title: Sequence, structure and evolutionary relationships between class 2 aminoacyl-tRNA synthetases: an update.
abstract: The seven class 2 aminoacyl-tRNA synthetases that are alpha 2 dimers have previously been divided by sequence homology into class 2a (seryl-, threonyl-, prolyl- and histidyl-) and class 2b (aspartyl-, asparaginyl- and lysyl-). It has been more difficult to classify the glycyl-, phenylalanyl- and alanyl-tRNA synthetases which have different subunit stoichiometries and which did not apparently contain all three canonical class 2 motifs. New sequence and structural information relating to the three problematic synthetases will be discussed permitting a step forward to be taken in the understanding of the evolutionary relationships between the class 2 synthetases.
authors.affiliation: EMBL Grenoble Outstation c/o ILL, France.
authors.forename: S
authors.initials: S
authors.lastname: Cusack
mesh_terms: D000595:Amino Acid Sequence; D000604:Amino Acyl-tRNA Synthetases / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000378:metabolism; D000818:Animals; D000926:Anticodon; D005075:Biological Evolution; D006801:Humans; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D012346:RNA, Transfer, Amino Acyl / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship
chemical_list: D000926:Anticodon; D012346:RNA, Transfer, Amino Acyl; D000604:Amino Acyl-tRNA Synthetases