Supercoil Levels in and Chromosomes Are Regulated by the C-Terminal 35⁻38 Amino Acids of GyrA.

Prokaryotes have an essential gene-gyrase-that catalyzes negative supercoiling of plasmid and chromosomal DNA. Negative supercoils influence DNA replication, transcription, homologous recombination, site-specific recombination, genetic transposition and sister chromosome segregation. Although and Typhimurium are close relatives with a conserved set of essential genes, DNA has a supercoil density 15% higher than , and cannot grow at the supercoil density maintained by wild type (WT) .