 Pectobacterium atrocepticum uses three different chemoreceptors to detect 19 amino acids, including eight non-proteinogenic ones. These receptors are able to distinguish between different types of amino acids, such as branched chain amino acids, BCAA, and quaternary ammoniums. One of these receptors, PacB, is unique in its ability to detect BCAA, while the other two receptors, PacA and PacC, are similar to those found in E. This article was authored by Felix Vellando, Miguel A. Matilla, Igor B. Julin, and others.