The present disclosure provides a Bacillus subtilis strain, a recombinant B. subtilis strain and use thereof, belongs to the technical field of microbial fermentation. B. subtilis strain RF1-6 provided by the present disclosure is a mutant strain with the highest riboflavin yield screened by gene modification and mutagenesis using a high riboflavin-producing strain RF1 as a starting strain, deposited at China Center for Type Culture Collection (CCTCC) under accession number M 2022565. Riboflavin yield can be increased by 22.8% compared with that of the high riboflavin-producing strain RF1.

The present disclosure provides a Bacillus subtilis strain, a recombinant B. subtilis strain and use thereof, belongs to the technical field of microbial fermentation. B. subtilis strain RF1-6 provided by the present disclosure is a mutant strain with the highest riboflavin yield screened by gene modification and mutagenesis using a high riboflavin-producing strain RF1 as a starting strain, deposited at China Center for Type Culture Collection (CCTCC) under accession number M 2022565. Riboflavin yield can be increased by 22.8% compared with that of the high riboflavin-producing strain RF1.

The present invention to the identification of a novel isolated bacterial strain, the Limosilactobacillus reuteri strain which is characterized by a naturally occurring overproduction of riboflavin (vitamin B2) compared to other known strains of lactobacilli. Said strain of the Limosilactobacillus species is deposited under accession number LMG P-32020. In a further aspect, also the uses of said L. reuteri strain are disclosed herein. In particular, the use of said strain in food and feed industry, human and veterinary health, large-scale vitamin production, cosmetics and consumer care products is disclosed.

The present invention to the identification of a novel isolated bacterial strain, the Limosilactobacillus reuteri strain which is characterized by a naturally occurring overproduction of riboflavin (vitamin B2) compared to other known strains of lactobacilli. Said strain of the Limosilactobacillus species is deposited under accession number LMG P-32020. In a further aspect, also the uses of said L. reuteri strain are disclosed herein. In particular, the use of said strain in food and feed industry, human and veterinary health, large-scale vitamin production, cosmetics and consumer care products is disclosed.

Microorganisms and bioprocesses are provided that convert gaseous C1 containing substrates, such as syngas, producer gas, and renewable H.sub.2 combined with CO.sub.2, into nutritional and other useful bioproducts.

The present invention provides an improved biotechnological production of riboflavin (also referred herein as vitamin B2) through modification in the operon containing the riboflavin biosynthetic genes (rib operon), in particular modifications of/in the leader sequences (rib leader) upstream of the corresponding riboflavin biosynthetic genes (rib operon). Furthermore, the present invention relates to genetically engineered microorganisms carrying said modified sequences, processes to generate said modified sequences/microorganisms and the use thereof for production of riboflavin.

The present invention provides an improved biotechnological production of riboflavin (also referred herein as vitamin B2) through modification in the operon containing the riboflavin biosynthetic genes (rib operon), in particular modifications of/in the leader sequences (rib leader) upstream of the corresponding riboflavin biosynthetic genes (rib operon). Furthermore, the present invention relates to genetically engineered microorganisms carrying said modified sequences, processes to generate said modified sequences/microorganisms and the use thereof for production of riboflavin.

The present invention relates to a method for producing highly-concentrated L-amino acid and riboflavin simultaneously, and a microorganism for simultaneously producing L-amino acid and riboflavin. Specifically, the present invention relates to a modified microorganism for producing L-lysine or L-threonine, and riboflavin simultaneously, wherein the microorganism belonging to Corynebacterium sp. capable of producing L-lysine or L-threonine is modified by enhancing the activity of an enzyme family expressed by a rib operon which contains riboflavin biosynthesis gene family. Also, the present invention relates to a method for the simultaneous production of L-lysine or L-threonine, and riboflavin using the modified microorganism, and relates to a formulation or granular formulation, feed, and feed additive, containing L-lysine or L-threonine, and riboflavin produced from a culture medium of the modified microorganism.

The present invention relates to a method for producing highly-concentrated L-amino acid and riboflavin simultaneously, and a microorganism for simultaneously producing L-amino acid and riboflavin. Specifically, the present invention relates to a modified microorganism for producing L-lysine or L-threonine, and riboflavin simultaneously, wherein the microorganism belonging to Corynebacterium sp. capable of producing L-lysine or L-threonine is modified by enhancing the activity of an enzyme family expressed by a rib operon which contains riboflavin biosynthesis gene family. Also, the present invention relates to a method for the simultaneous production of L-lysine or L-threonine, and riboflavin using the modified microorganism, and relates to a formulation or granular formulation, feed, and feed additive, containing L-lysine or L-threonine, and riboflavin produced from a culture medium of the modified microorganism.

Microorganisms and bioprocesses are provided that convert gaseous C1 containing substrates, such as syngas, producer gas, and renewable H.sub.2 combined with CO.sub.2, into nutritional and other useful bioproducts.