Epigenetics Theoretical Limits of Synthetic Genomes: The Cases of Artificials &lt;em&gt;Caulobacter &lt;/em&gt;(&lt;em&gt;C. eth-2.0), Mycoplasma Mycoides (JCVI-Syn 1.0, JCVI-Syn 3.0 and JCVI_3A), E-coli and YEAST chr XII&lt;/em&gt;