Crystal structures of the archaeal RNase P protein Rpp38 in complex with RNA fragments containing a K-turn motif

In this study, the crystal structure of PhoRpp38 in complex with the K-turn in P12.2 was improved to 2.1   Å resolution and the structure of PhoRpp38 in complex with the K-turn in P12.1 was also determined at a resolution of 3.1   Å . Both structures revealed that Lys35, Asn38 and Glu39 in PhoRpp38 interact with characteristic G · A and A · G pairs in the K-turn, while Thr37, Asp59, Lys84, Glu94, Ala96 and Ala98 in PhoRpp38 interact with the three-nucleotide bulge in the K-turn. Moreover, an extended stem-loop containing P10 – P12.2 in complex with PhoRpp38, as well as PhoRpp21 and PhoRpp29, which are the archaeal homologues of the human proteins Rpp21 and Rpp29, respectively, was affinity-purified and crystallized. The crystals thus grown diffracted to a resolution of 6.35   Å . Structure determination of the crystals will demonstrate the previously proposed secondary structure of stem-loops including helices P12.1 and P12.2 and will also provide insight into the structural organization of the specificity domain in P. horikoshii RNase P RNA.

Source: Acta Crystallographica Section F - December 23, 2017 Category: Biochemistry Authors: Oshima, K. Gao, X. Hayashi, S. Ueda, T. Nakashima, T. Kimura, M. Tags: archaea K-turn L7Ae family Pyrococcus horikoshii ribonuclease P research communications Source Type: research