Choosing the Right Lifestyle: Regulation of Developmental Pathways by Cyclic Di-GMP

Abstract

This chapter provides an understanding of the general developmental concepts associated with cyclic di-GMP (c-di-GMP) regulation. It also provides a broad understanding of the concepts of planktonic and biofilm lifestyles and the modes utilized by bacteria to achieve directed movement. There are distinct advantages to both free-swimming and biofilm lifestyles. In general, free-swimming bacteria may be better suited to identifying new environments, permitting colonization, and proliferation. The authors discuss the two lifestyles by defining the regulatory principles associated with c-di-GMP important for the transition between these lifestyles. They then discuss the biofilm lifestyle and the transition to this lifestyle from a planktonic state. A central concept of c-di-GMP regulation is that its accumulation favors biofilm formation and inhibits motility and the planktonic lifestyle. Importantly, the ability to utilize one or more of the modes of movement can dictate the efficiency of the transition from the planktonic to biofilm lifestyle. Furthermore, it is not only the expression of these systems that is being controlled by c-di-GMP. Another exciting area of exploration is identifying the environmental signals that control c-di-GMP signaling. The fascinating flexibility of c-di-GMP has the net result of a versatile signaling molecule that can induce a gradual response, through changes in gene expression, as well as an immediate response by directly altering the functionality of macromolecular assembly pathways.