We thank Gary Sawers for helpful discussion and for reading the manuscript, and Ronald Mertz for the sequencing primers. This work was supported by a grant from the Deutsche Forschungsgemeinschaft (SFB 145).
Nucleotide sequence and expression of an operon in Escherichia coli coding for formate hydrogenylase components
Article first published online: 27 OCT 2006
Volume 4, Issue 2, pages 231–243, February 1990
How to Cite
Böhm, R., Sauter, M. and Böck, A. (1990), Nucleotide sequence and expression of an operon in Escherichia coli coding for formate hydrogenylase components. Molecular Microbiology, 4: 231–243. doi: 10.1111/j.1365-2958.1990.tb00590.x
- Issue published online: 27 OCT 2006
- Article first published online: 27 OCT 2006
- Received 22 August, 1989; revised 25 October, 1989.
An 8kb segment of DNA from the 58/59 min region of the E. coli chromosome, which complements the defect of a mutant devoid of hydrogenase 3 activity, has been sequenced. Eight open reading frames were identified which are arranged in a transcriptional unit; all open reading frames were transcribed and translated in vivo in a T7 promoter/polymerase system. Analysis of the amino acid sequences derived from the nucleic acid sequences revealed that one of them, open reading frame 5 (0RF5), exhibits significant sequence similarity to conserved regions of the large subunit from Ni/Fe hydrogenases. Two of the open reading frames (orf2, orf6) code for proteins apparently carrying iron-sulphur clusters of the 4Fe/4S ferredoxin type. The product of one of the open reading frames, orf7, displays extensive sequence similarity with protein G from the chloroplast electron transport chain. ORF3 and ORF4, on the other hand, are extremely hydrophobic proteins with nine and six putative transmembrane helices, respectively. Over a limited hydrophilic sequence stretch, bordered by putative transmembrane areas, ORF3 and ORF4 exhibit homology with subunits 4 and 1 of mitochondrial and plastid NADH-ubiquinol oxidoreductases, respectively. The operon described, therefore, appears to comprise genes for redox carriers linking formate oxidation to proton reduction and for a hydrogenase of hitherto unique composition.