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

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Expression of glf Z.m. increases D-mannitol formation in whole cell biotransformation with resting cells of Corynebacterium glutamicum.
    Author: Bäumchen C, Bringer-Meyer S.
    Journal: Appl Microbiol Biotechnol; 2007 Sep; 76(3):545-52. PubMed ID: 17503033.
    Abstract:
    A recombinant oxidation/reduction cycle for the conversion of D-fructose to D-mannitol was established in resting cells of Corynebacterium glutamicum. Whole cells were used as biocatalysts, supplied with 250 mM sodium formate and 500 mM D-fructose at pH 6.5. The mannitol dehydrogenase gene (mdh) from Leuconostoc pseudomesenteroides was overexpressed in strain C. glutamicum ATCC 13032. To ensure sufficient cofactor [nicotinamide adenine dinucleotide (reduced form, NADH)] supply, the fdh gene encoding formate dehydrogenase from Mycobacterium vaccae N10 was coexpressed. The recombinant C. glutamicum cells produced D-mannitol at a constant production rate of 0.22 g (g cdw)(-1) h(-1). Expression of the glucose/fructose facilitator gene glf from Zymomonas mobilis in C. glutamicum led to a 5.5-fold increased productivity of 1.25 g (g cdw)(-1) h(-1), yielding 87 g l(-1) D-mannitol from 93.7 g l(-1) D-fructose. Determination of intracellular NAD(H) concentration during biotransformation showed a constant NAD(H) pool size and a NADH/NAD(+) ratio of approximately 1. In repetitive fed-batch biotransformation, 285 g l(-1) D-mannitol over a time period of 96 h with an average productivity of 1.0 g (g cdw)(-1) h(-1) was formed. These results show that C. glutamicum is a favorable biocatalyst for long-term biotransformation with resting cells.
    [Abstract] [Full Text] [Related] [New Search]