EC Number   |
General Information |
Reference |
|---|
   2.3.2.12 | more |
the ribosome is capable of polymerizing at a similar rate at least 20 different kinds of amino acids from aminoacyl-tRNA carriers while using just one catalytic site, the peptidyl-transferase center (PTC). The PTC uses an induced-fit mechanism, analysis of published ribosome structures supports the hypothesis that the induced fit eliminates unreactive rotamers predominantly populated for some A-site aminoacyl esters before induction. The hypothesis is fully consistent with the wealth of kinetic data obtained with these substrates. Induction constrains the amino acids into a reactive conformation in a side-chain independent manner. The rationale of the PTC structural organization confers to the ribosome the very unusual ability to handle large as well as small substrates. An induced fit (or conformational change) is identified in the peptidyl-transferase center (PTC) of the ribosome, in which the binding of the 3' acceptor arm of an A-site aminoacyl tRNA triggers a major rearrangement of two ribosome residues, U2506 and U2585, modeling, overview. The room available inside the PTC cavity and its flexibility in the uninduced state leave some conformational freedom to the esterified amino acids. The induced fit orients the aminoacyl ester for nucleophilic attack. PTC structure-function relationship, detailed overview |
760119 |
| 2.3.2.12 | physiological function |
changes of 23S rRNA nucleotides in the 2585 region of the peptidyl transferase center, G2583A and U2584C, reduce maximum induction of tna operon expression by tryptophan in vivo without affecting the concentration of tryptophan necessary to obtain 50% induction. The growth rate of strains with ribosomes with either of these changes is not altered appreciably. In vitro analyses show that tryptophan is not as efficient in protecting TnaC-tRNAPro from puromycin action as wild-type ribosomes. However, added tryptophan does prevent sparsomycin action as it normally does with wild-type ribosomes. These two mutational changes act by reducing the ability of ribosome-bound tryptophan to inhibit peptidyl transferase activity rather than by reducing the ability of the ribosome to bind tryptophan |
698614 |
| 2.3.2.12 | physiological function |
recombinant Mycobacterium bovis strain BCG overexpressing a L,D-transpeptidase that is nutrient starved elicits a stronger Th1 type response against virulent MMycobacterium tuberculosis and is at least as protective as parent Mycobacterium bovis strain BCG |
-, 720812 |
| 2.3.2.12 | physiological function |
some of the indigenous posttranscriptional modifications of rRNA can be viewed as intrinsic antibiotic resistance mechanisms. The lack of pseudouridine at position 2504 of 23S rRNA significantly increases the susceptibility of Escherichia coli to peptidyl transferase inhibitors |
699543 |
| 2.3.2.12 | physiological function |
the enzyme catalyzes the formation of 3 -> 3 peptidoglycan cross-links of the cell wall and facilitates resistance against classical beta-lactams |
-, 736552 |
| 2.3.2.12 | physiological function |
the enzyme LdtMt5 is necessary for properly maintaining cell wall integrity |
-, 736488 |
| 2.3.2.12 | physiological function |
the LdtMt2 protein is required for virulence and resistance to amoxicillin |
-, 720522 |
