Dual activity of certain HIT-proteins: A. thaliana Hint4 and C. elegans DcpS act on adenosine 5'-phosphosulfate as hydrolases (forming AMP) and as phosphorylases (forming ADP).
Histidine triad (HIT)-family proteins interact with different mono- and dinucleotides and catalyze their hydrolysis. During a study of the substrate specificity of seven HIT-family proteins, we have shown that each can act as a sulfohydrolase, catalyzing the liberation of AMP from adenosine 5'-phosphosulfate (APS or SO(4)-pA). However, in the presence of orthophosphate, Arabidopsis thaliana Hint4 and Caenorhabditis elegans DcpS also behaved as APS phosphorylases, forming ADP. Low pH promoted the phosphorolytic and high pH the hydrolytic activities. These proteins, and in particular Hint4, also catalyzed hydrolysis or phosphorolysis of some other adenylyl-derivatives but at lower rates than those for APS cleavage. A mechanism for these activities is proposed and the possible role of some HIT-proteins in APS metabolism is discussed.
Guranowski
Andrzej
A
Department of Biochemistry and Biotechnology, The University of Life Sciences, Poznań, Poland. guranow@au.poznan.pl
Wojdyła
Anna Maria
AM
Zimny
Jarosław
J
Wypijewska
Anna
A
Kowalska
Joanna
J
Jemielity
Jacek
J
Davis
Richard E
RE
Bieganowski
Paweł
P
D000244:Adenosine Diphosphate / Q000096:biosynthesis; D000249:Adenosine Monophosphate / Q000096:biosynthesis; D000250:Adenosine Phosphosulfate / Q000378:metabolism*; D000818:Animals; D017360:Arabidopsis / Q000201:enzymology*; D029681:Arabidopsis Proteins; D017173:Caenorhabditis elegans / Q000201:enzymology*; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006867:Hydrolases / Q000378:metabolism*; D006868:Hydrolysis; D009097:Multienzyme Complexes / Q000378:metabolism*; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D010766:Phosphorylation; D011755:Pyrophosphatases / Q000378:metabolism*; D013379:Substrate Specificity; D013429:Sulfatases / Q000378:metabolism*
D029681:Arabidopsis Proteins; D029742:Caenorhabditis elegans Proteins; D009097:Multienzyme Complexes; C097552:histidine triad protein; D000249:Adenosine Monophosphate; D000250:Adenosine Phosphosulfate; D000244:Adenosine Diphosphate; D006867:Hydrolases; D010744:Phosphoric Monoester Hydrolases; D013429:Sulfatases; D011755:Pyrophosphatases; C509343:dcs-1 protein, C elegans; C546431:Hint4 protein, Arabidopsis