Guanhua Xuan, Shichao Xuan, Luying Xun
Hydrogen sulfide has been proposed as a signaling molecule; however, the convincing examples were rarely reported. It has been reported that H2S is first oxidized to sulfane sulfur that then induces sulfur-metabolizing genes in several bacteria. Recently, the findings that sulfane sulfur rather than H2S activate MexR-regulated antibiotic resistance and LasR-mediated quorum sensing are direct examples that sulfane sulfur act as signaling molecules regulating bacterial physiology beyond sulfur-metabolism. Since the intracellular level of sulfane sulfur is always associated with growth phases, sulfane sulfur is likely the common signaling molecules in bacteria. This mini review focuses on the key findings on sulfane sulfur signaling in bacteria.