Prokaryotic initiation factor-2 is a prokaryotic initiation factor.

IF2 binds to an initiator tRNA

N-Formylmethionine

N-Formylmethionine is a proteinogenic amino acid found in Bacteria and related Prokaryotic organelles. It is a derivative of the amino acid methionine in which a formyl group has been added to the amino group...

 and controls the entry of that tRNA into the ribosome. IF2, bound to GTP, binds to the 30S

30S

30S is the smaller subunit of the 70S ribosome of prokaryotes. It is a complex of ribosomal RNA and ribonucleoproteins that functions in mRNA translation...

 P site. After associating with the 30S subunit, fMet-tRNA_f binds to the IF2 then IF2 transfers the tRNA into the partial P site. When the 50S subunit joins, it hydrolyzes

Hydrolysis

Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...

 GTP

Guanosine triphosphate

Guanosine-5'-triphosphate is a purine nucleoside triphosphate. It can act as a substrate for the synthesis of RNA during the transcription process...

 to GDP

Guanosine diphosphate

Guanosine diphosphate, abbreviated GDP, is a nucleoside diphosphate. It is an ester of pyrophosphoric acid with the nucleoside guanosine. GDP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase guanine....

 and P_i

Phosphate

A phosphate, an inorganic chemical, is a salt of phosphoric acid. In organic chemistry, a phosphate, or organophosphate, is an ester of phosphoric acid. Organic phosphates are important in biochemistry and biogeochemistry or ecology. Inorganic phosphates are mined to obtain phosphorus for use in...

, causing a conformational change in the IF2 that causes IF2 to release and allow the 70S subunit to form.