Likewise, phosphorylation is a common PTM mechanism, that is involved in the central metabolic processes and in the regulation of the efflux-pump NorA, by acting on the MgrA protein; however, the role of phosphorylation in staphylococcal pathogenesis, as well as the role of other PTMs, needs to be further investigated, especially regarding AD (Ohlsen and Donat, 2010). This evidence concerns the gene MAS1 and Alzheimer disease.