Rapid communication: notes on biofilm porosity

Abstract

Microbiology is approaching a critical intellectual challenge, which is brought into focus by the discovery of viable but nonculturable organisms in nature. In a continuous operational sequence, beginning with Louis Pasteur one and a half centuries ago, we have been preoccupied by the planktonic bacterial cells that grow so rapidly and readily in our cunningly formulated media in vitro. Until very recently a bacterial cell was not considered to exist, if it could not make the very rapid transition from its phenotype in its natural environment to this stylized entity in the test tube. Modern direct observations of natural populations have shown hundreds of morphotypes of bacterial cells that yield no corresponding planktonic cells on culture, and even more modern nucleotide analyses have shown the presence of many organisms that have never yielded culturable cells. Microbiology is seen to have concentrated on the minority of bacteria that can be cultured from nature, partly because of our understandable preoccupation with organisms that cause specific problems such as acute diseases of ourselves or of our domestic plants and animals. For these special organisms we have always developed suitable media and culture methods, and many of these media and methods actually discourage the growth of “environmental†species. This approach has produced the vaccines and antibiotics that still control many bacterial diseases, but the science of microbiology has committed a grave intellectual error, and we know very little of the neglected organisms that didn’t happen to like to grow in our specialized media.