Difference between revisions of "Part:BBa K1927002"

 
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===Usage and Biology===
 
===Usage and Biology===
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During the last decade antibiotic resistance has grown not only in incidents but also in
  
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awareness among the public. Rapid detection of these incidents is essential in the battle
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against sophisticated bacteria. Beta lactamases are enzymes that provides one of the many
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mechanisms of antibiotic resistance. Its for this reason regulary used among researchers as
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a selection marker. Bacteria that has been subjected to a procedure where foreign DNA is
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introduced, an antibiotic resistance gene is often use to check if colonies succsesfully has
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taken up the DNA and expressed it.
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An example of this is ampicillin which is a highly used selection marker. The need for a
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selection marker in genetical engineering has been shown extremly usefull. By transforming
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a bacteria with a particular gene plus an antibiotic resistance gene it allows the researcher to
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know exactly which colonies that has taken up the DNA. By plating them out on agar plates
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with a given antibiotic, only the bacteria with the resistance gene can grow. Cells that did not
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manage to take up the DNA will die.
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The mechanism of beta lactamases are oriented to the bacterial cell wall. This cell wall is
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unique to bacteria and consist of several components. Gram Positive and gram negative
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bacteria will have a different cell wall composition.
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In general, Gram-positive bacteria have a thicker layer of cell wall as well as a layer of
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cytoplasmic membrane. These layers consist of several conserved compounds such as
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monomeric disaccharide tetrapeptide, which are usually also those that will trigger an
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immunological defence respons of the host.
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Gram-negative bacteria (e.g., Escherichia coli) typically contain an outer membrane, an
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intervening periplasmic space where a thin layer of cell wall resides, and a layer of
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cytoplasmic membrane.
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Beta lactamases are usually produced both by gram negative and positive bacteria, either
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from plasmid or chromosomally. Beta lactamases are able to resist several types of
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antibiotics. These antibiotics all have in common a 4 - atom ring called beta lactam ring
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which the enzyme are able to hydrolyze and break open and the molecule looses its
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antibacterial function.
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Penicillin, a regulary used antibiotic have such a beta lactam ring.
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This drug was the first antibiotic to be discovered and is still widely used today. This ring will
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bind to an enzyme (DD –transpeptidase) that is in charge of renewing the bacterial cell wall.
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Without this enzyme there will be no new formations of peptidoglycans for the cell wall and
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the integrity of the bacterial cell wall will be lost, it will eventually rupture and the bacteria will
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die. By hydrolyzing the ring, it will make the molecule unable to bind to the cell wall
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producing enzyme, thus the Penicillin have lost its destructive activity.
 
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<span class='h3bb'>Sequence and Features</span>
 
<span class='h3bb'>Sequence and Features</span>

Revision as of 08:00, 14 October 2016


β lactamase AmpR

This gene conveys resistance to a common antibiotic called Ampicillin. In research it is often used as a selection marker

Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    INCOMPATIBLE WITH RFC[1000]
    Illegal BsaI site found at 716