Effects of varying media, temperature, and growth rates on the intracellular concentrations of yeast amino acids

• Published in: Biotechnology progress 1995-07, Vol.11 (4), p.386-392
• Main Authors: Martinez-Force, E. (Case Western Reserve University, Cleveland, OH.), Benitez, T
• Format: Article
• Language: English
• Subjects: ACIDE AMINE; AMINO ACIDS; Amino Acids - metabolism; AMINOACIDOS; Biological and medical sciences; Biology of microorganisms of confirmed or potential industrial interest; Biotechnology; CELL CULTURE; CHAMPIGNON; CULTIVO DE CELULAS; CULTURE DE CELLULE; CULTURE MEDIA; DISPONIBILIDAD DE NUTRIENTES; DISPONIBILITE D'ELEMENT NUTRITIF; Fermentation - physiology; FREE AMINO ACIDS; FRUCTOSA; FRUCTOSE; Fundamental and applied biological sciences. Psychology; Fungal Proteins - metabolism; FUNGI; GLICEROL; GLUCOSA; GLUCOSE; Glucose - metabolism; GLYCEROL; HONGOS; Hydrogen-Ion Concentration; LEVADURA; LEVURE; MEDIO DE CULTIVO; MELASSE; MELAZA; METABOLISM; METABOLISME; METABOLISMO; MILIEU DE CULTURE; Mission oriented research; MOLASSES; NUTRIENT AVAILABILITY; Physiology and metabolism; PROTEINAS UNICELULARES; PROTEINE MICROBIOLOGIQUE; Saccharomyces; SACCHAROMYCES CEREVISIAE; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - metabolism; SACCHAROSE; SINGLE CELL PROTEIN; SUCROSA; SUCROSE; TEMPERATURA; TEMPERATURE; YEASTS
• ISSN: 8756-7938; 1520-6033
• DOI: 10.1021/bp00034a004

Variations of the yeast free amino acid pool under different culture conditions were studied in two Saccharomyces strains, the laboratory haploid strain S288C and the industrial fermentative yeast IFI256. The internal amino acid pool of both strains was measured when grown in laboratory (minimal and complete) versus semiindustrial (molasses with or without added biotin and/or diammonium phosphate) media, in fermentable (glucose, fructose, sucrose) versus respirable (glycerol) carbon sources, in different temperatures (22, 30, and 37 °C), pHs (2. 0–4.75), and growth rates (0. 018–0.24 h−1) in continuous culture, and at different phases of the growth curve in batch culture (lag, exponential, early and late stationary). Results indicated that environmental conditions, particularly the presence of amino acids in the media, enormously influenced the intracellular amino acid concentration. Higher values were detected in molasses than in laboratory media and in fermentable carbon sources (glucose, fructose, sucrose) than in glycerol. Variations in the amino acid pool along the growth curve were greater at 37 °C than at other temperatures; in all cases, the highest values were measured at the begining of the exponential phase. In continuous culture and at different growth rates, intracellular free amino acid concentrations increased by 3–10‐fold when the growth rate was lower than 0.05 h−1, representing 20–35% of the total (free plus protein) amino acid content and indicating that amino acid yield was a partly growth‐linked parameter.