Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

70S initiation complex

Oxazolidinones are a new class of synthetic antimicrobial agents, which have activity against many important pathogens, including methicillin-resistant Staphylococcus aureus and others. Oxazolidinones (e.g. linezolid or eperezolid) inhibit bacterial protein synthesis by inhibiting the formation of the 70S initiation complex by binding to the 50S ribosomal subunit close to the interface with the 3OS subunit. [Pg.919]

In the following section, we describe protocols for tests aimed at screening for compounds capable of interfering with some of the main activities of this factor, such as (a) recognition and binding of initiator tRNA (b) codon-dependent ribosomal binding of fMet-tRNA leading to the formation of a 30S or 70S initiation complex (c) ribosome-dependent hydrolysis of GTP and (d) accommodation of fMet-tRNA in the ribosomal P-site and formation of the first peptide bond (initiation dipeptide formation). [Pg.290]

Binds to a site on the bacterial 23S ribosomal RNA of the SOS subunit and prevents the formation of a functional 70S initiation complex, which is an essential component of the bacterial translation process. [Pg.55]

I GTP is cleaved and initiation I factors are released when the 50S subunit arrives to form the 70S initiation complex. [Pg.438]

The large (50S) ribosomal subunit now binds, with the release of IF1 and IF2 and hydrolysis of GTP, to form a 70S initiation complex. [Pg.223]

Initiation in prokaryotes involves binding of mRNA by small ribosomal subunit (30S), followed by association of the fMet-tRNAmet (initiator formyl-methionyl-tRNAmel) that recognizes the initiation codon. Large ribosomal subunit (50S) then joins to form the 70S initiation complex. In eukaryotes, the initiator aminoacyl-tRNA is not formylated. Instead Met-tRNAf161 forms 40S preinitiation complex with small ribosomal subunit (40S) in the absence of mRNA. The association of mRNA results in a 40S preinitiation complex, which forms an 80S initiation complex after large ribosomal subunit (60S) joins. [Pg.150]

Subsequent to the formation of the 70S initiation complex in bacteria, at what steps of translation is energy consumed in the form of high-energy phosphate bonds ... [Pg.518]

Formylmethionyl-tRNAf Is Placed in the P Site of the Ribosome During Formation of the 70S Initiation Complex... [Pg.1229]

When the 70S initiation complex has been formed, the ribosome is ready for the elongation phase of protein synthesis. The fMet-tRNAf molecule occupies the P site on the ribosome. The other two sites for tRNA molecules, the A site and the E site, are empty. Formylmethionyl-tRNAf is positioned so that its anticodon pairs with the initiating AUG (or GUG) codon on mRNA. This interaction sets the reading frame for the translation of the entire mRNA. [Pg.1229]

Figure 29.27. Translation Initiation in Prokaryotes. Initiation factors aid the assembly first of the 308 initiation complex and then of the 70S initiation complex. Figure 29.27. Translation Initiation in Prokaryotes. Initiation factors aid the assembly first of the 308 initiation complex and then of the 70S initiation complex.
Early steps in protein synthesis in prokaryotes formation of the 30S preinitiation complex and 70S initiation complex. [Pg.577]

Protein synthesis takes place m three phases initiation, elongation, and termination. In prokaryotes, mRNA, formylmethionyl-tRNAf (the special initiator tRNA that recognizes AUG), and a 30S riboso-mal subunit come together with the assistance of initiation factors to form a 30S initiation complex. A SOS ribosomal subunit then joins this complex to form a 70S initiation complex, in which fMet-tRNAf occupies the P site of the ribosome. [Pg.887]

ACTIVE FIGURE 12.10 The formation of an initiation complex. The 30S ribosomal subunit binds to mRNA and fmet-tRNA in the presence of GTP and the three initiation factors, IF-1, IF-2, and IF-3, forming the 30S initiation complex. The 50S ribosomal subunit is added, forming the 70S initiation complex. Sign in at www.thomsonedu.com/iogin to expiore an interactive version of this figure. [Pg.342]

Eist the components of the 70S initiation complex and indicate the roles of the initiation factors (IF) and GTP in its formation. [Pg.519]

S initiation complex IF-3 is released and the joining of 508 to the 30S initiation complex is accompanied by the IF-2 mediated GTP hydrolysis, which results in the release of IF-1 and IF-2 and the formation of the 70S initiation complex. Initiation results in the formation of the 70S initiation complex, IMet-tRNAf mRNA ribo-some complex in which the fMet-tRNAf " occupies the P-site while the A-site is poised to accept an incoming aa-tRNA. [Pg.476]

Diagrammatic representation of translation on prokaryotic ribosomes. The elongation cycle starts by interaction of the 70S initiation complex with fMet- tRNA EFTu GTP. In all subsequent rounds of the cycle, fMet-tRNArEFT tGTP interacts with the mRNA ribosome complex carrying the growing polypeptide chain. Termination occurs when n amino acids have been incorporated, where n represents the number of codons between the initiation codon AUG and the termination codon (in this example UAA). [Pg.560]

After dissociation of the three initiation factors, the 70S initiation complex is ready to bind a ternary complex consisting of aminoacyl-tRNA, elongation factor EF-Xu and GXP. This complex binds to the ribosomal acceptor-site, the A-site, in such a way that the anticodon of the tRNA is in close contact with the complementary codon on the... [Pg.331]

FIGURE 5 Translation initiation. In prokaryotes, three initiation factors are responsible for assembling the initiation complex prior to decoding of a message. The mRNA and initiator tRNA bind to the small ribosomal subunit in random order, with IF2 selectively binding initiator tRNA. Hydrolysis of IF2-bound GTP promotes formation of the SOS initiation complex. Initiation Factors 1 and 3 leave the complex, and the large ribosomal subunit binds to form the 70S initiation complex with release of IF2. [Pg.186]

The association of ribosomal subunits produces two distinguishable sites (called P for peptidyl-tRNA binding site and A for aminoacyl-tRNA binding site) which function in the addition of amino acids to the formylmethionyl residue. According to the current two-site model (Figure 17.8), the 70S initiation complex contains an occupied site P. The appropriate ternary complex, con-... [Pg.216]


See other pages where 70S initiation complex is mentioned: [Pg.285]    [Pg.1057]    [Pg.1058]    [Pg.219]    [Pg.504]    [Pg.1229]    [Pg.577]    [Pg.876]    [Pg.876]    [Pg.1057]    [Pg.1058]    [Pg.341]    [Pg.343]    [Pg.1649]    [Pg.523]    [Pg.277]    [Pg.204]    [Pg.315]    [Pg.316]    [Pg.331]    [Pg.100]    [Pg.186]    [Pg.188]   
See also in sourсe #XX -- [ Pg.876 , Pg.876 ]




SEARCH



Complex initiating

Initiation complex

© 2024 chempedia.info