MIC 4124 Lecture Notes - Lecture 4: Biofilm, Alginic Acid, Nitrogen Fixation
8 Feb 2017
School
Department
Course
Professor
Document Summary
Acyl hsl signalling is important for development of mature biofilm: density based sensing system. Cells can detach from biofilm: based on signals. No genetic changes as a cell transitions from planktonic to biofilm cell: different genes expressed instead. Slow growth means less energy output: do not consume resources and produce less waste. Provides protection from antimicrobial agents and predators: antibiotics and biocides. Provides protection from immune system for pathogens. In the environment: kitchen pipes, sink sponge, toothbrush, on teeth. Late colonizers rely on presence of earlier colonizers. Only primary colonizers have adhesins for initial layer of plaque. In medicine: catheters, cardiac tissue, p aeruginosa in sputum of cf patient. Hypothesized that surface attached cells express different genes than planktonic cells. Initial experiments used dna arrays and 2d gel analysis: 0. 5% of genes activated in biofilms while 0. 5% repressed in p aeruginosa.
