1H4M

Sulfurtransferase from Azotobacter vinelandii in complex with phosphate

Summary for 1H4M

• Entry DOI: 10.2210/pdb1h4m/pdb
• Related: 1E0C 1H4K
• Descriptor: PUTATIVE THIOSULFATE SULFURTRANSFERASE, 1,2-ETHANEDIOL (3 entities in total)
• Functional Keywords: transferase, sulfur metabolism, thiosulfate:cyanide
• Biological source: AZOTOBACTER VINELANDII
• Total number of polymer chains: 1
• Total formula weight: 29788.55

Authors

Bordo, D.,Forlani, F.,Spallarossa, A.,Colnaghi, R.,Carpen, A.,Pagani, S.,Bolognesi, M. (deposition date: 2001-05-11, release date: 2002-05-16, Last modification date: 2023-12-13)

Primary citation

Bordo, D.,Forlani, F.,Spallarossa, A.,Colnaghi, R.,Carpen, A.,Bolognesi, M.,Pagani, S.
A Persulfurated Cysteine Promotes Active Site Reactivity in Azotobacter Vinelandii Rhodanse
Biol.Chem., 382:1245-, 2001

PubMed Abstract: Active site reactivity and specificity of RhdA, a thiosulfate:cyanide sulfurtransferase (rhodanese) from Azotobacter vinelandii, have been investigated through ligand binding, site-directed mutagenesis, and X-ray crystallographic techniques, in a combined approach. In native RhdA the active site Cys230 is found persulfurated; fluorescence and sulfurtransferase activity measurements show that phosphate anions interact with Cys230 persulfide sulfur atom and modulate activity. Crystallographic analyses confirm that phosphate and hypophosphite anions react with native RhdA, removing the persulfide sulfur atom from the active site pocket. Considering that RhdA and the catalytic subunit of Cdc25 phosphatases share a common three-dimensional fold as well as active site Cys (catalytic) and Arg residues, two RhdA mutants carrying a single amino acid insertion at the active site loop were designed and their phosphatase activity tested. The crystallographic and functional results reported here show that specific sulfurtransferase or phosphatase activities are strictly related to precise tailoring of the catalytic loop structure in RhdA and Cdc25 phosphatase, respectively.

PubMed: 11592406
DOI: 10.1515/BC.2001.155

Experimental method

X-RAY DIFFRACTION (2.1 Å)