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Acta Biochimica Polonica 1983Phosphoprotein phosphatase was isolated from yeast postribosomal supernatant and partly characterized. The enzyme preferentially dephosphorylated phospho-casein and...
Phosphoprotein phosphatase was isolated from yeast postribosomal supernatant and partly characterized. The enzyme preferentially dephosphorylated phospho-casein and acidic ribosomal proteins L44 and L45, the eukaryotic analogues of bacterial proteins L7 and L12. The evidence suggests that this enzyme is not a catalytic subunit of the multifunctional phosphoprotein phosphatase present in most eukaryotic organisms.
Topics: Fungal Proteins; Hydrogen-Ion Concentration; Phosphoprotein Phosphatases; Ribosomal Proteins; Saccharomyces cerevisiae
PubMed: 6306965
DOI: No ID Found -
Circulation Research Apr 2005
Topics: Animals; Calcium; Calcium-Binding Proteins; Calcium-Transporting ATPases; Cardiomegaly; Enzyme Inhibitors; Genetic Therapy; Heart Failure; Mice; Phosphoprotein Phosphatases; Protein Phosphatase 1; Proteins; Sarcoplasmic Reticulum Calcium-Transporting ATPases
PubMed: 15831821
DOI: 10.1161/01.RES.0000164359.95588.25 -
The Journal of Biological Chemistry Sep 2004
Review
Topics: Amino Acid Sequence; Muscle Contraction; Muscle, Skeletal; Phosphoprotein Phosphatases
PubMed: 15136561
DOI: 10.1074/jbc.R400018200 -
FEBS Letters Sep 1978
Topics: Animals; Cyclic AMP; Egtazic Acid; Enzyme Activation; Glycogen Synthase; Ligands; Muscles; Phosphoprotein Phosphatases; Phosphorylase Kinase; Phosphorylase a; Phosphorylation; Protein Kinases; Rabbits
PubMed: 213308
DOI: 10.1016/0014-5793(78)81112-0 -
Advances in Lipid Research 1993
Review
Topics: Animals; Brain; Ceramides; Enzyme Activation; Ethers, Cyclic; Glioma; Humans; Okadaic Acid; Phosphoprotein Phosphatases; Protein Phosphatase 2
PubMed: 8396314
DOI: No ID Found -
Ukrainskii Biokhimicheskii Zhurnal... 1988CoA hydrolysis was studied by a homogenous phosphoprotein phosphatase (EC 3.1 3.16) preparation from bovine spleen nuclei at pH 5.8. Phosphoprotein phosphatase catalyzed...
CoA hydrolysis was studied by a homogenous phosphoprotein phosphatase (EC 3.1 3.16) preparation from bovine spleen nuclei at pH 5.8. Phosphoprotein phosphatase catalyzed hydrolysis of the CoA 3'-phosphoester bond to form dephospho-CoA and Pi. The Km value for phosphoprotein phosphatase with CoA as substrate was 3.7 mM, the specific activity - 0.26 mmol Pi.min-1.mg-1. Phosphoprotein phosphatase did not essentially catalyze the calcium pantothenate hydrolysis (not more than 2% as compared with the CoA hydrolysis rate).
Topics: Animals; Cattle; Chromatography, High Pressure Liquid; Coenzyme A; Hydrolysis; Kinetics; Phosphoprotein Phosphatases; Spleen
PubMed: 2849829
DOI: No ID Found -
The Biochemical Journal Mar 1959
Topics: Phosphoprotein Phosphatases; Phosphoric Monoester Hydrolases; Spleen; Substrate Specificity
PubMed: 13638262
DOI: 10.1042/bj0710537 -
ACS Chemical Biology Feb 2007Protein phosphatase 2A (PP2A) is a serine/threonine phosphatase implicated in cancer. Three new crystal structures of PP2A show how it interacts with inhibitory toxins... (Review)
Review
Protein phosphatase 2A (PP2A) is a serine/threonine phosphatase implicated in cancer. Three new crystal structures of PP2A show how it interacts with inhibitory toxins and with one of its regulatory subunits. The structures also explain how specific site mutations may lead to cancer and suggest a novel role for PP2A methylation in the formation of PP2A holoenzymes.
