Disease relevance of proS

• Its proS gene was cloned and the gene product overexpressed in Escherichia coli [1].

High impact information on proS

• The existence of this protein contrasts with proposals that aminoacylation with cysteine in M. jannaschii is an auxiliary function of a canonical prolyl-tRNA synthetase [2].
• The R197 M mutant enzyme catalyzed removal of the proS hydrogen atom from (4'R)-[(3)H]PMP, showing that the guanidinium side-chain plays an important role in determining stereospecificity [3].
• To identify potential acceptor stem contacts made by Escherichia coli prolyl-tRNA synthetase (ProRS), an enzyme of unknown structure, we performed cysteine-scanning mutagenesis in the motif 2 loop [4].
• Our data suggest that the two ProRS groups may reflect coadaptations needed to accommodate changes in the operational RNA code for proline [5].
• We establish that the drpA gene has been successfully cloned and describe the fine-structure map of three drpA-(Ts) mutations as well as the complete nucleotide sequence of the drpA gene [6].

Biological context of proS

• We identified a major sigma-70 promoter for the drpA gene on the bases of (i) its similarity to the consensus sequence and (ii) S1 protection and primer extension mapping data [6].
• The plasmid has been used to clone part of a homologue of the E. coli drpA gene, encoding a global regulatory element for RNA synthesis [7].
• Alignment of all known ProRS primary sequences from different species reveals particularly low overall sequence homology, as well as two distinct groups of enzymes [8].

Anatomical context of proS

• The possibility that the largest subunit of the mammalian high-M(r) complexes may be a bifunctional protein encoding both glutamyl- and prolyl-tRNA synthetase activities is considered and discussed in light of the recently published sequence of the corresponding polypeptide from HeLa cells [9].

References