Difference between revisions of "Phosphatase Superfamily Cys-based III"

Revision as of 01:11, 16 June 2014

Phosphatase Classification: Superfamily Cys-based II

This superfamily has a unique fold, but shares the common CX5R catalytic motif with another two cysteine-based superfamilies, superfamily Cys-based I and superfamily Cys-based II.

The superfamily consists of two member families present in human low molecular weight PTP (LWMPTP) and SSU72. Despite having only 15% sequence identity, human LMWPTP and SSU72 structures superimpose with an rmsd of 1.7 Å [1].

A third family, arsenate reductase (ArsC) [2], is only found in prokaryotes. While known to reduce arsenate to arsenite (a similar reaction to the phosphatase reaction), the B. subtilis gene also has in vitro phosphatase activity. A different phosphatase fold, CDC25/Rhodanese also has members in plants and yeast (ACR2) that are capable of arsenate reductase activity, highlighting the similarity of the protein phosphatase and arsenate reductase activities.

Reference

1. Zhang Y, Zhang M, and Zhang Y. Crystal structure of Ssu72, an essential eukaryotic phosphatase specific for the C-terminal domain of RNA polymerase II, in complex with a transition state analogue. Biochem J. 2011 Mar 15;434(3):435-44. DOI:10.1042/BJ20101471 | PubMed ID:21204787 | HubMed [zhangy11]
2. Bennett MS, Guan Z, Laurberg M, and Su XD. Bacillus subtilis arsenate reductase is structurally and functionally similar to low molecular weight protein tyrosine phosphatases. Proc Natl Acad Sci U S A. 2001 Nov 20;98(24):13577-82. DOI:10.1073/pnas.241397198 | PubMed ID:11698660 | HubMed [Bennett]