Organization and nucleotide sequence of the glutamine synthetase (glnA) gene from Lactobacillus delbrueckii subsp. bulgaricus

Y. Ishino, P. Morgenthaler, H. Hottinger, D. Soll

Research output: Contribution to journalComment/debatepeer-review

9 Citations (Scopus)


A 3.3-kb BamHI fragment of Lactobacillus delbrueckii subsp. bulgaricus DNA was cloned and sequenced. It complements an Escherichia coli glnA deletion strain and hybridizes strongly to a DNA containing the Bacillus subtilis glnA gene. DNA sequence analysis of the L. delbrueckii subsp. bulgaricus DNA showed it to contain the glnA gene encoding class I glutamine synthetase, as judged by extensive homology with other prokaryotic glnA genes. The sequence suggests that the enzyme encoded in this gene is not controlled by adenylylation. Based on a comparison of glutamine synthetase sequences, L. delbrueckii subsp. bulgaricus is much closer to gram-positive eubacteria, especially Clostridium acetobutylicum, than to gram-negative eubacteria and archaebacteria. The fragment contains another open reading frame encoding a protein of unknown function consisting of 306 amino acids (ORF306), which is also present upstream of glnA of Bacillus cereus. In B. cereus, a repressor gene, glnR, is found between the open reading frame and glnA. Two proteins encoded by the L. delbrueckii subsp. bulgaricus gene were identified by the maxicell method; the sizes of these proteins are consistent with those of the open reading frames of ORF306 and glnA. The lack of a glnR gene in the L. delbrueckii subsp. bulgaricus DNA in this position may indicate a gene rearrangement or a different mechanism of glnA gene expression.

Original languageEnglish
Pages (from-to)3165-3169
Number of pages5
JournalApplied and environmental microbiology
Issue number9
Publication statusPublished - 1992
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Food Science
  • Applied Microbiology and Biotechnology
  • Ecology


Dive into the research topics of 'Organization and nucleotide sequence of the glutamine synthetase (glnA) gene from Lactobacillus delbrueckii subsp. bulgaricus'. Together they form a unique fingerprint.

Cite this