Disclosed is a modified microorganism producing putrescine or ornithine, and a method for producing putrescine or ornithine using the same.

Disclosed are transaminase mutants and use thereof. The amino acid sequence of the transaminase mutant is obtained by the mutation of the amino acid sequence as shown in SEQ ID NO: 1, and the mutation at least comprises one of the following mutation sites: the 19-th site, the 41-th site, the 43-th site, the 72-th site, the 76-th site, the 92-th site, the 107-th site, the 125-th site, the 132-th site, the 226-th site, the 292-th site, the 295-th site, the 308-th site, and the 332-th site; and the 19-th site is mutated into a serine, the 41-th site is mutated into a serine, the 43-th site is mutated into an asparagine, a glycine in the 72-th site is mutated into a leucine, etc.; or the amino acid sequence of the transaminase mutant has the mutation sites in the mutanted amino acid sequence, and has more than 80% homology to the mutanted amino acid sequence.

Disclosed is a modified microorganism producing putrescine or ornithine, and a method for producing putrescine or ornithine using the same.

Provided herein are methods, compositions, and non-naturally occurring microbial organism for preparing compounds such as 1-butanol, butyric acid, succinic acid, 1,4-butanediol, 1-pentanol, pentanoic acid, glutaric acid, 1,5-pentanediol, 1-hexanol, hexanoic acid, adipic acid, 1,6-hexanediol, 6-hydroxy hexanoic acid, -Caprolactone, 6-amino-hexanoic acid, -Caprolactam, hexamethylenediamine, linear fatty acids and linear fatty alcohols that are between 7-25 carbons long, linear alkanes and linear -alkenes that are between 6-24 carbons long, sebacic acid and dodecanedioic acid comprising: a) converting a C.sub.N aldehyde and pyruvate to a C.sub.N+3 -hydroxyketone intermediate through an aldol addition; and b) converting the C.sub.N+3 -hydroxyketone intermediate to the compounds through enzymatic steps, or a combination of enzymatic and chemical steps.

The present disclosure relates to a novel polypeptide having an ability to export an ornithine-based product, and a method for producing an ornithine-based product using the same.

Disclosed is a modified microorganism producing putrescine or ornithine, and a method for producing putrescine or ornithine using the same.

Disclosed is a modified microorganism producing putrescine or ornithine, and a method for producing putrescine or ornithine using the same.

Disclosed is a modified microorganism producing putrescine or ornithine, and a method for producing putrescine or ornithine using the same.

Genetically engineered bacteria, pharmaceutical compositions thereof, and methods of modulating and treating disorders associated with hyperammonemia are disclosed.

The present disclosure relates to a polypeptide having an acyltransferase activity or a microorganism including the same; a composition for preparing N-acetyl-L-methionine, the composition including the polypeptide or microorganism; and a method of preparing N-acetyl-L-methionine using the polypeptide or microorganism. Further, the present disclosure relates to a polynucleotide encoding the polypeptide and an expression vector including the polynucleotide. Since the microorganism including a novel acyltransferase according to the present disclosure has enhanced acyltransferase activity, this microorganism can be efficiently used for producing N-acetyl-L-methionine by acetylating L-methionine.