Topics: Amino Acid Substitution; Crystallography, X-Ray; Holoenzymes; Humans; Methylation; Neoplasms; Noxae; Phosphoprotein Phosphatases; Protein Conformation; Protein Phosphatase 2; Protein Subunits; Signal Transduction
PubMed: 17313179
DOI: 10.1021/cb700021z -
The FEBS Journal Feb 2021Protein phosphorylation is a major reversible post-translational modification. Protein phosphatases function as 'critical regulators' in signaling networks through... (Review)
Review
Protein phosphorylation is a major reversible post-translational modification. Protein phosphatases function as 'critical regulators' in signaling networks through dephosphorylation of proteins, which have been phosphorylated by protein kinases. A large understanding of their working has been sourced from animal systems rather than the plant or the prokaryotic systems. The eukaryotic protein phosphatases include phosphoprotein phosphatases (PPP), metallo-dependent protein phosphatases (PPM), protein tyrosine (Tyr) phosphatases (PTP), and aspartate (Asp)-dependent phosphatases. The PPP and PPM families are serine(Ser)/threonine(Thr)-specific phosphatases (STPs), while PTP family is Tyr specific. Dual-specificity phosphatases (DsPTPs/DSPs) dephosphorylate Ser, Thr, and Tyr residues. PTPs lack sequence homology with STPs, indicating a difference in catalytic mechanisms, while the PPP and PPM families share a similar structural fold indicating a common catalytic mechanism. The catalytic cysteine (Cys) residue in the conserved HCX R active site motif of the PTPs acts as a nucleophile during hydrolysis. The PPP members require metal ions, which coordinate the phosphate group of the substrate, followed by a nucleophilic attack by a water molecule and hydrolysis. The variable holoenzyme assembly of protein phosphatase(s) and the overlap with other post-translational modifications like acetylation and ubiquitination add to their complexity. Though their functional characterization is extensively reported in plants, the mechanistic nature of their action is still being explored by researchers. In this review, we exclusively overview the plant protein phosphatases with an emphasis on their mechanistic action as well as structural characteristics.
Topics: Biocatalysis; Catalytic Domain; Models, Molecular; Phosphoprotein Phosphatases; Phosphorylation; Plant Proteins; Protein Domains; Protein Subunits; Signal Transduction; Substrate Specificity
PubMed: 32542989
DOI: 10.1111/febs.15454 -
Trends in Plant Science Apr 2007Serine/threonine-specific phosphoprotein phosphatases (PPPs) are ubiquitous enzymes in all eukaryotes, but their regulatory functions are largely unknown in higher... (Review)
Review
Serine/threonine-specific phosphoprotein phosphatases (PPPs) are ubiquitous enzymes in all eukaryotes, but their regulatory functions are largely unknown in higher plants. The Arabidopsis genome encodes 26 PPP catalytic subunits related to type 1, type 2A and so-called novel phosphatases, including four plant-specific enzymes carrying large N-terminal kelch-domains, but no apparent homologue of the PP2B family. The catalytic subunits of PPPs associate with regulatory protein partners that target them to well defined cellular locations and modulate their activity. Recent studies of phosphatase partners and their interactions have directed attention again to functional dissection of plant PPP families, and highlight their intriguing roles in the regulation of metabolism, cell cycle and development, as well as their roles in light, stress and hormonal signalling.
Topics: Arabidopsis; Arabidopsis Proteins; Models, Biological; Nuclear Proteins; Phosphoprotein Phosphatases; Phylogeny; Protein Structure, Tertiary; Protein Subunits
PubMed: 17368080
DOI: 10.1016/j.tplants.2007.03.003