1y42 is a 1 chain structure with sequence from Neurospora crassa. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
We determined a 1.95 A X-ray crystal structure of a C-terminally truncated Neurospora crassa mitochondrial tyrosyl-tRNA synthetase (CYT-18 protein) that functions in splicing group I introns. CYT-18's nucleotide binding fold and intermediate alpha-helical domains superimpose on those of bacterial TyrRSs, except for an N-terminal extension and two small insertions not found in nonsplicing bacterial enzymes. These additions surround the cyt-18-1 mutation site and are sites of suppressor mutations that restore splicing, but not synthetase activity. Highly constrained models based on directed hydroxyl radical cleavage assays show that the group I intron binds at a site formed in part by the three additions on the nucleotide binding fold surface opposite that which binds tRNATyr. Our results show how essential proteins can progressively evolve new functions.
A tyrosyl-tRNA synthetase adapted to function in group I intron splicing by acquiring a new RNA binding surface.,Paukstelis PJ, Coon R, Madabusi L, Nowakowski J, Monzingo A, Robertus J, Lambowitz AM Mol Cell. 2005 Feb 4;17(3):417-28. PMID:15694342[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑ Paukstelis PJ, Coon R, Madabusi L, Nowakowski J, Monzingo A, Robertus J, Lambowitz AM. A tyrosyl-tRNA synthetase adapted to function in group I intron splicing by acquiring a new RNA binding surface. Mol Cell. 2005 Feb 4;17(3):417-28. PMID:15694342 doi:10.1016/j.molcel.2004.12.026