Algae, Tree, Herbs, Bush, Shrub, Grasses, Vines, Fern, Moss, Spermatophyta, Bryophyta, Fern Ally, Flower, Photosynthesis, Eukaryote, Prokaryote, carbohydrate, vitamins, amino acids, botany, lipids, proteins, cell, cell wall, biotechnology, metabolities, enzymes, agriculture, horticulture, agronomy, bryology, plaleobotany, phytochemistry, enthnobotany, anatomy, ecology, plant breeding, ecology, genetics, chlorophyll, chloroplast, gymnosperms, sporophytes, spores, seed, pollination, pollen, agriculture, horticulture, taxanomy, fungi, molecular biology, biochemistry, bioinfomatics, microbiology, fertilizers, insecticides, pesticides, herbicides, plant growth regulators, medicinal plants, herbal medicines, chemistry, cytogenetics, bryology, ethnobotany, plant pathology, methodolgy, research institutes, scientific journals, companies, farmer, scientists, plant nutrition
Select Language:
 
   
 
 
Can't find? Try Deep Search with ePlantScience.com  
 
Share |
 
   
Main Menu
If navigation gets difficult, please click the main subject or sitemap to get the list of sub-categories
 
 
 
 
 
Related websites
 
 
 
 
 
 
 
 
Section: Genetics » Expression of Gene » Translation in Prokaryotes and Eukaryotes
 
 
If you like this page, please click:  
 
 
  Formation of amino-acyl tRNA
 
     
 
Content
⇒ Expression of Gene : Protein Synthesis 4. Translation in Prokaryotes and Eukaryotes
⇒ Formation of amino-acyl tRNA
⇒ Initiation of polypeptide 
⇒ Initiation in prokaryotes
⇒ Initiation in eukaryotes
⇒ Kozak's scanning hypothesis
⇒ Elongation of polypeptide
⇒ Binding of AA-tRNA at site 'A' of ribosome
⇒ Formation of peptide bond
⇒ Translocation of peptidyl tRNA from 'A' to 'P' site
⇒ Termination of polypeptide
⇒ Modification, folding and transport of released polypeptide
⇒ Translation in chloroplasts and mitochondria
Formation of Aminoacyl tRNA
Activation of amino acid
This reaction is brought about by the binding of an amino acid with ATP. The step is mediated by specific activating enzymes known as amino acyl RNA synthetases (amino acid is abbreviated as AA). As a result of this reaction between amino acid and adenosine triphosphate, mediated by specific enzyme, a complex (amino acyl-AMP-enzyme complex) is formed. It should be realized that amino acyl-RNA synthetases are specific with respect to amino acids. Therefore, for different amino acids, different enzymes would be required. Moreover a particular enzyme has a double specificity in so far as it can recognize its own amino acid on the one hand and its own tRNA on the other hand. This later specificity allows the second step outlined in the next section.

The transfer of amino acid to tRNA
The amino acyl-AMP-enzyme complex, formed during the step outlined above, reacts with a particular tRNA and transfers the amino acid to the tRNA. This reaction is accompanied with the liberation of AMP and the enzyme. It should be noticed in this reaction that with AA1; Enz1 and tRNA1, 1 is used as suffix to emphasize the specificity, which exists between them. A particular amino acid would require a particular enzyme and a particular species of tRNA. This would mean that for 20 amino acids, atleast 20 different enzymes and also atleast 20 different tRNA species would be required (while there are cases where more than one kind of tRNA may be available for the same amino acid, no cases are known, where the same tRNA can recognize two or more different amino acids).
 
     






     
     
 
 
     
 
Copyrights 2009 © ePlantScience.com