MICRB265 Lecture Notes - Lecture 4: Crystal Violet, Safranin, Last Universal Common Ancestor
4 Nov 2017
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Document Summary
Bacteria were first life forms, and the foundation of biology. Vast majority of microbes do not cause diseases. Only anaerobic metabolism for first 2 billion years. Submarine mounds may have been prebiotic incubators for cellular life. Geochemistry can support abiotic production of amino acids, lipids, sugars and nucleotides. Hydrothermal mineral water + cool oxidized ocean water = precipitate mound. Mineral structures may have produced energy-rich compartments. Reasonably sure that life began in rna world, where rna was catalytic and self-replicating and may have catalyzed its own synthesis. Earliest viruses may have evolved from rna genome cell-like structures. Earliest cells = dna, rna, protein, and membrane system for every conservation. Last universal common ancestor (luca) existed 3. 8-3. 7 billion years ago, then . Early earth was anoxic therefore primitive cells utilized anaerobic metabolism for energy production. Evolved ability to use n2 (nitrogen fixation) Chemolithotrophic metabolism produced lots of organic compounds.
