Collection of bacteria, too small to be readily discernible to the naked eye that exist as discrete structures due to limitations on bacterial movement.
Those limitations can be either intrinsically or extrinsically imposed, e.g., such as one sees during biofilm formation or in the course of bacterial growth within agar-containing media. Contrast both with free-floating (planktonic) individual bacteria, macroscopic bacterial colonies, and cellular arrangements. The latter especially can display stronger ties between individual bacteria than those seen within microcolonies, particular that result from a failure of daughter cell separation following division.
Bacterial lawns, as they mature, come to consist of a confluence of microcolonies. Phage plaque formation, as a consequence, occurs within the context of infection of microcolony-associated bacteria along with lysis of those bacteria.
To at least some degree the retention of turbidity within phage plaques, such as seen with bull's eye plaques, can be a retention of microcolonies that remain intact to varying degrees. The can occur either because the microcolony bacteria are completely resistant to the plaque-associated phages or instead because bacterial lawns mature to stationary phase prior to complete microcolony eradication by phages.
For more on especially the theory of phage-microcolony interactions, see Abedon (2011) and Abedon (2012).
For more on this topic, see Wikipedia, Google, and PubMed. Contact web master. Return to terms.