No man's land: Species ‐specific formation of exclusion zones bordering Actinomyces graevenitzii microcolonies in nanoliter cultures

“Exclusion zone” formation aroundActinomyces graevenitzii microcolonies in microfluidic nanoliter volume co ‐culture chambers. This species‐specific phenomenon appears to relate toA.  graevenitzii colony stress and can alter inflammatory responses. AbstractTo survive within complex environmental niches, including the human host, bacteria have evolved intricate interspecies communities driven by competition for limited nutrients, cooperation via complementary metabolic proficiencies, and establishment of homeostatic relationships with the host immune system. The study of such complex, interdependent relationships is often hampered by the challenges of culturing many bacterial strains in research settings and the limited set of tools available for studying the dynamic behavior of multiple bacterial species at the microscale. Here, we utilize a microfluidic ‐based co‐culture system and time‐lapse imaging to characterize dynamic interactions betweenStreptococcus species,Staphylococcus aureus,and Actinomyces species. Co ‐culture ofStreptococcus cristatus orS. salivarius in nanoliter compartments withActinomyces graevenitzii revealed localized exclusion of Streptococcus and Staphylococcus from media immediately surroundingA. graevenitzii microcolonies. This community structure did not occur withS. mitis orS. oralis strains or in co ‐cultures containing otherActinomycetaceae species such asS. odontolyticus orA. naeslundii. Moreover, fewer neutrophils were at...
Source: MicrobiologyOpen - Category: Microbiology Authors: Tags: ORIGINAL ARTICLE Source Type: research