The complete norX/nxrX sequence of five Nitrobacter strains was determined showing that the norAXB/nxrAXB gene cluster is present in all hitherto described Nitrobacter species. Evidence is provided that the previously published sequence of norX in N. hamburgensis X14T contains an invalid base “insertion,” which resulted in a frameshift and a misidentified start codon.
Vanparys, B., Bodelier, P. L. E., & De Vos, P. (2006). Validation of the correct start codon of norX/nxrX and universality of the norAXB/nxrAXB gene cluster in Nitrobacter species. Current Microbiology, 53(3), 255-257. https://doi.org/10.1007/s00284-006-0161-z