例如:"lncRNA", "apoptosis", "WRKY"

Structural and biochemical characterization of Siw14: A protein-tyrosine phosphatase fold that metabolizes inositol pyrophosphates.

J Biol Chem. 2018 May 04;293(18):6905-6914. Epub 2018 Mar 14
{{ author.authorName }}{{getOrganisationIndexOf(author)}} {{ author.authorName }}{{getOrganisationIndexOf(author)}}
{{ author.authorName }}{{getOrganisationIndexOf(author)}} {{ author.authorName }}{{getOrganisationIndexOf(author)}}
+ et al

[No authors listed]

Author information
  • {{index+1}} {{ organisation }}

摘要


Inositol pyrophosphates (PP-InsPs) are "energetic" intracellular signals that are ubiquitous in animals, plants, and fungi; structural and biochemical characterization of PP-InsP metabolic enzymes provides insight into their evolution, reaction mechanisms, and regulation. Here, we describe the 2.35-Å-resolution structure of the catalytic core of Siw14, a 5-PP-InsP phosphatase from Saccharomyces cerevisiae and a member of the protein tyrosine-phosphatase (PTP) superfamily. Conclusions that we derive from structural data are supported by extensive site-directed mutagenesis and kinetic analyses, thereby attributing new functional significance to several key residues. We demonstrate the high activity and exquisite specificity of Siw14 for the 5-diphosphate group of PP-InsPs. The three structural elements that demarcate a 9.2-Å-deep substrate-binding pocket each have spatial equivalents in PTPs, but we identify how these are specialized for Siw14 to bind and hydrolyze the intensely negatively charged PP-InsPs. (a) The catalytic P-loop with the CX5R(S/T) PTP motif contains additional, positively charged residues. (b) A loop between the α5 and α6 helices, corresponding to the Q-loop in PTPs, contains a lysine and an arginine that extend into the catalytic pocket due to displacement of the α5 helix orientation through intramolecular crowding caused by three bulky, hydrophobic residues. (c) The general-acid loop in PTPs is replaced in Siw14 with a flexible loop that does not use an aspartate or glutamate as a general acid. We propose that an acidic residue is not required for phosphoanhydride hydrolysis.

KEYWORDS: {{ getKeywords(articleDetailText.words) }}

基因功能


  • {{$index+1}}.{{ gene }}

图表


原始数据


 保存测序数据
Sample name
Organism Experiment title Sample type Library instrument Attributes
{{attr}}
{{ dataList.sampleTitle }}
{{ dataList.organism }} {{ dataList.expermentTitle }} {{ dataList.sampleType }} {{ dataList.libraryInstrument }} {{ showAttributeName(index,attr,dataList.attributes) }}

文献解读