Microbial Biofilms

Abstract

Direct observations have clearly shown that biofilm bacteria predominate, numerically and metabolically, in virtually all nutrient-sufficient ecosystems. Therefore, these sessile organisms predominate in most of the environmental, industrial, and medical problems and processes of interest to microbiologists. If biofilm bacteria were simply planktonic cells that had adhered to a surface, this revelation would be unimportant, but they are demonstrably and profoundly different. We first noted that biofilm cells are at least 500 times more resistant to antibacterial agents. Now we have discovered that adhesion triggers the expression of a sigma factor that derepresses a large number of genes so that biofilm cells are clearly phenotypically distinct from their planktonic counterparts. Each biofilm bacterium lives in a customized microniche in a complex microbial community that has primitive homeostasis, a primitive circulatory system, and metabolic cooperativity, and each of these sessile cells reacts to its special environment so that it differs fundamentally from a planktonic cell of the same species.

Lipid and polymer nanoparticles for drug delivery to bacterial biofilms

“…[6] Upon adhesion, the bacterial cells start producing extracellular matrix and group together in densely packed bacterial clusters. From the mature biofilm, individual cells or biofilm fragments are released and can colonize new surfaces ( Figure 1).…”

Role of biofilm in catheter-associated urinary tract infection☆

“…12 Survival advantages conferred by the biofilm community include resistance to being swept away by simple shear forces, resistance to phagocytosis, and resistance to antimicrobial agents. 1,2 For example, in a rabbit model of CAUTI, 400 mg/kg of amdinocillin was required to eliminate Escherichia coli from the surface of the urinary catheter, although the minimum inhibitory concentration of amdinocillin against this organism in the planktonic state was 0.5 μg/mL. 13 Because several studies show that antibiotics can penetrate mature biofilms thoroughly, [14][15][16] the slow growth rates of organisms in biofilms is probably the major factor in conferring resistance.…”

Biopelícula extrarradicular: reporte de un caso clínico

“…Por otra parte, estas infecciones son difícil-mente resueltas por el sistema inmune del hospedero; incluso, dicha respuesta es capaz de ocasionar daños en los tejidos en vecindad a las biopelículas [20][21][22][23][24][25][26][27].…”

“…En estas situaciones clínicas, la cirugía apical representa una manera eficaz y efectiva de desorganizar o eliminar a los microorganismos contenidos en estas organizaciones microbianas [14][15][16][17][18][19][20][21][22][23][24][25][26][27].…”