6BEV

Human Single Domain Sulfurtranferase TSTD1

Summary for 6BEV

• Entry DOI: 10.2210/pdb6bev/pdb
• Descriptor: Thiosulfate sulfurtransferase/rhodanese-like domain-containing protein 1 (2 entities in total)
• Functional Keywords: sulfurtransferase, transferase
• Biological source: Homo sapiens (Human)
• Total number of polymer chains: 2
• Total formula weight: 29431.17

Authors

Motl, N.,Akey, D.L.,Smith, J.L.,Banerjee, R. (deposition date: 2017-10-25, release date: 2018-01-24, Last modification date: 2024-03-13)

Primary citation

Libiad, M.,Motl, N.,Akey, D.L.,Sakamoto, N.,Fearon, E.R.,Smith, J.L.,Banerjee, R.
Thiosulfate sulfurtransferase-like domain-containing 1 protein interacts with thioredoxin.
J. Biol. Chem., 293:2675-2686, 2018

PubMed Abstract: Rhodanese domains are structural modules present in the sulfurtransferase superfamily. These domains can exist as single units, in tandem repeats, or fused to domains with other activities. Despite their prevalence across species, the specific physiological roles of most sulfurtransferases are not known. Mammalian rhodanese and mercaptopyruvate sulfurtransferase are perhaps the best-studied members of this protein superfamily and are involved in hydrogen sulfide metabolism. The relatively unstudied human thiosulfate sulfurtransferase-like domain-containing 1 (TSTD1) protein, a single-domain cytoplasmic sulfurtransferase, was also postulated to play a role in the sulfide oxidation pathway using thiosulfate to form glutathione persulfide, for subsequent processing in the mitochondrial matrix. Prior kinetic analysis of TSTD1 was performed at pH 9.2, raising questions about relevance and the proposed model for TSTD1 function. In this study, we report a 1.04 Å resolution crystal structure of human TSTD1, which displays an exposed active site that is distinct from that of rhodanese and mercaptopyruvate sulfurtransferase. Kinetic studies with a combination of sulfur donors and acceptors reveal that TSTD1 exhibits a low for thioredoxin as a sulfane sulfur acceptor and that it utilizes thiosulfate inefficiently as a sulfur donor. The active site exposure and its interaction with thioredoxin suggest that TSTD1 might play a role in sulfide-based signaling. The apical localization of TSTD1 in human colonic crypts, which interfaces with sulfide-releasing microbes, and the overexpression of TSTD1 in colon cancer provide potentially intriguing clues as to its role in sulfide metabolism.

PubMed: 29348167
DOI: 10.1074/jbc.RA117.000826

Experimental method

X-RAY DIFFRACTION (1.043 Å)