TY - JOUR
T1 - The [4Fe-4S] cluster of sulfurtransferase TtuA desulfurizes TtuB during tRNA modification in Thermus thermophilus
AU - Chen, Minghao
AU - Ishizaka, Masato
AU - Narai, Shun
AU - Horitani, Masaki
AU - Shigi, Naoki
AU - Yao, Min
AU - Tanaka, Yoshikazu
N1 - Funding Information:
X-ray diffraction experiments were conducted at the Photon Factory (proposals 2016G092 and 2015G067) and SPring-8 (proposals 2015B2114, 2015B2117, 2015B6524, and 2016B2565). We thank the beamline staff of SPring-8 and Photon Factory for their assistance. This work was supported by the Platform Project for Supporting Drug Discovery and Life Science Research (Basis for Supporting Innovative Drug Discovery and Life Science Research; BINDS) from the Japan Agency for Medical Research and Development grant number JP18am0101071 (to M.Y.), Hokkaido University Special Educational Program “Nitobe Scool” PKF8618101 (to M.I.), JST PRESTO JPMJPR1517 (to Y.T.), and Grants-in-Aid for Scientific Research (15J01961, to M.C.; 24000011, 19H02519, 19H03511, 19H03040, 19H02831, 19H00918, Bilateral Programs, and 19H02519, to Y.T.; 17H05424, to M.Y.; and 17H06955 and 18H02412 to M.H.) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan; and NEDO (to Y.T.).
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - TtuA and TtuB are the sulfurtransferase and sulfur donor proteins, respectively, for biosynthesis of 2-thioribothymidine (s2T) at position 54 of transfer RNA (tRNA), which is responsible for adaptation to high temperature environments in Thermus thermophilus. The enzymatic activity of TtuA requires an iron-sulfur (Fe-S) cluster, by which a sulfur atom supplied by TtuB is transferred to the tRNA substrate. Here, we demonstrate that the Fe-S cluster directly receives sulfur from TtuB through its inherent coordination ability. TtuB forms a [4Fe-4S]-TtuB intermediate, but that sulfur is not immediately released from TtuB. Further desulfurization assays and mutation studies demonstrated that the release of sulfur from the thiocarboxylated C-terminus of TtuB is dependent on adenylation of the substrate tRNA, and the essential residue for TtuB desulfurization was identified. Based on these findings, the molecular mechanism of sulfur transfer from TtuB to Fe-S cluster is proposed.
AB - TtuA and TtuB are the sulfurtransferase and sulfur donor proteins, respectively, for biosynthesis of 2-thioribothymidine (s2T) at position 54 of transfer RNA (tRNA), which is responsible for adaptation to high temperature environments in Thermus thermophilus. The enzymatic activity of TtuA requires an iron-sulfur (Fe-S) cluster, by which a sulfur atom supplied by TtuB is transferred to the tRNA substrate. Here, we demonstrate that the Fe-S cluster directly receives sulfur from TtuB through its inherent coordination ability. TtuB forms a [4Fe-4S]-TtuB intermediate, but that sulfur is not immediately released from TtuB. Further desulfurization assays and mutation studies demonstrated that the release of sulfur from the thiocarboxylated C-terminus of TtuB is dependent on adenylation of the substrate tRNA, and the essential residue for TtuB desulfurization was identified. Based on these findings, the molecular mechanism of sulfur transfer from TtuB to Fe-S cluster is proposed.
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U2 - 10.1038/s42003-020-0895-3
DO - 10.1038/s42003-020-0895-3
M3 - Article
C2 - 32265486
AN - SCOPUS:85083062234
VL - 3
JO - Communications Biology
JF - Communications Biology
SN - 2399-3642
IS - 1
M1 - 168
ER -