Improving P acquisition by plants and elaborating sustainable strategies for the use of P, are problems that will be solved
only by using global approaches and by collaboration of scientists from different fields. However, PSMs will be playing a
major role in solving the P problem. Although there is a debate going on the report indicating that a bacterium can use
arsenic instead of P [45], more research in this area will probably lead to the discovery of new mechanisms used by the
bacterium to grow in an environment where there is a dearth of P.