly developed engineered Corynebacterium glutamicum synthesizing l-carnosine. To develop the strain, the pentose phosphate pathway (PPP) was enhanced by attenuating flux to nonoxidative PPP. Enhanced PPP strengthened the histidine pathway and produced 5.0 g/L l-histidine and 3.9 mg/L l-carnosine. Then, the histidine synthetic pathway was reinforced by overexpressing HisG and Rel. This pathway reduced feedback inhibition by l-histidine and strengthened the flux of the histidine pathway; thus, it produced 552.20 mg/g DCW l-histidine. As a result, enhancement of the PPP accumulates more l-histidine than the histidine pathway; thus, the PPP was further enhanced by pgi gene alteration. For sufficient β-alanine products, PanD was overexpressed and produced 99.17 mg/L l-carnosine. The final strain, Car15, which consolidated all three pathways, produced 323.26 mg/L l-carnosine via fed-batch fermentation. Finally, we confirmed the antioxidant and antiglycation effects of biologically synthesized l-carnosine, and the biologically synthesized l-carnosine showed inhibitory activity similar to that of commercial l-carnosine. Consequently, this study suggested a new biosynthetic process for l-carnosine and showed potential as a treatment for metabolic disorders through the assessment of its functions.
KW - Corynebacterium glutamicum
KW - antioxidant
KW - biobased synthesis
KW - l-carnosine
KW - l-histidine
KW - pentose phosphate pathway
UR - http://www.scopus.com/inward/record.url?scp=85108231350&partnerID=8YFLogxK
U2 - 10.1021/acssynbio.1c00168
DO - 10.1021/acssynbio.1c00168
M3 - Article
C2 - 34019768
AN - SCOPUS:85108231350
SN - 2161-5063
VL - 10
SP - 1553
EP - 1562
JO - ACS Synthetic Biology
JF - ACS Synthetic Biology
IS - 6
ER -