Cloning of the Glutamyl-tRNA Synthetase (gltX) Gene from Pseudomonas aeruginosa

ABSTRACT The glutamyl-tRNA synthetase (gltX) gene fromPseudomonas aeruginosa was identified. A plasmid containing a 2.3-kb insert complemented the temperature-sensitive gltXmutation of Escherichia coli JP1449, and GltX activity was demonstrated. The inferred amino acid sequence of this gene showed 50.6% identity with GltX from Rhizobium meliloti.

Download Full-text

Nucleotide and deduced amino acid sequence of human threonyl-tRNA synthetase reveals extensive homology to the Escherichia coli and yeast enzymes

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)92906-6 ◽

1991 ◽

Vol 266 (15) ◽

pp. 9919-9923

Author(s):

M.E. Cruzen ◽

S.M. Arfin

Keyword(s):

Escherichia Coli ◽

Amino Acid ◽

Amino Acid Sequence ◽

Trna Synthetase

Download Full-text

Purification and partial amino acid sequence of a glutamyl-tRNA synthetase from Rhizobium meliloti

Biochemistry and Cell Biology ◽

10.1139/o89-101 ◽

1989 ◽

Vol 67 (10) ◽

pp. 674-679 ◽

Cited By ~ 3

Author(s):

Serge Laberge ◽

Manon Belair ◽

Alain Verreault ◽

Alexander W. Bell ◽

Lucien M. Bordeleau ◽

...

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Metabolic Regulation ◽

Rhizobium Meliloti ◽

Reversed Phase ◽

Trna Synthetase ◽

Partial Amino Acid Sequence ◽

Amino Terminal ◽

Internal Peptide ◽

Single Polypeptide

A glutamyl-tRNA synthetase has been purified to homogeneity from Rhizobium meliloti, using reversed-phase chromatography as the last step. Amino acid sequencing of the amino-terminal region of the enzyme indicates that it contains a single polypeptide, whose molecular weight is about 54 000, as judged by SDS–gel electrophoresis. The primary structures of the amino-terminus region and of an internal peptide obtained by cleavage of the enzyme with CNBr have similarities of 58 and 48% with regions of the glutamyl-tRNA sythetase of Escherichia coli; these are thought to be involved in the binding of ATP and tRNA, respectively. The small amount of glutamyl-tRNA synthetase present in R. meliloti is consistent with the metabolic regulation of the biosynthesis of many aminoacyl-tRNA synthetases.Key words: glutamyl-tRNA synthetase, Rhizobium meliloti, purification, reverse-phase chromatography, amino acid sequence.

Download Full-text

Overproduction and domain structure of the glutamyl-tRNA synthetase of Escherichia coli

Biochemistry and Cell Biology ◽

10.1139/o89-065 ◽

1989 ◽

Vol 67 (8) ◽

pp. 404-410 ◽

Cited By ~ 7

Author(s):

Anne Brisson ◽

Yves V. Brun ◽

Alexander W. Bell ◽

Paul H. Roy ◽

Jacques Lapointe

Keyword(s):

Escherichia Coli ◽

Amino Acid ◽

Amino Acid Sequence ◽

Domain Structure ◽

Sequence Similarity ◽

Trna Synthetase ◽

Amino Acid Sequence Similarity ◽

Structural Domains ◽

E Coli ◽

Domain Structures

The charging of glutamate on tRNAGlu is catalyzed by glutamyl-tRNA synthetase, a monomer of 53.8 kilodaltons in Escherichia coli. To obtain the large amounts of enzyme necessary for the identification of structural domains, we have inserted the structural gene gltX in the conditional runaway-replication plasmid pOU61, which led to a 350-fold overproduction of glutamyl-tRNA synthetase. Partial proteolysis of this enzyme revealed the existence of preferential sites of attack that, according to their N-terminal sequences, delimit regions of 12.9, 2.3, 12.1, and 26.5 kilodaltons from the N- to C-terminal of the enzyme. Their sizes suggest that the 2.3-kilodalton fragment is a hinge structure, and that those of 12.9, 12.1, and 26.5 kilodaltons are domain structures. The 12.9-kilodalton domain of the glutamyl-tRNA synthetase of E. coli is the only long region of this enzyme displaying a good amino acid sequence similarity with the glutaminyl-tRNA synthetase of Escherichia coli.Key words: glutamyl-tRNA synthetase, structural domains, overproduction, runaway-replication plasmid, Escherichia coli.

Download Full-text