Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-8-19
pubmed:abstractText
Monitoring amino acid metabolism during fermentation has significant potential from the standpoint of strain selection, optimizing growth and production in host strains, and profiling microbial metabolism and growth state. A method has been developed based on rapid quantification of underivatized amino acids using liquid chromatography-electrospray tandem mass spectrometry (LC-MS-MS) to monitor the metabolism of 20 amino acids during microbial fermentation. The use of a teicoplanin-based chiral stationary phase coupled with electrospray tandem mass spectrometry allows complete amino acid analyses in less than 4 min. Quantification is accomplished using five isotopically labeled amino acids as internal standards. Because comprehensive chromatographic separation and derivatization are not required, analysis time is significantly less than traditional reversed- or normal-phase LC-based amino acid assays. Intra-sample precisions for amino acid measurements in fermentation supernatants using this method average 4.9% (R.S.D.). Inter-day (inter-fermentation) precisions for individual amino acid measurements range from 4.2 to 129% (R.S.D.). Calibration curves are linear over the range 0-300 microg/ml, and detection limits are estimated at 50-450 ng/ml. Data visualization techniques for constructing semi-quantitative fermentation profiles of nitrogen source utilization have also been developed and implemented, and demonstrate that amino acid profiles generally correlate with observed growth profiles. Further, cellular growth events, such as lag-time and cell lysis can be detected using this methodology. Correlation coefficients for the time profiles of each amino acid measured illustrate that while several amino acids are differentially metabolized in similar fermentations, a select group of amino acids display strong correlations in these samples, indicating a sub-population of analytes that may be most useful for fermentation profiling.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9673
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
1043
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3-7
pubmed:dateRevised
2009-1-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Potential of fermentation profiling via rapid measurement of amino acid metabolism by liquid chromatography-tandem mass spectrometry.
pubmed:affiliation
Scientific Resources Center, Cargill, Inc, Minneapolis, MN 55440-5702, USA. joseph_dalluge@cargill.com
pubmed:publicationType
Journal Article