RT Journal Article SR Electronic(1) A1 Diep, Dzung B. A1 Axelsson, Lars A1 Grefsli, Camilla A1 Nes, Ingolf F. YR 2000 T1 The synthesis of the bacteriocin sakacin A is a temperature-sensitive process regulated by a pheromone peptide through a three-component regulatory system JF Microbiology, VO 146 IS 9 SP 2155 OP 2160 DO https://doi.org/10.1099/00221287-146-9-2155 PB Microbiology Society, SN 1465-2080, AB Sakacin A is a bacteriocin produced by Lactobacillus sakei Lb706. The gene cluster (sap) encompasses a regulatory unit composed of three consecutive genes, orf4 and sapKR. sapKR encode a histidine protein kinase and a response regulator, while orf4 encodes the putative precursor of a 23-amino-acid cationic peptide (termed Sap-Ph). The authors show that Sap-Ph serves as a pheromone regulating bacteriocin production. Lb706 produced bacteriocin when the growth temperature was kept at 25 or 30 °C, but production was reduced or absent at higher temperatures (33·5–35 °C). Production was restored by lowering the growth temperature to 30 °C, but at temperatures of 33–34 °C also by adding exogenous Sap-Ph to the growth medium. A knock-out mutation in orf4 abolished sakacin A production. Exogenously added Sap-Ph complemented this mutation, unambiguously showing the essential role of this peptide for bacteriocin production. Another sakacin A producer, Lactobacillus curvatus LTH1174, had a similar response to temperature and exogenously added Sap-Ph., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-146-9-2155