Reduced folate supply as a key to enhanced L-serine production by Corynebacterium glutamicum.

The amino acid L-serine is required for pharmaceutical purposes, and the availability of a sugar-based microbial process for its production is desirable. However, a number of intracellular utilization routes prevent overproduction of L-serine, with the essential serine hydroxymethyltransferase (SHMT) (glyA) probably occupying a key position. We found that constructs of Corynebacterium glutamicum strains where chromosomal glyA expression is dependent on Ptac and lacIQ are unstable, acquiring mutations in lacIQ, for instance.

[Streptococcal infection, acute kidney failure and interstitial nephritis].

The relationship between streptococcal infection and renal disease has been object of multiple studies. Streptococcal infection may induce acute glomerulonephritis or interstitial nephritis. We report a patient with a streptococcal infection who developed acute renal failure.

Monitoring and control of industrial downstream processing of sugar beet molasses.

In present work the determination of several amino acids during the industrial chromatographic desugarisation of molasses is presented. The use of innovative biosensor systems for highly specific detection of serine is described. Using two-dimensional fluorescence spectrometry, a non-invasive method for the determination of several product fractions could be established in an industrial chromatographic procedure.

From sugar beet molasses to Lyphan. Integrated quality management from the raw material to the drug.

L-tryptophan is produced at the AMINO GmbH (Frellstedt, FRG) via biocatalytical condensation of the amino acid L-serine with indole. As a biocatalyst, tryptophan synthetase is used which is produced in high activities by a natural mutant Escherichia coli strain. The enzyme mechanism and specificity and the individual process-parameters for the biotransformation procedure are explained as well as the purification process of educts and products.

Flow injection analysis system for the supervision of industrial chromatographic downstream processing in biotechnology.

Sugar beet molasses is a natural resource for various products used in daily life, ranging from sucrose to amino acids for pharmaceutical industry. The separation of molasses into these high value components is performed on a large scale by ion exchange/exclusion chromatography. A biosensor system was set up for the "in time" analysis of serine and sucrose during molasses desugarisation.