Suppression of lactate production by aerobic fed-batch cultures of Lactococcus lactis
Aerobic fed-batch cultures were studied as a means of suppressing the production of lactate, which inhibits the growth of lactic acid bacteria (LAB). LAB produce lactate via lactate dehydrogenase (LDH), regenerating nicotinamide adenine dinucleotide (NAD+) consumed during glycolysis. Therefore, we f...
Saved in:
| Published in: | Journal of bioscience and bioengineering Vol. 130; no. 4; pp. 402 - 408 |
|---|---|
| Main Authors: | , , , , , |
| Format: | Journal Article |
| Language: | English |
| Published: |
Elsevier B.V
01-10-2020
|
| Subjects: | |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Aerobic fed-batch cultures were studied as a means of suppressing the production of lactate, which inhibits the growth of lactic acid bacteria (LAB). LAB produce lactate via lactate dehydrogenase (LDH), regenerating nicotinamide adenine dinucleotide (NAD+) consumed during glycolysis. Therefore, we focused on NADH oxidase (NOX), employing oxygen as an electron acceptor, as an alternative pathway to LDH for NAD+ regeneration. To avoid glucose repression of NOX and NAD+ consumption by glycolysis exceeding NAD+ regeneration by NOX, glucose was fed gradually. When Lactococcus lactis MG 1363 was aerobically fed at a specific growth rate of 0.2 h−1, the amount of lactate produced per amount of grown cell was reduced to 12% of that in anaerobic batch cultures. Metabolic flux analysis revealed that in addition to NAD+ regeneration by NOX, ATP acquisition by production of acetate and NAD+ regeneration by production of acetoin and 2,3-butanediol contributed to suppression of lactate production. |
|---|---|
| Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
| ISSN: | 1389-1723 1347-4421 |
| DOI: | 10.1016/j.jbiosc.2020.06.004 |