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The cytoplasm also contains Plasmids. Plasmids are small circular pieces of DNA that are separate from the genome and are capable of autonomous replication. Several different plasmids can be within the cytoplasm of a single bacteria. Plasmids
The cytoplasm also contains Plasmids. Plasmids are small circular pieces of DNA that are separate from the genome and are capable of autonomous replication. Several different plasmids can be within the cytoplasm of a single bacteria. Plasmids
can be transferred between bacteria during binary fission or through a process called conjugation. Plasmid DNA codes for characteristics including antibiotic resistance and endotoxin production.<br />
can be transferred between bacteria during binary fission or through a process called conjugation. Plasmid DNA codes for characteristics including antibiotic resistance and endotoxin production.<br />
==Flagella & Pili/Fimbrae==
Motile bacteria have flagella allowing them to move into suitable micro-environments in response to physical or chemical stimuli. It is mainly gram negative bacteria that possess flagella and they are rarely present in cocci species. Flagella are normally several times longer than the bacterial cell and are composed of the protein flagellin. Flagella are usually anchored
to the cell wall.<br />
Pili are straight, hair-like appendages composed of pilin and also anchored to the cell wall. Pili are most common on gram negative
bacteria. In pathogenic bacteria pili function as adhesions for receptors on mammalian cells. <br />
==Endospores==
Endospores are dormant bodies that are highly resistant to the environment. The only genera of pathogenic bacteria that are able to
produce endospores are Bacillus and Clostridium. Endospores have a “spore coat” and are effectively in a dehydrated state with negligible metabolic activity. Due to the thermostability of endospores they can only be destroyed with certainty by moist heat at 121C for 15 mins.<br />
An endospore will reactivate in response to environmental factors such as exposure to heat, abrasion of the spore coat or environmental acidity. Reactivation occurs in three stages; activation, initiation and outgrowth. In the correct conditions, germination will occur in which the spore coat is degraded and water is absorbed.
[[Category:Bacteria]]
[[Category:Bacteria]]