MICR 221 Lecture Notes - Lecture 14: Autolysin, Gram-Negative Bacteria, Deoxyribonuclease
1 Jan 2016
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In tranformation, because adding naked pieces of dna, dna-ase will chew it up. Unlike conjugation and transduction where dna is always protected. Dna bound by dna binding protein (comea), one strand degraded by nuclease (n). Comec forms channel to get dna across the cm. Dna taken in by membrane vesicleschance of dna incorporation much higher because it will only bind dna from close relatives (vs streptococcus that binds everything but only incorporates dna from close relatives) **almost universal method for cells not transformable by other methods. Generalized transduction any gene since packaging is random. Converted his- to a his+, as dna is incorporated the transducing particle never gives rise to new phages because it has no phage dnahomologous recombination resulting in an altered genotype from dna it picked from the phage. Just bacterial dna so won"t direct synthesis of phage synthesis. Can treat lysogens with uv light which will cause the excision of the prophage and go into lytic cycle.
