Casamino acids

Bacteria in thawed ice samples from Ellesmere Island (79°38 N, 74°23 W) produced CO2 and CH4 during extended incubation at 4°C in a diluted complex medium (yeast extract, casamino acids, starch, and glucose) (Skidmore et al. 2000). It was suggested that the results demonstrated that the subglacial environment beneath a polythermal glacier provided an acceptable habitat for microbial life. 

Vitamins such as thiamin, biotin, and vitamin Bj2 are often added. Once again, the requirements of anaerobes are somewhat greater, and a more extensive range of vitamins that includes pantothenate, folate, and nicotinate is generally employed. In some cases, additions of low concentrations of peptones, yeast extract, casamino acids or rumen fluid may be used, though in higher concentrations, metabolic ambiguities may be introduced since these compounds may serve as additional carbon sources. 

In highly saline brines, which were collected from the Vassar Vertz Sand Unit, Pajme County, Oklahoma, diverse populations of anaerobic, heterotrophic bacteria were present. All strains grew in a mineral salts medium containing glucose, yeast extract, and casamino acids in the presence of NaCl concentrations of up to 20% by weight [177],... 

Within our laboratory we have shown that using the combination of PyMS and ANNs it is possible to follow the production of indole in a number of strains of E. coli grown on media incorporating various amounts of tryptophan,98 and to estimate the amount of casamino acids in mixtures with glycogen.99 It was also shown that it is possible to quantify the (bio)chemical constituents of complex binary mixtures of proteins and nucleic acids in glycogen, and to measure the concentrations of binary and tertiary mixtures of Bacillus subtilis, Escherichia coli, and Staphylococcus aureus.93,100... 

Goodacre, R. Edmonds, A. N. Kell, D. B. Quantitative analysis of the pyrolysis mass spectra of complex mixtures using artificial neural networks—Application to casamino acids in glycogen. J. Anal. Appl. Pyrolysis 1993, 26, 93-114. 

Salt-free hydrochloric acid hydrolyzate of casein, Baltimore Biological Laboratory Inc., Baltimore, Maryland. These casein hydrolyzates can be substituted by Casamino acid (Difco), enzymatically hydrolyzed casein or acid-hydrolyzed casein. 

Cells (C), or supernatant liquor (S). b YCV, Yeast nitrogen base-Casamino acids-Vitamins. M, Synthetic medium. d BHI, Brain-heart infusion. Sab, Sabouraud.1 B, Mariat s medium. 

Amino acids (Factor B, experiment 1) were supplied as casein peptone 35 g/L (Marcor) or casamino acids 25.8 g/L (Marcor). 

Example number 1. Medium for fermentation. The goal of this experiment was to develop a defined fermention medium that was usable for the manufacture of ImuVert The objectives were to evaluate the effect of replacing citrate with a phosphate buffer, yeast extract with vitamins and minerals, casamino acids with casein peptone and high or low O2 levels on the final yield and composition of ImuVert. 

Figure 1. Half Effect Results for Yield (A) or Vesicle to Ribosome Ratio (B). A is the effect of vitamins and yeast extract. B is the effect of casein peptone and casamino acids. C is the effect of dissolved O2. D is the effect of citrate and phosphate. AB is the interaction of yeast extractAdtamin and mineral with casein peptone/casamino acids. AC is the interaction of yeast extractAdtamins and minerals with dissolved O2. BC is the interaction of casein peptone/casamino acids with dissolved O2. CD is the interaction effect of dissolved 2 with the citrate or phosphate.

When required, media were supplemented with casamino acids (Difco, Detroit, MI) to a final concentration of 5 g/L. Four different media were tested hydrolysate (H), supplemented hydrolysate (SH), concentrated hydrolysate (CH), and concentrated and supplemented hydrolysate (CSH). To prevent additional medium decomposition, all media were filter sterilized using 0.22 pm Gelman membrane filters (Pall, Ann Arbor, MI). 

Fig. 2. Time course of substrate, cell dry weight, and fermentation products in fermentation of casamino acids supplemented with BSG OCL posthydrolysate (SH medium) (A) and casamino acids supplemented concentrated posthydrolysate (CSH medium) (B) by D. hansenii CCMI 941. ( ) Glucose, (O) xylose, (A) arabinose, ( ) cell dry weight, ( ) ethanol, ( ) xylitol, and (A) arabitol.

The major change in yeast metabolism induced by casamino acids supplementation was the marked increase in xylitol production, being the major metabolic product by D. hansenii grown in supplemented concentrated medium (Fig. 2B). Both arabitol and xylitol production in yeast are described to be augmented under stress conditions. Arabitol is usually found as a product of arabinose metabolism in oxygen-limited conditions (8,22), but arabitol production is not restricted to arabinose metabolism,... 

H, hydrolysate CH, concentrated hydrolysate SH, casamino acids-supplemented hydrolysate CSH, concentrated and supplemented hydrolysate. 

NZC medium 9 g NZ amine (Gibco BRL, Grand Island, NY), 4.5 g NaCl, 4.5 g casamino acids, water to 0.9 liter mix, then autoclave... 

NZC bottom agar 10 g NZ amine, 5 g NaCl, 5 g casamino acids, 15 g agar, water to 1 liter... 

Several analogs of TP at 1500 ppm cause a growth lag of 25-50 hrs of E. coli (K-12) growing in minimal media. The growth lag was completely abolished with the addition of casamino acids or a mixture of... 

Curve 2 0.4% Casamino acids (vitamin-free, Bacto) added Curve 3 0.4% Casamino acids and 0.4% yeast extract added Curve 4 0.4% Casamino acids added and vitamin mixture (Table II) deleted Data indicate means of three tubes... 

Yong, L.F.M. and Kok, M.-F. The Effect of Casamino Acids and Glucose Concentrations on Linalool Production by PeniciUium itahcum. In Food Flavors, Ingredients and Composition (Charalambous, G., ed.). Amsterdam, Elsevier, pp. 745-751 (1993)... 

Constituent Peptone Tryptone Casamino Acids Yeast Extract... 

The protocol outlined by the American Society for Testing Materials (ASTM) was followed for the solid surface growth studies. A film of the polymer was cast on the surface of a BMS-agar plate by spreading 2.0 ml of 10 mg/ml poly(ester-urethane) in THF over the surface of the plate and evaporating the THF. The centers of the plates were inoculated with 0.1 ml of the spore suspensions or 0.1 ml of a turbid culture of yeast grown on 0.2% (w/v) Casamino Acids (Difco, Detroit, Ml), after which the plates were incubated at 25 C for one month. 

SD-CAA selective growth media. Dissolve 26.7g of 2% dextrose dropout base powder (Q-Biogene cat 4025-012), 5g Bacto casamino acids (lacks adenosine, uracil and tryptophan) (Becton Dickinson cat 223050), 10.19g Na2HPO4-7H20 and 8.56g NaH2PO4-H20, in dH20 to 1 L and sterilize by filtration (pH 6.5). 

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