Biomaterial Database

Two separate peptides in Escherichia coli methionyl-tRNA synthetase form the anticodon binding site for methionine tRNA. 1993

H Y Kim, and H Pelka, and S Brunie, and L H Schulman

Department of Developmental Biology & Cancer, Albert Einstein College of Medicine, Bronx, New York 10461.

The amino acid residues Asn391, Arg395, and Trp461 in methionyl-tRNA synthetase (MetRS) of Escherichia coli are involved in the anticodon-dependent recognition of its cognate tRNAs [Ghosh, G., Pelka, H., & Schulman, L.H. (1990) Biochemistry 29, 2220-2225; Ghosh, G., Kim, H.Y., Demaret, J. P., Brunie, S., & Schulman, L.H. (1991) Biochemistry 30, 11767-11774]. While tryptophan at position 461 was shown to bind directly to the wobble base at position 34 in the tRNA(Met) anticodon, the role of residues 391-395 was not thoroughly explored. To gain further insight into the role of the 391-395 residues and nearby residues, appropriate mutations were analyzed for aminoacylation activity, as well as tRNA binding. Mutations of the phylogenetically conserved asparagine at position 391 increased the Km for aminoacylation of tRNA(Met) 18-40-fold. Further analysis using fluorescence titration indicated that the mutation affected initial complex formation, since the Kd for tRNA(Met) binding had increased at least 15-fold over wild type. Kinetic analysis of mutationally altered derivatives of MetRS with a series of tRNA(Met) derivatives containing base substitutions in the anticodon revealed sequence-specific interaction between the amino acid residue at position 391 and the U36 of the anticodon of tRNA(Met). In addition to position 391, position 387 was also found to affect tRNA(Met) binding and aminoacylation, indicating a possible significant role in interaction of the enzyme with the anticodon of tRNA(Met). These results indicate that the peptide segment containing residues 391-395 is involved in the direct recognition of the 3' end of the anticodon.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008718	Methionine-tRNA Ligase	An enzyme that activates methionine with its specific transfer RNA. EC 6.1.1.10.	Methionyl T RNA Synthetase,Met-tRNA Ligase,Methionyl-tRNA Synthetase,Ligase, Met-tRNA,Ligase, Methionine-tRNA,Met tRNA Ligase,Methionine tRNA Ligase,Methionyl tRNA Synthetase,Synthetase, Methionyl-tRNA
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010446	Peptide Fragments	Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.	Peptide Fragment,Fragment, Peptide,Fragments, Peptide
D010710	Phosphates	Inorganic salts of phosphoric acid.	Inorganic Phosphate,Phosphates, Inorganic,Inorganic Phosphates,Orthophosphate,Phosphate,Phosphate, Inorganic
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D000215	Acylation	The addition of an organic acid radical into a molecule.
D000255	Adenosine Triphosphate	An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.	ATP,Adenosine Triphosphate, Calcium Salt,Adenosine Triphosphate, Chromium Salt,Adenosine Triphosphate, Magnesium Salt,Adenosine Triphosphate, Manganese Salt,Adenylpyrophosphate,CaATP,CrATP,Manganese Adenosine Triphosphate,MgATP,MnATP,ATP-MgCl2,Adenosine Triphosphate, Chromium Ammonium Salt,Adenosine Triphosphate, Magnesium Chloride,Atriphos,Chromium Adenosine Triphosphate,Cr(H2O)4 ATP,Magnesium Adenosine Triphosphate,Striadyne,ATP MgCl2
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D000926	Anticodon	The sequential set of three nucleotides in TRANSFER RNA that interacts with its complement in MESSENGER RNA, the CODON, during translation in the ribosome.	Anticodons