Abstract
The effects of fumarase inhibitor cycloheximide on fermentation of L-malic acid and fumaric acid by Rhizopus oryzae ME-M15 were investigated. The results showed that the addition of cycloheximide (15 mg/L) during the acid production stage after 16 h incubation greatly affected the metabolism of Rhizopus oryzae ME-M15. The activity of cytosolic isoenzyme of fumarase was decreased markedly by 48.7%, but the activity of NAD-malate dehydrogenase in the cytosol fraction did not change significantly in the presence of cycloheximide. Fumaric acid production was severely decreased in the presence of cycloheximide with 37.1% in comparison with the control mycelium. In contrast to the inhibitory effect of fumaric acid fermentation, the addition of cycloheximide caused the increase of L-malic acid accumulation to 21.7 g/L, which was 54.6% higher than that of the control. The analyses revealed that the inhibition of fumarase isoenzyme in the cytosol fraction could reduce the metabolic flux from L-malic acid to fumaric acid in the pyruvate carboxylation pathway (cytosolic pathway), promoting the L-malic acid accumulation by Rhizopus oryzae ME-M15.
| Original language | English |
|---|---|
| Pages (from-to) | 153-156 |
| Number of pages | 4 |
| Journal | Guocheng Gongcheng Xuebao/The Chinese Journal of Process Engineering |
| Volume | 9 |
| Issue number | 1 |
| State | Published - Feb 2009 |
Keywords
- Cycloheximide
- Fumarase
- Fumaric acid
- L-malic acid
- Rhizopus oryzae