These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Spectrophotometric assay for sensitive detection of glycerol dehydratase activity using aldehyde dehydrogenase.
    Author: Park ES, Park S, Shin JS.
    Journal: J Biosci Bioeng; 2017 Apr; 123(4):528-533. PubMed ID: 28052817.
    Abstract:
    Glycerol dehydratase (GDHt) is a pivotal enzyme for fermentative utilization of glycerol by catalyzing radical-mediated conversion of glycerol into 3-hydroxypropionaldehyde (3-HPA). Precise and sensitive monitoring of cellular GDHt activity during the fermentation process is a prerequisite for reliable metabolic analysis to afford efficient cellular engineering and process optimization. Here we report a new spectrophotometric assay for the sensitive measurement of the GDHt activity with a sub-nanomolar limit of detection (LOD). The assay method employs aldehyde dehydrogenase (ALDH) as a reporter enzyme, so the readout of the GDHt activity is recorded at 340 nm as an increase in UV absorbance which results from NADH generation accompanied by oxidation of 3-HPA to 3-hydroxypropionic acid (3-HP). The GDHt assay was performed under the reaction conditions where the ALDH activity overwhelms the GDHt activity (i.e., 50-fold higher activity of ALDH relative to GDHt activity), affording sensitive detection of GDHt with 360 pM LOD. The ALDH-coupled assay was used to determine kinetic parameters of GDHt for glycerol, leading to KM = 0.73 ± 0.09 mM and kcat = 400 ± 20 s-1 which are in reasonable agreements with the previous reports. Our assay method allowed measurement of even a 104-fold decrease in the cellular GDHt activity during fermentative production of 3-HP, which demonstrates the detection sensitivity much higher than the previous methods.
    [Abstract] [Full Text] [Related] [New Search]