The acetic acid bacterium (AAB)Gluconobacter oxydansincompletely oxidizes a wide variety of carbohydrates and is therefore used industrially for oxidative biotransformations. ForG. oxydans, no system was available that allows regulatable plasmid-based expression. We found that thel-arabinose-inducible P(BAD)promoter and the transcriptional regulator AraC fromEscherichia coliMC4100 performed very well inG. oxydans. The respective pBBR1-based plasmids showed very low basal expression of the reporters beta-glucuronidase and mNeonGreen, up to 480-fold induction with 1%l-arabinose, and tunability from 0.1 to 1%l-arabinose. InG. oxydans621H,l-arabinose was oxidized by the membrane-bound glucose dehydrogenase, which is absent in the multi-deletion strain BP.6. Nevertheless, AraC-P(BAD)performed similar in both strains in the exponential phase, indicating that a gene knockout is not required for application of AraC-P(BAD)in wild-typeG. oxydansstrains. However, the oxidation product arabinonic acid strongly contributed to the acidification of the growth medium in 621H cultures during the stationary phase, which resulted in drastically decreased reporter activities in 621H (pH 3.3) but not in BP.6 cultures (pH 4.4). These activities could be strongly increased quickly solely by incubating stationary cells ind-mannitol-free medium adjusted to pH 6, indicating that the reporters were hardly degraded yet rather became inactive. In a pH-controlled bioreactor, these reporter activities remained high in the stationary phase (pH 6). Finally, we created a multiple cloning vector witharaC-P(BAD)based on pBBR1MCS-5. Together, we demonstrated superior functionality and good tunability of an AraC-P(BAD)system inG. oxydansthat could possibly also be used in other AAB.