Batch kinetics of Corynebacterium glutamicum during growth on various carbon substrates: use of substrate mixtures to localise metabolic bottlenecks

Cocaign, Muriel; Monnet, Christophe; Lindley, Nic D.

doi:10.1007/bf00175743

Cited by 49 publications

(36 citation statements)

References 8 publications

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“…3B and D). The simultaneous consumption of two substrates and the monophasic growth of C. glutamicum with glucose or other sugars and with glucose and additional organic acids, such as lactate, pyruvate, acetate, and propionate, were shown previously (18,20,23,32,47,54,56,69,75). Diauxic growth and the sequential utilization of carbon sources by C. glutamicum have been described only for mixtures of glucose and glutamate (45,48) and for mixtures of glucose and ethanol (3,4,44).…”

Section: Discussionmentioning

confidence: 99%

Arabitol Metabolism of Corynebacterium glutamicum and Its Regulation by AtlR

Laslo

Zaluskowski

Gabris

et al. 2011

Journal of Bacteriology

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Expression profiling of Corynebacterium glutamicum in comparison to a derivative deficient in the transcriptional regulator AtlR (previously known as SucR or MtlR) revealed eight genes showing more than 4-fold higher mRNA levels in the mutant. Four of these genes are located in the direct vicinity of the atlR gene, i.e., xylB, rbtT, mtlD, and sixA, annotated as encoding xylulokinase, the ribitol transporter, mannitol 2-dehydrogenase, and phosphohistidine phosphatase, respectively. Transcriptional analysis indicated that atlR and the four genes are organized as atlR-xylB and rbtT-mtlD-sixA operons. Growth experiments with C. glutamicum and C. glutamicum ⌬atlR, ⌬xylB, ⌬rbtT, ⌬mtlD, and ⌬sixA derivatives with sugar alcohols revealed that (

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Section: Discussionmentioning

confidence: 99%

Arabitol Metabolism of Corynebacterium glutamicum and Its Regulation by AtlR

Laslo

Zaluskowski

Gabris

et al. 2011

Journal of Bacteriology

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“…In contrast to the growth of C. glutamicum on many substrate mixtures, such as glucose plus acetate, lactate, pyruvate, or fructose (7,12,52), the growth of this organism on a mixture of glucose and ethanol is biphasic, with glucose consumption in the first and ethanol consumption in the second exponential growth phase (3). This biphasic growth behavior is probably due to relatively low ADH and ALDH activities in the first and much higher ADH and ALDH activities (and thus, high ethanol oxidation activity) in the second growth phase (3).…”

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confidence: 98%

The Alcohol Dehydrogenase Gene adhA in Corynebacterium glutamicum Is Subject to Carbon Catabolite Repression

Arndt

Eikmanns

2007

J Bacteriol

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Corynebacterium glutamicum has recently been shown to grow on ethanol as a carbon and energy source and to possess high alcohol dehydrogenase (ADH) activity when growing on this substrate and low ADH activity when growing on ethanol plus glucose or glucose alone. Here we identify the C. glutamicum ADH gene (adhA), analyze its transcriptional organization, and investigate the relevance of the transcriptional regulators of acetate metabolism RamA and RamB for adhA expression. Sequence analysis of adhA predicts a polypeptide of 345 amino acids showing up to 57% identity with zinc-dependent ADH enzymes of group I. Inactivation of the chromosomal adhA gene led to the inability to grow on ethanol and to the absence of ADH activity, indicating that only a single ethanol-oxidizing ADH enzyme is present in C. glutamicum. Transcriptional analysis revealed that the C. glutamicum adhA gene is monocistronic and that its expression is repressed in the presence of glucose and of acetate in the growth medium, i.e., that adhA expression is subject to catabolite repression. Further analyses revealed that RamA and RamB directly bind to the adhA promoter region, that RamA is essential for the expression of adhA, and that RamB exerts a negative control on adhA expression in the presence of glucose or acetate in the growth medium. However, since the glucose-and acetate-dependent down-regulation of adhA expression was only partially released in a RamB-deficient mutant, there might be an additional regulator involved in the catabolite repression of adhA.

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“…glutamicum is able to grow on a variety of mixed carbon sources (3,44,61), which, with the exception of the sequential consumption of glucose and glutamate (25), are metabolized in parallel. It has been shown that C. glutamicum is also able to degrade a xenobiotic compound in cometabolism with readily metabolizable carbon sources (10).…”

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confidence: 99%

Cometabolism of a Nongrowth Substrate:l-Serine Utilization byCorynebacterium glutamicum

Netzer

Peters‐Wendisch

Eggeling

et al. 2004

Appl Environ Microbiol

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C-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 ␤-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 K m , 11 mM) prevents substantial L-serine degradation.Cometabolism is often observed for xenobiotic compounds which do not enable growth as a single carbon-and energy source (21). This is due, for example, to long degradation pathways and unnatural structures. On the other hand, microorganisms with a restricted metabolism, such as Lactococcus lactis, are dependent on cometabolism of essential natural compounds, e.g., amino acids (35). The amino acid L-serine is characterized by the fact that several organisms have the ability to introduce it into the central metabolism via pyruvate (35,2,16). Another distinguishing feature is its high cellular demand, exceeding the simple provision of L-serine for protein synthesis, since L-serine is additionally required for glycine, cysteine, tryptophan, and phospholipid synthesis as well as for 1-carbonunit generation (52). Glycine, in turn, is a precursor for purines and heme. In Corynebacterium glutamicum about 7.5% of the total carbon flux toward L-serine is utilized for these purposes (28). Prior estimates for Escherichia coli determined that as much as 15% of the carbon assimilated from glucose involves L-serine (42). Due to the high demand and its key position in the precursor supply, L-serine has to be regarded as an intermediate of the central metabolism (52).In spite of the presence of L-serine dehydratase (L-SerDH) (47) and the key position of L-serine, growth of E. coli on L-serine as a carbon source is very poor, allowing doubling times of about 60 h only (63). When the organism is additionally exposed to low concentrations of glycine, isoleucine, and threonine, growth is enhanced (36). Interestingly, during growth on tryptone broth, where a number of amino acids are present, L-serine is utilized immediately and earlier than any other amino acid (43). Taken together, L-serine is clearly a poor growth substrate for E. coli and is preferably cometabolized. Klebsiella aerogenes and ...

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Batch kinetics of Corynebacterium glutamicum during growth on various carbon substrates: use of substrate mixtures to localise metabolic bottlenecks

Cited by 49 publications

References 8 publications

Arabitol Metabolism of Corynebacterium glutamicum and Its Regulation by AtlR

Arabitol Metabolism of Corynebacterium glutamicum and Its Regulation by AtlR

The Alcohol Dehydrogenase Gene adhA in Corynebacterium glutamicum Is Subject to Carbon Catabolite Repression

Cometabolism of a Nongrowth Substrate:l-Serine Utilization byCorynebacterium glutamicum

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