12/9

1. DNA adheres to cell membrane
2. DNA pulled through secretin pore           by retraction of T4P protein
3. 1/2 of DNA helix moves into
    cytoplasm/the other is degraded
4. The new strand H bonds to
     homologous sequence/old strand
     degraded

    Chromosomal        DNA Replication​

         2. transduction

            Any other DNA...???
                    Plasmids!

  Bacteria rely on the FtsZ protein   which forms a membrane bound ring   during binary fission. FtsZ is akin to 
 tubulin which is found in the   eukaryotic mitotic microtubules.

  Microbial Genetics

             VERY cool!
​ More on this next week...:)

    12/11

         1. transformation
             
         2. transduction
             
​          3. conjugation

  binary fission = vertical gene transfer

Stayed tuned to explore how plasmid recombination is used to produce valuable molecules for therapeutic use and research....

                                   Plasmids are...
1. mostly seen as circular molecules of DNA (but
    may be linear and/or RNA)
2. singular or many copies per cell (># of copies
    amplifies characteristics of plasmid genes) 
3. may carry only a few to many hundreds of genes  
4. found in more than half of all bacteria
5. also found in eukaryotes (ex: some yeast)
6. specific plasmids may be found only in closely
     related bacteria (F-plasmid and enteric bacteria)
     while others (P/Pseudomonas) are found in
     dozens of different species of bacteria and are
     associated with ABX resistance

         3. conjugation

         1. transformation

            vertical and horizontal! Whoa

E coli exhibits a single 4.6 Mb circular chromosome.  Human cells exhibit 3000 Mb arranged in 23 pairs of linear chromosomes.

 Binary Fission...and then there where two

 Plasmids are considered part of the
 mobilome or MGEs = mobile genetic elements.   MGEs are associated with antimicrobial   resistance gene transfer among different   bacterial species

E. coli cells will divide about every 20               minutes at 37 degrees C...
     that makes a billion (bajillion!)    bacteria from one bacterium in only                                  ten hours!

There are exceptions to the single circular chromosome...
Gram-positive Borrelia and Streptomyces exhibit linear chromosomes Gram-negative tumefaciens (agro) exhibits one linear AND one circular chromosome.