Phosphorylated amino acid

Zu, X.L., BesanL P.G., Imhof, A. and Attwood, P.V. (2007) Mass spectrometric analysis of protein histidine phosphorylation. Amino Acids,... 

Phosphorylated amino acids move in the order serine phosphate > threonine phosphate > tyrosine phosphate. 

Phosphorylation triggers a second series of events. Phosphorylated amino acids residues act as docking sites for a number of intracellular proteins. These proteins contain their own amino acid motifs that recognize and bind to one or another of the phosphorylated amino acids. Some of these proteins have additional domains that now become activated and bind to other signaling molecules. A complex of proteins is thus assembled at the surface of the cell and specific signaling... 

In contrast to the inherent limitations of synthesis in solution, solid-phase peptide synthesis provides a key method for the generation of many large and complex peptides. The application of phosphorylated amino acids to solid-phase methodology has been the subject of particular interest in consideration of the synthetic potential of this approach for the rapid and routine preparation of complex phosphopeptides. Unlike other amino acids, the generation of Ser(F)- and Thr(P)-peptides is complicated due to the sensitivity of these residues to harsh acid or base conditions and the selection of suitable phosphate derivatives that are compatible with solid-phase peptide synthesis. 

FIGURE 27-29 Some modified amino acid residues, (a) Phosphorylated amino acids, (b) A carboxylated amino acid, (c) Some methylated amino acids. 

Little is known about the mechanism of action of the purple acid phosphatase. The beef spleen enzyme as isolated contains one tightly bound phosphate,821 but it is not certain whether this corresponds to a phosphorylated amino acid residue as found for other phosphatases. Addition of phosphate causes a shift in the visible spectrum of the enzyme. 

CONTENTS Acknowledgments, Margery G. Ord and Lloyd A. Stocken. Introduction. Biochemistry Before 1900. Early Metabolic Studies Energy Needs and the Composition of the Diet. Carbohydrate Utilization Glycolysis and Related Activities. Aspects of Carbohydrate Oxidation, Electron Transfer, and Oxidative Phosphorylation. Amino Acid Catabolism in Animals. The Utilization of Fatty Acids. The Impact of Isotopes 1925-1965. Biochemistry and the Cell. Concepts of protein Structure and Function. Chronological Summary of Main Events Up to ca. 1960. Principal Metabolic Pathways. Index. 

In the study of phosphoproteins, high-affinity antiphosphotyrosine (and other phosphorylated amino acid) antibodies can be used for phosphoprotein enrichment with peptide mass and sequence analyses are used to identify phosphorylation sites (40-43). 

Because of their abilities in both peptide and nucleic acid oligomerization, N-phosphoryl amino acids could have played an important role in prebiotic chemistry on condition that a plausible pathway of synthesis of these compounds is made available. 

It has a broad substrate specificity [60], but the preferred amino acid sequence around the phosphorylated serine or threonine includes a pair of basic amino acids on the amino terminus side [60], Two arginine residues removed by one residue from the phosphorylated amino acid or a Lys-Arg sequence removed by two residues are preferred. 

Key Words P-31 solid-state NMR, 31P CP/MAS, Ultra-fast MAS, Phosphorylated amino acids, Nucleotides, Nucleic acids, Phosphate glasses, Aluminophosphates, Molecular sieves, Catalysts, Polyoxometalate (POM), Metal-organic framework (MOF), Inclusion complexes. 

TABLE 1 The values of the principal elements of the chemical shift tensor for selected O-phosphorylated amino acids obtained from the analysis of the intensities of the spinning sidebands 31P CP/MAS spectra... 

The correlation of 31P, <5 , Ad and Q parameters versus the intermolecular P-O H-O-C and P-O- H-O-P hydrogen bond distance in the L and DL forms of O-phosphorylated amino acids has been presented (see Figure 15A). Somewhat unexpectedly, these two groups of compounds reveal opposite trends when the hydrogen-bond strength decreases the Sllr AS, and Q values increase and the d33 decreases for the L form, with a reverse scenario taking place in the case of the DL form. 

The orientation of 31P <5 in the L-enantiomer of phosphorylated amino acids has been determined on the basis of theoretical calculations. According to... 

On the other hand, a particular protein function can be realized with different protein folds, and an example of this are protein phosphatases. Protein phosphatases feature two distinctively different catalytic mechanisms for hydrolytically cleaving phosphorylated amino acid residues. The active sites of serine/threonine protein phosphatases (PPs) contain two metal centers that directly activate a water molecule for nucleophilic attack of the phosphate ester bond. In contrast, protein tyrosine phosphatases (PTPs) [105] possess a Cys residue present in the active site loop containing the conserved PTP signature motif HCXXXXXRS. The Cys sidechain acts as the attacking nucleophile in the formation of a phosphocysteine intermediate, which is eventually hydrolyzed by a water molecule [106], The same catalytic mechanism is also shared by dual-specificity phosphatases (see below). 

Recently, a small molecule fluorophore phosphosensor technology referred as Pro-Q Diamond dye has been developed to detect and quantitate phosphorylated amino acids within peptides and proteins in microarrays. ° In addition to binding assays, fluorescence detection methods have also been developed for functional assays. For example, microarrays of quenched fluorescent substrates can be used to detect protease or esterase activities in the analytes. In this method, quenched fluorescent substrates are prepared by coupling the peptide substrate to coumarin, a fluorescent dye. These peptide substrates are then spotted onto the solid support... 

C-racemization of phosphorothioylated/phosphorylated amino acids (Scheme 23). An oxathiaphospholane approach to one-pot phosphorothioylation of isoprenoid alcohols such as allyl, geranyl, isopentenyl, citronellyl, farnesyl, and phytyl alcohols has also been reported (Scheme 24). ... 

Another important hydrolytic enzyme of the gut is acid phosphatase. Like enterokinase, it is bound to the enterocyte facing the lumen and is present in the duodenum, jejunum, and ileum. Alkaline phosphatase, a zinc metalloenzyme, also occurs in the gut. Acid phosphatase and alkaline phosphatase catalyze the removal of phosphate groups from a wide variety of compounds in foods, for example, sugar phosphates, triose phosphates, nucleotides such as AMP, ADP, and ATP, pyrophosphate, and phosphorylated amino acids. A number of sugar and triose phosphates are described in the section on glycolysis in Chapter 4. 

Sequence information can also be obtained using Edman degradation to remove amino-terminal residues from a peptide, to produce a collection of peptides. MALDI-TOF can then be used to obtain the peptides masses, and the sequence determined by mass difference between consecutive peptides. This methodology is called protein ladder sequencing, and allows information to be obtained for up to 30 residues. This method is useful for the identification of posttranslational modifications, such as phosphorylated amino acid residues.24... 

Cell or tissue type Peptide tested Size, location of phosphoprotein Phosphorylated amino acid Reference... 

---