Mycoplasma can change DNA supercoiling by expressing gyrase, which would allow less compact regions to be transcribed more readily than tightly packed regions.
Mycoplasma can use many smaller plasmids instead of one large circular chromosome. This would allow for more transcription because the regions of DNA are shorter and require fewer transcription factors for initiation.
Mycoplasma can induce DNA supercoiling by expressing DNA helicase, which would allow tightly packed regions to be transcribed more readily.
Mycoplasma can use linear chromosomes rather than circular ones, making transcription easier because DNA is less condensed.