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From Proteopedia
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== Introduction == | == Introduction == | ||
| - | The tetanus toxin is produced by the bacteria ''Clostridium tetani''. Clostridium bacteria produces distinct neurotoxins that are extremely potent to humans. Both ''Clostridium botulinum'' and ''Clostridium tetani'' form the clostridial neurotoxin family. This family is classified as part of the peptidase M27 family of proteins, which are metalloproteases. Metalloproteases bind with a divalent cation, usually zinc, which activates water molecules within the active site to hydrolyze peptide bonds. | + | The tetanus toxin is produced by the bacteria ''Clostridium tetani''. Clostridium bacteria produces distinct neurotoxins that are extremely potent to humans. Both ''Clostridium botulinum'' and ''Clostridium tetani'' form the clostridial neurotoxin family [Krishnamurthy et al., 2005]. This family is classified as part of the peptidase M27 family of proteins, which are metalloproteases. Metalloproteases bind with a divalent cation, usually zinc, which activates water molecules within the active site to hydrolyze peptide bonds [PDB]. |
| - | The tetanus toxin effects the central nervous system by inhibiting the release of neurotransmitters, glycine and gamma-aminobutyric acid, into the synaptic cleft of the spinal cord. This causes spastic paralysis, or tetanus. | + | The tetanus toxin effects the central nervous system by inhibiting the release of neurotransmitters, glycine and gamma-aminobutyric acid, into the synaptic cleft of the spinal cord. This causes spastic paralysis, or tetanus [Krishnamurthy et al., 2005]. |
The toxin is produced after the bacterial cell's active, exponential growth phase. | The toxin is produced after the bacterial cell's active, exponential growth phase. | ||
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== Structure == | == Structure == | ||
<Structure load='1YVG' size='500' frame='true' align='right' caption='Insert caption here' scene='Insert optional scene name here' /> | <Structure load='1YVG' size='500' frame='true' align='right' caption='Insert caption here' scene='Insert optional scene name here' /> | ||
| - | The precursor polypeptide of the tetanus toxin is cleaved during post-translational modification into a heavy and light chains. These two chains remain linked by a disulfide bridge. The heavy chain is the C-terminal end of the protein and the light chain is the N-terminal end of the protein. If the two chains are separated, the toxin becomes non-toxic. | + | The precursor polypeptide of the tetanus toxin is cleaved during post-translational modification into a heavy and light chains. These two chains remain linked by a disulfide bridge. The heavy chain is the C-terminal end of the protein and the light chain is the N-terminal end of the protein. If the two chains are separated, the toxin becomes non-toxic [PDB]. |
| - | Tetanus toxin has three functional domains: binding, translocation, and catalytic. The heavy chain is responsible for binding the toxin to the specific neural receptors and translocating the catalytic light chain domain into the neural cytosol. The light chain is the zinc-binding domain containing a zinc-binding motif. This metalloprotease activity causes toxicity. | + | Tetanus toxin has three functional domains: binding, translocation, and catalytic. The heavy chain is responsible for binding the toxin to the specific neural receptors and translocating the catalytic light chain domain into the neural cytosol. The light chain is the zinc-binding domain containing a zinc-binding motif. This metalloprotease activity causes toxicity [Krishnamurthy et al., 2005]. |
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== Mechanism of Action == | == Mechanism of Action == | ||
| - | Tetanus toxin binds to the neural cells through gangliosides and a second protein receptor. Once bound, they enter the cytosol via a vesicle membrane. Here, they attack and cleave the proteins that forms the synaptic vesicle fusion apparatus. | + | Tetanus toxin binds to the neural cells through gangliosides and a second protein receptor. Once bound, they enter the cytosol via a vesicle membrane. Here, they attack and cleave the proteins that forms the synaptic vesicle fusion apparatus [Krishnamurthy et al., 2005]. |
Revision as of 17:28, 1 May 2012
Contents |
TETANUS TOXIN
| This Sandbox is Reserved from 13/03/2012, through 01/06/2012 for use in the course "Proteins and Molecular Mechanisms" taught by Robert B. Rose at the North Carolina State University, Raleigh, NC USA. This reservation includes Sandbox Reserved 451 through Sandbox Reserved 500. | ||||||
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More help: Help:Editing For more help, look at this link: http://www.proteopedia.org/wiki/index.php/Help:Getting_Started_in_Proteopedia IntroductionThe tetanus toxin is produced by the bacteria Clostridium tetani. Clostridium bacteria produces distinct neurotoxins that are extremely potent to humans. Both Clostridium botulinum and Clostridium tetani form the clostridial neurotoxin family [Krishnamurthy et al., 2005]. This family is classified as part of the peptidase M27 family of proteins, which are metalloproteases. Metalloproteases bind with a divalent cation, usually zinc, which activates water molecules within the active site to hydrolyze peptide bonds [PDB]. The tetanus toxin effects the central nervous system by inhibiting the release of neurotransmitters, glycine and gamma-aminobutyric acid, into the synaptic cleft of the spinal cord. This causes spastic paralysis, or tetanus [Krishnamurthy et al., 2005]. The toxin is produced after the bacterial cell's active, exponential growth phase.
Structure
The precursor polypeptide of the tetanus toxin is cleaved during post-translational modification into a heavy and light chains. These two chains remain linked by a disulfide bridge. The heavy chain is the C-terminal end of the protein and the light chain is the N-terminal end of the protein. If the two chains are separated, the toxin becomes non-toxic [PDB]. Tetanus toxin has three functional domains: binding, translocation, and catalytic. The heavy chain is responsible for binding the toxin to the specific neural receptors and translocating the catalytic light chain domain into the neural cytosol. The light chain is the zinc-binding domain containing a zinc-binding motif. This metalloprotease activity causes toxicity [Krishnamurthy et al., 2005].
Mechanism of ActionTetanus toxin binds to the neural cells through gangliosides and a second protein receptor. Once bound, they enter the cytosol via a vesicle membrane. Here, they attack and cleave the proteins that forms the synaptic vesicle fusion apparatus [Krishnamurthy et al., 2005].
Medical Implications or Possible ApplicationsTetanus toxin is still a main concern to public health taking several hundred lives each year. |
