Lonza Inc.

Hans Kulla

Pavel Lehky

Armand Squaratti

Stephane Mischler

Selective detection of microorganisms is achieved by a screening technique in which radioactively labeled, low-molecular-weight metabolites produced by microorganisms to be detected reach an adsorption medium through a semipermeable medium which passes the labeled metabolites but blocks the labeled incubation medium. The adsorption medium is then subject to analysis, such as antoradiography, to detect the presence of the labeled metabolites. An analytical assembly for such detection includes a filter membrane support for growing microorganisms in discrete colonies and for holding a radioactively labeled incubating medium applied thereon, a semipermeable filter medium covering the support having the grown microorganisms and the incubating medium for passing low-molecular-weight, labeled metabolites produced by microorganisms of interest while blocking the incubating medium, and a cohesive layer of an adsorption medium conformably disposed with the filter membrane support and the semipermeable medium and being capable of adsorbing the labeled metabolites which have traversed the semipermeable medium during incubation of the assembly. Following incubation of the assembly, the adsorption medium layer is transferable for analysis, e.g., by autoradiography, to detect the presence of labeled metabolites produced by microorganisms of interest and to identify specific colonies of the microorganisms producing the radioactively labeled metabolite.

Device and method for the detection of microorganisms which produce

Selective detection of microorganisms is achieved by a screening technique in which radioactively labeled, low-molecular-weight metabolites produced by microorganisms to be detected reach an adsorption medium through a semipermeable medium which passes the labeled metabolites but blocks the labeled incubation medium. The adsorption medium is then subject to analysis, such as autoradiography, to detect the presence of the labeled metabolites. An analytical assembly for such detection includes a filter membrane support for growing microorganisms in discrete colonies and for holding a radioactively labeled incubating medium applied thereon, a semipermeable filter medium covering the support having the grown microorganisms and the incubating medium for passing low-molecular-weight, labeled metabolites produced by microorganisms of interest while blocking the incubating medium, and a cohesive layer of an adsorption medium conformably disposed with the filter membrane support and the semipermeable medium and being capable of adsorbing the labeled metabolites which have traversed the semipermeable medium during incubation of the assembly. Following incubation of the assembly, the adsorption medium layer is transferable for analysis, e.g., by autoradiography, to detect the presence of labeled metabolites produced by microorganisms of interest and to identify specific colonies of the microorganisms producing the radioactively labeled metabolite.

Process for the production of L-carnitine utilizing a microorganism. The microorganism is cultivated with crotonobetaine and/or .gamma.-butyrobetaine in the presence of a growth substrate. The enriched L-carnitine is isolated. The microorganisms used are those which are capable of producing L-carnitine while not catabolizing it from crotonobetaine and/or .gamma.-butyrobetaine. The microorganisms can be obtained by the following selection method. Microorganisms which grow with betaine, .gamma.-butyrobetaine, crotonobetaine and L-carnitine as the C- and N-source are mutated in the conventional manner. From the culture obtained by cultivating of the mutated microorganisms, those microorganisms are selected which are stable, do not catabolize L-carnitine and do not grow on L-carnitine, crotonobetaine and .gamma.-butyrobetaine, but grow with betaine.

Microorganisms useful in the process for the production of l-carnitine

Process for the production of 6-hydroxynicotinic acid from nicotinic acid. The hydroxylation is carried out enzymatically in the presence of a microorganism of the species Pseudomonas, Bacillus or Achromobacter, for example, Achromobacter xylosoxydans. Preferably the enzymatic hydroxylation is carried out at 20.degree. to 40.degree. C. and a pH of 5.5 to 9.0 under aerobic conditions. Also, preferably a 0.1 percent by weight solution up to a saturated (preferably a 0.5 to 10 percent by weight) nicotine acid solution is used.

Process for the production of 6-hydroxynicotinic acid

Process for the production of 6-hydroxynicotinic acid by biotechnological methods. Nicotinic acid is enzymatically hydroxylated in the presence of equivalent quantities of magnesium or barium ions with the help of nicotinic acid-hydroxylating microorganisms. The resultant magnesium or barium salt of the 6-hydroxynicotinic acid is separated from the reaction mixture. Then the 6-hydroxynicotinic acid is freed from the separated salts. Examples of the microorganism are the species Pseudomonas, Bacillus or Achromobacter, for example, Achromobacter xylosoxydans. Preferably the enzymatic hydroxylation is carried out at 20.degree. to 40.degree. C. and a pH of 5.5 to 9.0 under aerobic conditions.

Method for the production of 6-hydroxynicotinic acid

Process for the continuous production of L-carnitine by the microbiological method. A microorganism of the strain DSM No. 3225 (HK 1331b) type is cultivated in a bioreactor with crotonobetaine and/or .gamma.-butyrobetaine in the presence of a growth substrate. The culture fluid passes outside of the bioreactor in a circulation in which a separation of the cell is carried out. A quantity of cell-free solution, which is as large as the amount fed to the bioreactor as a substrate, is withdrawn from the bioreactor. The L-carnitine is separated from the cell-free solution.

Growing community of inventors

Visp, Switzerland

Hans Kulla