Your question is very general. ABC transporters are ubiquitous in mycoplasmas. Some of the transporters are importers required for nutrient uptake and others are exporters. Because of the mycoplasma's limited ability to synthesize many essential molecules de novo, they must import them. With no such transporters, the mycoplasma would be dead and hence not pathogenic. Some mycoplasmas produce one or more toxins that are probably secreted by ABC exporters. An exporter in Mycoplasma pulmonis is required for capsular polysaccharide production. Most of the ABC transporters in mycoplasmas are identified through bioinformatics. The molecules they transport and their specific role in pathogenesis remains to be determined.