Kinetics of growth and leukotoxin production by Mannheimia haemolytica in continuous culture
| Autor: | James C. du Preez, Eugéne van Rensburg, Stephanus G. Kilian |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
chemistry.chemical_classification
Chromatography Exotoxins Bioengineering Metabolism Chemostat Applied Microbiology and Biotechnology Carbon Culture Media Amino acid Dilution Glutamine Kinetics Acetic acid chemistry.chemical_compound Glucose chemistry Yield (chemistry) Sulfites Biomass Amino Acids Mannheimia haemolytica Acetic Acid Biotechnology Cysteine |
| Zdroj: | Journal of Industrial Microbiology & Biotechnology. 35:611-618 |
| ISSN: | 1476-5535 1367-5435 |
| Popis: | The growth and product formation kinetics of the bovine pathogen Mannheimia (Pasteurella) haemolytica strain OVI-1 in continuous culture were investigated. The leukotoxin (LKT) concentration and yield on biomass could substantially be enhanced by supplementation of a carbon-limited medium with an amino acid mixture or a mixture of cysteine and glutamine. Acetic acid was a major product, increasing to 1.66 g l(-1) in carbon-limited chemostat culture at intermediate dilution rates and accounting for more than 80% of the glucose carbon, whereas in amino acid-limited cultures high acetic acid concentrations were produced at low dilution rates, suggesting a carbon-overflow metabolism. The maintenance coefficients of carbon-limited and carbon-sufficient cultures were 0.07 and 0.88 mmol glucose g(-1) h(-1), respectively. LKT production was partially growth-associated and the LKT concentration was maximised to 0.15 g l(-1) and acetic acid production minimised by using a carbon-limited medium and a low dilution rate. |
| Databáze: | OpenAIRE |
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