摘要:
The present invention relates to a method for the production of methionine using modified strains with attenuated transformation of threonine. This can be achieved by reducing threonine transformation into glycine, and/or by reducing its transformation to α-ketobutyrate. The invention also concerns the modified strains with attenuated transformation of threonine.
摘要:
The present invention claims an isolated polypeptide having L-amino-acid-N-acyl transferase enzymatic activity and a modified microorganism in which this enzyme is overexpressed. Substrates of said enzyme include mainly methionine and their derivatives or analogs. Overexpression in sulphur-containing amino acid producing microorganisms permits the production of large amounts of N-acylated sulphur-containing amino acids. The isolation of the N-acylated sulphur-containing amino acids from the fermentation medium is also claimed.
摘要:
The invention provides modification to the polynucleotide coding sequence for Pichia angusta NAD (P)H: nitrate reductase [YNaR1; GenBank accession number Z49110], which has Enzyme Commission number 1.7.1.2 (formerly EC 1.6.6.2), yielding the polynucleotide coding sequence for simplified eukaryotic nitrate reductase (S-NaR1). The invention also provides a method for recombinant expression of said polynucleotide code in the cells of the methylotrophic yeast Pichia pastoris to produce the polypeptide for S-NaR1, which binds the host-produced molybdenum-molybdopterin cofactor and intracellularly forms catalytically active, nitrate-reducing enzyme as small and stable multimeric proteins. The invention also provides a method for rapid and high-yielding purification of S-NaR1 by utilizing the hexa-histidine sequence at the carboxyl-terminus of said polypeptide for immobilized metal affinity chromatography.
摘要:
The present invention relates to a method for the production of methionine using modified strains with attenuated transformation of threonine. This can be achieved by reducing threonine transformation into glycine, and/or by reducing its transformation to α-ketobutyrate. The invention also concerns the modified strains with attenuated transformation of threonine.
摘要:
The present invention claims an isolated polypeptide having L-amino-acid-N-acyl transferase enzymatic activity and a modified microorganism in which this enzyme is overexpressed. Substrates of said enzyme include mainly methionine and their derivatives or analogs. Overexpression in sulphur-containing amino acid producing microorganisms permits the production of large amounts of N-acylated sulphur-containing amino acids. The isolation of the N-acylated sulphur-containing amino acids from the fermentation medium is also claimed.