Purification of factor EF-P, a protein that stimulates peptide-bond synthesis with certain aminoacyl-tRNA analogues

1979 ◽  
Vol 57 (6) ◽  
pp. 749-757 ◽  
Author(s):  
Bernard R. Glick ◽  
Robert M. Green ◽  
M. Clelia Ganoza
Keyword(s):  
Escherichia Coli ◽  
Molecular Weight ◽  
Protein Biosynthesis ◽  
Bond Formation ◽  
Frictional Coefficient ◽  
Peptide Bond ◽  
Asymmetric Structure ◽  
Peptide Bond Formation ◽  
Apparent Homogeneity ◽  
Stokes Radius

Factor EF-P is a nonribosomal (soluble) protein of Escherichia coli that stimulates peptide bond synthesis when certain aminoacyl-tRNA analogues are used. The purification of this protein to apparent homogeneity is described here. EF-P has a molecular weight of about 21 000, a Stokes radius of 27 Å (1 Å = 0.1 nm), and a frictional coefficient of 1.48, suggesting an asymmetric structure. By this and a number of other criteria, EF-P is a new factor that controls peptide bond formation during protein biosynthesis.

scholarly journals Effects of Ethyl and Benzyl Analogues of Spermine on Escherichia coli Peptidyltransferase Activity, Polyamine Transport, and Cellular Growth

1999 ◽  
Vol 181 (13) ◽  
pp. 3904-3911 ◽  
Author(s):  
Panagiotis Karahalios ◽  
Ioannis Amarantos ◽  
Petros Mamos ◽  
Dionysios Papaioannou ◽  
Dimitrios L. Kalpaxis
Keyword(s):  
Escherichia Coli ◽  
Bond Formation ◽  
Peptide Bond ◽  
Inhibitory Effect ◽  
Cellular Growth ◽  
Uptake System ◽  
Peptide Bond Formation ◽  
E Coli ◽  
Polyamine Transport

ABSTRACT Various ethyl and benzyl spermine analogues, including the anticancer agentN 1,N 12-bis(ethyl)spermine, were studied for their ability to affect the growth of culturedEscherichia coli cells, to inhibit [3H]putrescine and [3H]spermine uptake into cells, and to modulate the peptidyltransferase activity (EC 2. 3. 2. 12). Relative to other cell lines, growth of E. coli was uniquely insensitive to these analogues. Nevertheless, these analogues conferred similar modulation of in vitro protein synthesis and inhibition of [3H]putrescine and [3H]spermine uptake, as is seen in other cell types. Thus, both ethyl and benzyl analogues of spermine not only promote the formation and stabilization of the initiator ribosomal ternary complex, but they also have a sparing effect on the Mg2+requirements. Also, in a complete cell-free protein-synthesizing system, these analogues at low concentrations stimulated peptide bond formation, whereas at higher concentrations, they inhibited the reaction. The ranking order for stimulation of peptide-bond formation by the analogues wasN 4,N 9-dibenzylspermine >N 4,N 9-bis(ethyl)spermine ≅ N 1-ethylspermine >N 1,N 12-bis(ethyl)spermine, whereas the order of analogue potency regarding the inhibitory effect was inverted, with inhibition constant values of 10, 3.1, 1.5, and 0.98 μM, respectively. Although the above analogues failed to interact with the putrescine-specific uptake system, they exhibited high affinity for the polyamine uptake system encoded by thepotABCD operon. Despite this fact, none of the analogues could be internalized by the polyamine transport system, and therefore they could not influence the intracellular polyamine pools and growth of E. coli cells.

scholarly journals Structural Basis of CTP-Dependent Peptide Bond Formation in Coenzyme A Biosynthesis Catalyzed by Escherichia coli PPC Synthetase

Structure ◽  
2004 ◽  
Vol 12 (11) ◽  
pp. 1977-1988 ◽  
Author(s):  
Susanne Stanitzek ◽  
Martin A. Augustin ◽  
Robert Huber ◽  
Thomas Kupke ◽  
Stefan Steinbacher
Keyword(s):  
Escherichia Coli ◽  
Coenzyme A ◽  
Bond Formation ◽  
Peptide Bond ◽  
Structural Basis ◽  
Peptide Bond Formation ◽  
Coenzyme A Biosynthesis
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