by Roberto — The se­cre­tion of small mol­e­cules is likely one of the most com­mon ways in which bac­te­ria in­ter­act with other bac­te­ria, re­gard­less of their en­vi­ron­men­tal set­ting. Like many oth­ers, I like to re­fer to that uni­verse of chem­i­cal in­ter­ac­tions as "bac­te­r­ial chem­i­cal ecol­ogy."