TY  - JOUR
AU  - Netzer, R.
AU  - Peters-Wendisch, P.
AU  - Eggeling, L.
AU  - Sahm, H.
TI  - Co-metabolism of a Non-Growth Substrate: L-Serine Utilization by Corynebacterium glutamicum
JO  - Applied and environmental microbiology
VL  - 70
SN  - 0099-2240
CY  - Washington, DC [u.a.]
PB  - Soc.
M1  - PreJuSER-36935
SP  - 7148 - 7155
PY  - 2004
N1  - Record converted from VDB: 12.11.2012
AB  - Despite its key position in central metabolism, L-serine does not support the growth of Corynebacterium glutamicum. Nevertheless, during growth on glucose, L-serine is consumed at rates up to 19.4 +/- 4.0 nmol min(-1) (mg [dry weight])(-1), resulting in the complete consumption of 100 mM L-serine in the presence of 100 mM glucose and an increased growth yield of about 20%. Use of 13C-labeled L-serine and analysis of cellularly derived metabolites by nuclear magnetic resonance spectroscopy revealed that the carbon skeleton of L-serine is mainly converted to pyruvate-derived metabolites such as L-alanine. The sdaA gene was identified in the genome of C. glutamicum, and overexpression of sdaA resulted in (i) functional L-serine dehydratase (L-SerDH) activity, and therefore conversion of L-serine to pyruvate, and (ii) growth of the recombinant strain on L-serine as the single substrate. In contrast, deletion of sdaA decreased the L-serine cometabolism rate with glucose by 47% but still resulted in degradation of L-serine to pyruvate. Cystathionine beta-lyase was additionally found to convert L-serine to pyruvate, and the respective metC gene was induced 2.4-fold under high internal L-serine concentrations. Upon sdaA overexpression, the growth rate on glucose is reduced 36% from that of the wild type, illustrating that even with glucose as a single substrate, intracellular L-serine conversion to pyruvate might occur, although probably the weak affinity of L-SerDH (apparent Km, 11 mM) prevents substantial L-serine degradation.
KW  - Bacterial Proteins: genetics
KW  - Bacterial Proteins: metabolism
KW  - Carbon Isotopes: metabolism
KW  - Corynebacterium glutamicum: growth & development
KW  - Corynebacterium glutamicum: metabolism
KW  - Culture Media
KW  - Gene Deletion
KW  - Glucose: metabolism
KW  - L-Serine Dehydratase: genetics
KW  - L-Serine Dehydratase: metabolism
KW  - Magnetic Resonance Spectroscopy
KW  - Oligonucleotide Array Sequence Analysis
KW  - Serine: metabolism
KW  - Bacterial Proteins (NLM Chemicals)
KW  - Carbon Isotopes (NLM Chemicals)
KW  - Culture Media (NLM Chemicals)
KW  - Glucose (NLM Chemicals)
KW  - Serine (NLM Chemicals)
KW  - L-Serine Dehydratase (NLM Chemicals)
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:15574911
C2  - pmc:PMC535176
UR  - <Go to ISI:>//WOS:000225719300026
DO  - DOI:10.1128/AEM.70.12.7148-7155.2004
UR  - https://juser.fz-juelich.de/record/36935
ER  -