The invention relates to an isolated polynucleotide containing a polynucleotide sequence selected from the group a) polynucleotide that is at least 70% identical with a polynucleotide that codes for a polypeptide containing the amino acid sequence of SEQ ID No. 2, b) polynucleotide that codes for a polypeptide containing an amino acid sequence that is at least 70% identical with the amino acid sequence of SEQ ID No. 2, c) polynucleotide that is complementary to the polynucleotides of a) or b), and d) polynucleotide containing at least 15 consecutive nucleotides of the polynucleotide sequence of a), b) or c), and to a process for the production of L-amino acids by fermentation using coryneform bacteria in which at least the citE gene is present in attenuated form, and to the use of polynucleotides containing the sequences of the invention as hybridization probes.