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EF-Tu binds an aminoacylated tRNA molecule in the cytoplasm and allows entry into the ribosome <ref name="gp"/>. EF-Tu binds a cavity between the 30S and 50S ribosomal subunits, while the tRNA anticodon associates with the mRNA codon in the A site of the ribosome <ref name="gp3">PMID: 19536129 </ref>.. If the pairing is incorrect, the tRNA will likely leave the ribosome. However, if a correct pairing has occurred, EF-Tu hydrolyzes guanosine triphosphate (GTP) to the diphosphate form (GDP)<ref name="gp"/>. This hydrolysis results in a change in conformation, releasing the tRNA into the ribosome. The dissociation allows the tRNA molecule to then completely interact with the A site of the ribosome the amino acid on the tRNA can be transferred to the growing peptide chain via covalent bond formation and EF-G to act for translocation along the mRNA sequence <ref name="gp"/>. The GDP-bound EF-Tu molecule can then interact with EF-Ts, which exchanges the GDP for a new GTP and prepares EF-Tu to interact with another charged amino acid. In this way, EF-Tu is a vital component in the propcess of lengthening a peptide during protein synthesis.
EF-Tu binds an aminoacylated tRNA molecule in the cytoplasm and allows entry into the ribosome <ref name="gp"/>. EF-Tu binds a cavity between the 30S and 50S ribosomal subunits, while the tRNA anticodon associates with the mRNA codon in the A site of the ribosome <ref name="gp3">PMID: 19536129 </ref>.. If the pairing is incorrect, the tRNA will likely leave the ribosome. However, if a correct pairing has occurred, EF-Tu hydrolyzes guanosine triphosphate (GTP) to the diphosphate form (GDP)<ref name="gp"/>. This hydrolysis results in a change in conformation, releasing the tRNA into the ribosome. The dissociation allows the tRNA molecule to then completely interact with the A site of the ribosome the amino acid on the tRNA can be transferred to the growing peptide chain via covalent bond formation <ref name="gp"/>. The GDP-bound EF-Tu molecule can then interact with EF-Ts, which exchanges the GDP for a new GTP and prepares EF-Tu to interact with another charged amino acid, once EF-G has acted for translocation along the mRNA sequecne. In this way, EF-Tu is a vital component in the propcess of lengthening a peptide during protein synthesis.


EF-Tu has also been shown to play a role in the inhibition of tetracycline during protein synthesis in many different organisms <ref name="gp"/>. EF-Tu may be a target protein of tetracycline, although this idea has commonly been dismissed because the ribosome may be inhibited in the presence of the antibiotic <ref name="gp"/>. Now however, it has been demonstated that Tm-EF-Tu-MgGDP is bound in a complex during crystallization, binding the the GTPase active site. This information could be useful for developing mechanisms of counteracting resistance to this particular antibiotic <ref name="gp"/>.  
EF-Tu has also been shown to play a role in the inhibition of tetracycline during protein synthesis in many different organisms <ref name="gp"/>. EF-Tu may be a target protein of tetracycline, although this idea has commonly been dismissed because the ribosome may be inhibited in the presence of the antibiotic <ref name="gp"/>. Now however, it has been demonstated that Tm-EF-Tu-MgGDP is bound in a complex during crystallization, binding the the GTPase active site. This information could be useful for developing mechanisms of counteracting resistance to this particular antibiotic <ref name="gp"/>.  


[[Image:EF-TuCycle.jpg | frame="true" | resolution='50' | caption='EF-Tu and EF-G cycle during protein synthesis at the ribosome']]
[[Image:EF-TuCycle.jpg | frame="true" | scale='0.5' | caption='EF-Tu and EF-G cycle during protein synthesis at the ribosome']]


==References==
==References==
<references/>
<references/>

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OCA, Falon Burkitt