Translation initiation - PROKARYOTE

[drobgyn32]

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2017 Dat destoryer #175

True: Methionine, NOT N-formylmethionine is the aa used in Eukaryotes for protein synthesis initiation.

^I understand this, but do not understand the statement below:

True: in prokaryotes, the protein synthesis initiation step places the initiator codon of mRNA, usually AUG and f-Met-tRNA at the proper site on the ribosome.

^How is this true? We just learned that prokaryotes do NOT use AUG methionine.

 

[DAT Destroyer]

2017 Dat destoryer #175

True: Methionine, NOT N-formylmethionine is the aa used in Eukaryotes for protein synthesis initiation.

^I understand this, but do not understand the statement below:

True: in prokaryotes, the protein synthesis initiation step places the initiator codon of mRNA, usually AUG and f-Met-tRNA at the proper site on the ribosome.

How is this true? We just learned that prokaryotes do NOT use AUG methionine.

The most common start codon is AUG. However, in prokaryotes there may be some, UUG, GUG, AUU and CUG. However, they are not seen very often.