Essential <i>Bacillus</i> <i>subtilis</i> genes

TLDR

Identification of unknown and unexpected essential genes opens research avenues to better understanding of processes that sustain bacterial life. The study estimates the minimal gene set required to sustain bacterial life in nutritious conditions by systematically inactivating Bacillus subtilis genes. The authors systematically inactivated Bacillus subtilis genes to determine the minimal gene set needed for life in nutrient‑rich conditions. Of ~4,100 genes, 192 are indispensable, 79 predicted essential, most essential genes cluster in core metabolic domains, are widely conserved across Bacteria, Archaea, and Eukarya, yet genes for cell envelope, shape, division, respiration, and glycolysis are frequently lost or essential, and only 4% encode unknown functions.

Abstract

To estimate the minimal gene set required to sustain bacterial life in nutritious conditions, we carried out a systematic inactivation of Bacillus subtilis genes. Among ≈4,100 genes of the organism, only 192 were shown to be indispensable by this or previous work. Another 79 genes were predicted to be essential. The vast majority of essential genes were categorized in relatively few domains of cell metabolism, with about half involved in information processing, one-fifth involved in the synthesis of cell envelope and the determination of cell shape and division, and one-tenth related to cell energetics. Only 4% of essential genes encode unknown functions. Most essential genes are present throughout a wide range of Bacteria, and almost 70% can also be found in Archaea and Eucarya. However, essential genes related to cell envelope, shape, division, and respiration tend to be lost from bacteria with small genomes. Unexpectedly, most genes involved in the Embden–Meyerhof–Parnas pathway are essential. Identification of unknown and unexpected essential genes opens research avenues to better understanding of processes that sustain bacterial life.