Characterization of salt-tolerant mutant for enhancement of l -threonine production in Escherichia coli
| Autor: | Hyune-Hwan Lee, Kyung-Hwa Song, Hyung-Hwan Hyun |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Threonine
Proline Mutant Salt (chemistry) Sodium Chloride Biology medicine.disease_cause Applied Microbiology and Biotechnology Escherichia coli medicine Food science chemistry.chemical_classification Strain (chemistry) General Medicine biology.organism_classification Enterobacteriaceae Culture Media Kinetics Glucose chemistry Biochemistry Fermentation Mutation Bacteria Biotechnology |
| Zdroj: | Applied Microbiology and Biotechnology. 54:647-651 |
| ISSN: | 1432-0614 0175-7598 |
| DOI: | 10.1007/s002530000417 |
| Popis: | Escherichia coli strain HS3, metabolically engineered to have Met(-), AHV(r), Ile(L) and AEC(r) characteristics, produced 58.0 g/l of L-threonine, but it was neither salt-tolerant nor osmotolerant; and the growth and threonine production of the strain were severely inhibited both by the addition of NaCl with a concentration higher than 2% and by the presence of glucose with a concentration higher than 10%. Therefore, salt-tolerant mutants were isolated. The salt-tolerant mutants, HS454 and HS528 which were derived from strain HS3, were both tolerant to salt (2%) and hyper-productive. The growth and L-threonine production by the mutant strain HS454 were almost unaffected by a glucose concentration lower than 10%, but gradually reduced with increasing glucose concentration, up to 15%. However, the mutant strain HS528 showed slightly enhanced growth and L-threonine production with increasing glucose concentration, up to 10-12.5%. Strains HS454 and HS528 produced 69.8 g/l and 74.0 g/l of L-threonine, respectively in a 5-1 jar fermentor. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink