| Value |
60.4
%
Range: ±0.2 Table - link %
|
| Organism |
Budding yeast Saccharomyces cerevisiae |
| Reference |
Illmer P, Erlebach C, Schinner F. A practicable and accurate method to differentiate between intra- and extracellular water of microbial cells. FEMS Microbiol Lett. 1999 Sep 1 178(1):135-9. p.138 table 1PubMed ID10483732
|
| Method |
P.136 right column 3rd & 4th paragraphs: "An infra-red balance (Mettler LP16) which was interfaced to a computer was used for the investigation. Weight was measured automatically every 6 s till no further change in weight could be recognised (about 40 min after starting). The basic assumption of the method is that drying of microbial cells occurs during two phases (Fig. 1). First, the more volatile extracellular water We is lost. Not before this fraction is completely evaporated, the intracellular water Wi starts to vaporise. The change between the two phases (the so-called critical point, CP) can be detected in the form of a small bulge. This change in drying behaviour should be caused by the membrane and/or the cell wall as this briefly protects Wi against evaporation...[Researchers] used the second derivation (f"(x)) to determine the CP. As can be deduced from Fig. 1, the CP must be located between two inflection points (f"(x)=0) and should be characterised by a minimum of f"(x) which indicates a minimum radius of curvature of the original curve." See primary source [7] [Uribelarrea, J.L., Pacaud, S., Goma, G. (1985) New method for measuring the cell water content by thermogravimetry. Biotechnol. Lett. 7, 75–80] for more details of method. |
| Comments |
P.137 left column bottom paragraph: "Wi values relative to DM [dry matter] of S. cerevisiae and Arthrobacter sp. are given in Table 1. Percentages of DM per g of fresh weight are not presented as these values vary to a great extent depending mainly on the sample preparation. However, the total water contents are about 10% higher than the more exact data given in Table 1 and thus correspond better with data from literature, where usually no differentiation between intra- and extracellular water is made [refs 1,2]." P.138 left column top paragraph: "From [primary source 7, see bottom of Method], the Wi of S. cerevisiae was calculated to be 1.1 g/g DM which is beyond the results shown in Table 1. However, growth conditions (nutrition, incubation time and temperature) differ from the ones used within the present investigation and may therefore be responsible for the difference [ref 9]. Quiros et al. ([ref 3]) calculated the Wi of Streptomyces antibioticus to be 0.81 and 1.56 ml/g DM for dormant spores and vegetative mycelium, respectively. This again indicates the great variability depending on the stage of growth even within a species." For water fraction by volume in E. coli, yeast and mammalian cell see BNID 100044, 105094, 103960, respectively |
| Entered by |
Uri M |
| ID |
103689 |