Coupled incremental precursor and co-factor supply improves 3-hydroxypropionic acid production in Saccharomyces cerevisiae

Functional balance between enzymes in malonyl-CoA pathway for 3-hydroxypropionate biosynthesis

“…The crude enzyme activity was determined at 37°C, pH 7.2 with 10 μg soluble protein extracts based on the similar strategy mentioned above. 3HP concentration in medium was determined by HPLC as described previously (Chen et al, 2014). During the fermentation process, pH was controlled at 7.0 via automated addition of ammonia.…”

“…The malonyl-CoA pathway with whole-length MCR protein has been reconstructed in E. coli and S. cerevisiae, and the yield of 3HP remained low (Chen et al, 2014;Rathnasingh et al, 2012). In our previous work, MCR was dissected into two functional fragments, and 3HP-producing strain Q1319 was constructed using separated MCR-N and MCR-C fragments.…”

Biobased organic acids production by metabolically engineered microorganisms

“…This was achieved by enhancing the availability of malonyl-CoA through attenuation of fatty acid biosynthesis combined with overexpression of the native acetyl-CoA carboxylase gene and improving the carbon flux towards acetyl-CoA through elimination of byproducts such as lactate, ethanol, acetate and methylglyoxal. As this bi-functional malonyl-CoA reductase requires NADPH, improving precursor supply coupled with enhanced redox co-factor has been shown in S. cerevisiae to improve 3-HP production by fivefold, up to 0.46 g/L [35]. Furthermore, increasing NADPH supply by replacement of native NAD dependent glyceraldehyde-3-phosphate dehydrogenase (GAPDH) with exogenous NADP dependent GAPDH, combined with improving metabolic flux towards 3-HP via overexpression of Pdc, Ald, Acs, Acc genes in S. cerevisiae resulted in a 3-HP titer of 9.5 g/L with a yield of 0.09 g/g glucose [36].…”

Advances in Metabolic Engineering of Saccharomyces cerevisiae for the Production of Industrially and Clinically Important Chemicals

“…Although there are biological pathways to 3-HP via either glycerol, lactate, malonyl-CoA or β-alanine intermediates, no organism is known to produce it as an end product [22]. The pathways based on malonyl-CoA and β-alanine have been constructed in S. cerevisiae [23,24]. Chen et al evaluated diferent malonyl-CoA reductases.…”

“…The cellular concentration of malonyl-CoA was increased by over-expression of ACC1 (acetyl-CoA carboxylase), which is the sole enzyme in the conversion of acetyl-CoA to malonyl-CoA. Finally, 3-HP was produced at a titer of 463 mg/L when the production was coupled with enhanced supply of electron donor of MCR Ca (NADPH) by heterologous expression of GAPNp (a non-phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Streptococcus mutans) [23]. In another study, a signiicant improvement of 3-HP production was achieved when multiple copies of MCR were integrated Advances in Metabolic Engineering of Saccharomyces cerevisiae for the Production... http://dx.doi.org/10.5772/intechopen.70327…”