MCB 3020 Lecture Notes - Lecture 13: Virulence Factor, Lactone, Bacteriocin
Document Summary
At high intensities generates singlet oxygen (1o2) Microbial growth in natural environments: microbial environments are complex, constantly changing, often contain low nutrient concentrations (oligotrophic environment) and may expose a microorganism to overlapping gradients of nutrients and environmental factors. Biofilm formation: microbes reversibly attach to conditioned surface and release polysaccharides, proteins, and dna to form the extracellular polymeric substance (eps, additional polymers are produced as microbes reproduce and biofilm matures. Biofilm microorganisms: the eps a(cid:374)d (cid:272)ha(cid:374)ge i(cid:374) atta(cid:272)hed orga(cid:374)is(cid:373)s" physiology prote(cid:272)ts (cid:373)i(cid:272)ro(cid:271)es fro(cid:373) harmful agents. Uv light, antibiotics, antimicrobials: when formed on medical devices, such as implants, often lead to illness, sloughing off of organisms can result in contamination of water phase above the biofilm such as in a drinking water system. Quorum sensing: acylhomoserine lactone (ahl) is an autoinducer molecule produced by many gram-negative organisms. Once inside the cell, induces expression of target genes regulating a variety of functions. Quorum sensing systems: processes regulated by quorum sensing involve host-microbe interactions.
