BIOL 150 Lecture Notes - Lecture 8: Rifampicin, Antimicrobial Resistance, Gram Staining
Document Summary
Replicate dna and undergo binary fission or cytokinesis. Oldest fossils of bacteria, 3. 5 billion years old. First fossils of eukaryotes 1. 8 billion years old. 5000 species named but millions probably exist - very high taxonomic diversity. Humans alone host ~1000 different species of bacteria. Humans are walking, talking habitats of bacteria and archaea. 1 tsp of soil may contain billions of microbial cells. Drop of sewater = 10k to 100k cells per ml. Oxygen-free mud, hot springs, 10000 m below sea level, antartic sea, near submarine volcanoes. Idvididual w aids and tb treated w antibiotics 2x wkly rifampin and isonizaid 1/2 a yr. Rifampin binds tightly to the rna of tb, few daughter cells produces in presence of drug. Examples of extreme environments where some bacteria or archaea live. May provide insights to the origin of life. A dyeing system, gram staining, distinguishes 2 general types. Plasma membrane surrounded by simple cell wall w extensive peptidoglycan (gram-positive)
