Open AccessMolecular cloning of an immunogenic and acid‐induced isocitrate dehydrogenase gene from Coxiella burnetii
Author(s) -
Nguyen Sa,
To Ho,
Yamaguchi Tsuyoshii,
Fukushi Hideto,
Hirai Katsuya
Publication year - 1999
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1999.tb13607.x
Subject(s) - coxiella burnetii , biology , isocitrate dehydrogenase , gene , escherichia coli , q fever , microbiology and biotechnology , molecular cloning , cloning (programming) , recombinant dna , salmonella enterica , enzyme , biochemistry , peptide sequence , programming language , computer science
The Coxiella burnetii icd gene encoding an immunogenic dimeric NADP + ‐dependent isocitrate dehydrogenase (IDH) was cloned by screening a C. burnetii genomic library with a human positive serum and sequenced. The predicted gene product consists of 427 amino acids ( M r =46 600) and showed high identity to the IDHs of Escherichia coli (74%), Salmonella enterica (73%) and IDH‐I of Vibrio sp. (71%). The cloned gene complemented an icd ‐defective E. coli mutant producing a recombinant IDH that had the same biochemical properties as the enzyme from purified C. burnetii . Unlike the homologs from other bacteria, the cloned enzyme was expressed to the highest level in low pH conditions. This distinct property of the cloned IDH suggests that C. burnetii icd gene may have a role in the adaptation of the organism to the harsh acidic environment of the eucaryotic phagolysosomes.