Structural highlights
Function
[NTP2_TOXGO] May perform an important processing step in the conversion of high energy nucleotides prior to uptake by the parasite. NTPAse-II has a specific activity 4.5-fold lower than NTPAse-I in hydrolysis of ATP. The primary difference between these isozymes lies in their ability to hydrolyze nucleoside triphosphate versus diphosphate substrates. While NTPAse-II hydrolyzes ATP to ADP and ADP to AMP at almost the same rate, NTPAse-I hydrolyzes ADP to AMP at a much slower rate (0.7% of the rate for ATP).
Publication Abstract from PubMed
Toxoplasma gondii nucleoside triphosphate diphosphohydrolase (NTPDase) 1 was crystallized in an intermediate tetrameric conformation. The crystal structure is similar to that of T. gondii NTPDase3 and represents an inactive conformation as the activating disulfide bridge is not reduced and the active site cleft between the two domains of each monomer is open. However, the arrangement of the monomers within the tetramer differs from that of the inactive form of NTPDase3 and may represent an intermediate conformation on the path of the closure motion of the tetramer induced upon activation. (c) Proteins 2013;. (c) 2013 Wiley Periodicals, Inc.
The crystal structure of Toxoplasma gondii nucleoside triphosphate diphosphohydrolase 1 represents a conformational intermediate in the reductive activation mechanism of the tetrameric enzyme.,Krug U, Totzauer R, Strater N Proteins. 2013 Mar 22. doi: 10.1002/prot.24288. PMID:23526564[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Krug U, Totzauer R, Strater N. The crystal structure of Toxoplasma gondii nucleoside triphosphate diphosphohydrolase 1 represents a conformational intermediate in the reductive activation mechanism of the tetrameric enzyme. Proteins. 2013 Mar 22. doi: 10.1002/prot.24288. PMID:23526564 doi:10.1002/prot.24288
