Biomaterial Database

Protective effect of elongation factor 2 on the inactivation of ribosomes by the toxic lectins abrin and ricin. 1976

C Fernandez-Puentes, and S Benson, and S Olsnes, and A Pihl

The inactivation of rabbit reticulocyte ribosomes by abrin and ricin A-chains was studied by incubating ribosomes with the A-chains and testing, after various periods of time, aliquots of the ribosomes for their ability to polymerize phenylalanine. The presence of elongation factor 2 (EF-2) reduced the rate of inactivation of ribosomes by the A-chains. The protective effect of EF-2 was strongly enhanced by GTP and, to a lesser extent, also by GDP or dGTP. Other nucleotides had no demonstrable effect. Much less protection was found after binding of Phe-tRNA to ribosomes in the presence of EF-1 (enzymic binding) or in the presence of high Mg2+ concentration (non-enzymic binding). The data indicate that when EF-2 binds to the ribosomes it completely or partially covers the target site for abrin and ricin A-chains. The possibility that EF-1 also binds to this site is discussed.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D010441	Peptide Chain Elongation, Translational	A process of GENETIC TRANSLATION, when an amino acid is transferred from its cognate TRANSFER RNA to the lengthening chain of PEPTIDES.	Chain Elongation, Peptide, Translational,Protein Biosynthesis Elongation,Protein Chain Elongation, Translational,Protein Translation Elongation,Translation Elongation, Genetic,Translation Elongation, Protein,Translational Elongation, Protein,Translational Peptide Chain Elongation,Biosynthesis Elongation, Protein,Elongation, Genetic Translation,Elongation, Protein Biosynthesis,Elongation, Protein Translation,Elongation, Protein Translational,Genetic Translation Elongation,Protein Translational Elongation
D010445	Peptide Elongation Factors	Protein factors uniquely required during the elongation phase of protein synthesis.	Elongation Factor,Elongation Factors, Peptide,Factor, Elongation,Factors, Peptide Elongation
D010940	Plant Proteins	Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which PLANT PROTEINS, DIETARY is available.	Plant Protein,Protein, Plant,Proteins, Plant
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D012156	Reticulocytes	Immature ERYTHROCYTES. In humans, these are ERYTHROID CELLS that have just undergone extrusion of their CELL NUCLEUS. They still contain some organelles that gradually decrease in number as the cells mature. RIBOSOMES are last to disappear. Certain staining techniques cause components of the ribosomes to precipitate into characteristic "reticulum" (not the same as the ENDOPLASMIC RETICULUM), hence the name reticulocytes.	Reticulocyte
D006150	Guanine Nucleotides		Guanine Nucleotide,Guanosine Phosphates,Nucleotide, Guanine,Nucleotides, Guanine,Phosphates, Guanosine
D006160	Guanosine Triphosphate	Guanosine 5'-(tetrahydrogen triphosphate). A guanine nucleotide containing three phosphate groups esterified to the sugar moiety.	GTP,Triphosphate, Guanosine
D000036	Abrin	A toxic lectin from the seeds of jequirity, Abrus precatorius L. Very active poison. Five different proteins have so far been isolated: Abrus agglutinin, the component responsible for: hemagglutinating activity, & abrins a-d, the toxic principals each consisting of two peptide chains are held together by disulfide bonds.	Abrin A,Abrin C
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia