Chapter 1 : Bacillus subtilis: From Cells to Genes and from Genes to Cells

Abstract:

A fairly detailed outline of Bacillus subtilis physiology and the identification of genes for metabolic and developmental pathways were available by the late 1970s. The invention of recombinant DNA technology set the stage for the second great leap forward in our understanding of B. subtilis organism. With the whole B. subtilis genome sequence in hand, one can design microarray assays of gene transcription in which all genes can be analyzed simultaneously. Comparisons of gene function, organization, and regulation in diverse bacteria have revealed that the proteins of macromolecular synthesis and the enzymes of biosynthesis and degradation are remarkably well conserved throughout the prokaryotic world. It is equally striking, however, how differently gram-positive and gram-negative bacteria regulate gene expression and the activities of their gene products. The study of B. subtilis, in both the pregenomic and the postgenomic eras, has reinforced our sense that this multitalented organism has evolved mechanisms of synthesis and regulation that are novel, subtle, and interesting. The integrated (and presumably defective) phages have added their genes to the genome, increasing the cell's genetic capability by horizontal gene transmission. Great leaps forward in our understanding of the natural world are obviously dependent on major advances in technology. But the value of a technical advance resides in its ability to facilitate and stimulate intellectual leaps. The future of the field will depend on our ability to sift through the abundance of new data generated by genome sequencing and its dependent technologies, and extract patterns and rules.