Abstract:
:An integrated approach is used to develop a rapid sampling strategy for the quantitative analysis of in vivo kinetic behavior based on measured concentrations of intracellular metabolites in Saccharomyces cerevisiae. Emphasis is laid on small sample sizes during sampling and analysis. Subsecond residence times are accomplished by minimizing the dead volume of the sterile sampling system and by maximizing flow rates through application of vacuum to the sampling tubes in addition to the overpressure in the fermenter. A specially designed sample tube adapter facilitates sampling intervals of 4 to 5 s for various test tube types. Statistical analysis of the results obtained from enzymatic and liquid chromatography mass spectrometry (LC-MSMS) analysis of the metabolite concentrations was used to optimize the sampling protocol. The most notable improvement is reached through the introduction of vacuum drying of the cell extract. The presented system is capable of reliably dealing with fermenter samples as small as 1-g with a variation of less than 3%, and is thus ideally suited for intracellular measurements on small, lab-scale fermenters.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Lange HC,Eman M,van Zuijlen G,Visser D,van Dam JC,Frank J,de Mattos MJ,Heijnen JJdoi
10.1002/bit.10048subject
Has Abstractpub_date
2001-11-20 00:00:00pages
406-15issue
4eissn
0006-3592issn
1097-0290pii
10.1002/bit.10048journal_volume
75pub_type
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