Transfer of Genetic Information Between Different Genera

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Conjugation in a nutshell

Cell Wall basics

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The outer surfaces of a cell is generally classified as the Cell Wall. In bacteria, cell walls typically fall into 1 of two categories, Gram positive and Gram negative. The name comes from a test to determine cell
wall type in which the different cell walls pick up different
stains. Although the difference between a Gram
negative and positive may seem small, it has significant influence 
on how the bacteria survives, what the bacteria can tolerate, 
and many other influences.

Part I

Peptidoglycan is a substance possessed by both Gram positive and Gram negative bacteria. It is a structure composed of carbohydrates, proteins, and teichoic acids, which combine to form a dense lattice structure. 

White bars are carbohydrates, Red bars are peptide bonds, 
and blue bars are teichoic acids

Part II

Gram positive bacteria include bacteria such as Staphylococcus, Streptococcus, Lactobacillus, & others. These bacteria are able to survive dessication (drying out)  to an extent which allows them to survive on table tops, bathroom floors, and even in the air.
Gram positive bacteria differ from gram negative in that they posses a plasma membrane surrounded only by peptidoglycan. It is the thick, dense peptidoglycan layer that affords the gram positive bacteria relatively more protection then its gram negative counterpart. 

Part III

Gram negative bacteria include E. coli, Serratia, & others. Generally these bacteria can only exist in moist environments. They differ from Gram positive bacteria in that they possess a reduced peptidoglycan layer, but they do possess an outer membrane, which does serve as some protection for the bacterial cell, as it protects in other ways, (i.e. possessing a negative charge to drive away anything with a positive charge {electrostatic defense})