Host-derived amino acids support the proliferation of symbiotic bacteria

摘要: Animals are typically colonized by diverse bacterial symbionts, many of which commensal and, in numerous cases, even essential for their host’s proper development and growth. In exchange, the host must supply a sufficient array quantity nutrients to support proliferation persistence its microbial community. this investigation, we have examined such nutritional environment determining symbiotic competence auxotrophic mutants bioluminescent bacterium Vibrio fischeri, demonstrated that squid Euprymna scolopes provides at least 9 aa growing culture V. fischeri present light-emitting organ. We also collected analyzed extracellular fluid from organ, symbionts reside, confirmed it contained significant amounts amino acids. The combined results suggested host-derived free acids, as well peptides or proteins, source acids growth symbionts. This work describes technique sample surrounding without contamination tissue components combination with molecular genetic studies, allows characterization conditions cooperative animal–bacterial symbiosis.