BIO 3124 Lecture Notes - Lecture 12: Escherichia Coli, Insertion Sequence, Streptomycin
6 Jan 2015
School
Department
Course
Professor
Document Summary
Lecture 12: bacterial genetics - chromosome and genetic elements. Even eukaryotic microorganisms have a bigger genome than the upper limits of bacteria. There is a lower limit to having a small genome size. Both bacteria and archaea have a similar lower limit (0. 6 and 0. 5 mbp) E. coli (4. 5 mbp) is quite self-sufficient (e. g. : don"t need to supply extra growth factors) and is not dependent on a living host for survival. Any organism that is not dependent on host cell must be atleast 1 mbp. Free living organism genomes are at least 1 mbp. The smallest genomes are usually from obligate symbiont or obligate intracellular pathogens. They lack many genes encoding for biosynthesis enzymes. The genome includes the main dna along with associated proteins and rna. Prokaryotic genomes are generaly haploid (single copy of the chromosomes) The typical chromosome is circular (i. e. : nucleoid) This was first observed using pulse field gel electrophoresis.
