Biotechnological production of L-tryptophan

An isolated or synthetic enzyme having the sequence of one of SEQ ID NO:

• 2, SEQ ID NO:
• 4, SEQ ID NO:
• 5, and SEQ ID NO:
• 30.

A method for the biotechnological production of L-tryptophan, comprising the steps of

• a) growing a genetically modified Escherichia coli cell, the cell being genetically modified to express an indole-3-glycerol phosphate synthase, IGPs, the IGPs being less sensitive to inhibition by anthranilate compared to the wild type IGPs of the bacterial cell, wherein the IGPs has
• alanine or glycine at position 60 instead of serine, or
• valine at position 8 instead of isoleucine, or
• phenylalanine at position 188 instead of leucine, or
• glutamine at position 58 instead of serine, valine at position 59 instead of proline, phenylalanine at position 60 instead of serine and glutamine at position 61 instead of lysine,
• compared to the sequence of SEQ ID NO:
• 1, in a suitable growth medium in a bioreactor, and separating L-tryptophan from the growth medium, or
• b) growing an Escherichia coli cell being genetically modified to express a heterologous enzyme having IGPs activity, the enzyme being less sensitive to inhibition by anthranilate compared to the wild type IGPs of the Escherichia coli cell, in a suitable growth medium in a bioreactor, and separating L-tryptophan from the growth medium, or
• c) using an enzyme having the sequence of one of SEQ ID NO:
• 2, SEQ ID NO:
• 3, SEQ ID NO:
• 4, SEQ ID NO:
• 5, or SEQ ID NO:
• 30, in biosynthesis of L-tryptophan in a suitable medium, and separating L-tryptophan from the medium.