Phosphoryl Research Articles

A Single Point Mutation Controls the Rate of Interconversion Between the g + and g - Rotamers of the Histidine 189 χ2 Angle That Activates Bacterial Enzyme I for Catalysis.

Enzyme I (EI) of the bacterial phosphotransferase system (PTS) is a master regulator of bacterial metabolism and a promising target for development of a new class of broad-spectrum antibiotics. The catalytic activity of EI is mediated by several intradomain, interdomain, and intersubunit conformational equilibria. Therefore, in addition to its relevance as a drug target, EI is also a good model for investigating the dynamics/function relationship in multidomain, oligomeric proteins. Here, we use solution NMR and protein design to investigate how the conformational dynamics occurring within the N-terminal domain (EIN) affect the activity of EI. We show that the rotameric g +-to-g − transition of the active site residue His189 χ2 angle is decoupled from the state A-to-state B transition that describes a ∼90° rigid-body rearrangement of the EIN subdomains upon transition of the full-length enzyme to its catalytically competent closed form. In addition, we engineered EIN constructs with modulated conformational dynamics by hybridizing EIN from mesophilic and thermophilic species, and used these chimeras to assess the effect of increased or decreased active site flexibility on the enzymatic activity of EI. Our results indicate that the rate of the autophosphorylation reaction catalyzed by EI is independent from the kinetics of the g +-to-g − rotameric transition that exposes the phosphorylation site on EIN to the incoming phosphoryl group. In addition, our work provides an example of how engineering of hybrid mesophilic/thermophilic chimeras can assist investigations of the dynamics/function relationship in proteins, therefore opening new possibilities in biophysics.

Functional dissection of individual domains in group III histidine kinase Sshk1p from the phytopathogenic fungus Sclerotinia sclerotiorum

A conserved kinase domain and phosphoryl group receiver domain at the C-terminus and poly-HAMP domains at the N-terminus comprise the structural components of the group III HK which was considered as a potential antifungal target. However, the roles of individual domains in the function of group III HKs have rarely been dissected in fungi. In this study, we dissected the roles of individual domains to better understand the function of Sshk1p, a group III HK from Sclerotinia sclerotiorum. The results suggest that individual domains play different roles in the functionality of Sshk1p and are implicated in the regulation of mycelial growth, sclerotia formation, pathogenicity. And the mutants of each domain in Sshk1 showed significantly increased sensitivity to hyperosmotic stress. However, the mutants of each domain in Sshk1 showed high resistance to fludioxonil and dimethachlon which suggested that all nine domains of Sshk1p were indispensable for susceptibility to fludioxonil and dimethachlon. Moreover, deletion of each individual domain in Sshk1 cancelled intracellular glycerol accumulation and increased SsHog1p phosphorylation level triggered by NaCl and fludioxonil, suggesting that all the domains of Sshk1 were essential for Sshk1-mediated SsHog1p phosphorylation and subsequent polyol accumulation in response to fludioxonil and hyperosmotic stress.

Copper‐Phosphine Mediated Oxidative Phosphorylation of Aromatic Amines and P(OR)3 under Aerobic Conditions

AbstractA copper‐phosphine system (Cu(OAc)2 and t‐Bu3P⋅HBF4) was used to synthesize α‐aminophosphonates and phosphoramides from various aromatic amines and trialkyl phosphites under oxygen atmosphere. With this Cu−P system, α‐aminophosphonates containing C−P bonds were generated from N,N‐dimethylanilines or N‐methylanilines and trialkyl phosphites; phosphoramidates containing N−P bonds were produced from N‐benzylanilines and trialkyl phosphites. This strategy provided a convenient and efficient method for the synthesis of phosphorous compounds. The compounds containing phosphoryl group attracted extensive attention due to their biological activities and wide applications.[1,2] The α‐aminophosphonates have been applied in medicine and agriculture such as anticancer drugs, antibiotics, antibacterial agents, and enzyme inhibitors.[1] And phosphoramides could be served as antibiotics, prodrugs, flame retardants, and ligands.[2]

A novel grafted polyethylene with diphenyl phosphoryl group: Improved flame retardancy and favorable compatibility

AbstractA novel phosphorous/benzene‐containing flame‐retardant diphenyl phosphoryl polyethylene (PEP) is synthesized from ethylene vinyl acetate (EVA) copolymer with two steps reactions and its chemical structure is characterized by Fourier transform infrared and nuclear magnetic resonance spectroscopies. The grafted molecular dispersion is calculated by gel permeation chromatography and the phase transition is analyzed by differential scanning calorimetry. And results show its promising processability potential. High density polyethylene (HDPE) composite containing 15 wt% PEP is prepared by melt blending, and its fire performance and thermal behaviors are investigated in terms of limiting oxygen index (LOI), vertical burning (UL‐94) and thermogravimetric analysis. There is a 16% increase to 20.2 in the LOI value of PEP, while it fails the UL‐94 test. The char morphology is characterized by scanning electronic microscopy and observed multi‐layered intumescent residue char effectively reduces the transfer of heat and oxygen. The major degradation is quantitively analyzed by the Flynn‐Wall‐Ozawa method. The results demonstrate that there is a catalytic effect by the phosphorous substance in char formation. Finally, the mechanical properties tests show that the loss due to the addition is small, which signifies the good compatibility between the pure HDPE and the grafted addition.

The Divergent Key Residues of Two Agrobacterium fabrum (tumefaciens) CheY Paralogs Play a Key Role in Distinguishing Their Functions.

The chemotactic response regulator CheY, when phosphorylated by the phosphoryl group from phosphorylated CheA, can bind to the motor switch complex to control the flagellar motor rotation. Agrobacterium fabrum (previous name: Agrobacterium tumefaciens), a phytopathogen, carries two paralogous cheY genes, cheY1 and cheY2. The functional difference of two paralogous CheYs remains unclear. Three cheY-deletion mutants were constructed to test the effects of two CheYs on the chemotaxis of A. fabrum. Phenotypes of three cheY-deletion mutants show that deletion of each cheY significantly affects the chemotactic response, but cheY2-deletion possesses more prominent effects on the chemotactic migration and swimming pattern of A. fabrum than does cheY1-deletion. CheA-dependent cellular localization of two CheY paralogs and in vitro pull-down of two CheY paralogs by FliM demonstrate that the distinct roles of two CheY paralogs arise mainly from the differentiation of their binding affinities for the motor switch component FliM, agreeing with the divergence of the key residues on the motor-binding surface involved in the interaction with FliM. The single respective replacements of key residues R93 and A109 on the motor-binding surface of CheY2 by alanine (A) and valine (V), the corresponding residues of CheY1, significantly enhanced the function of CheY2 in regulating the chemotactic response of A. fabrum CheY-deficient mutant Δy to nutrient substances and host attractants. These results conclude that the divergence of the key residues in the functional subdomain is the decisive factor of functional differentiation of these two CheY homologs and protein function may be improved by the substitution of the divergent key residues in the functional domain for the corresponding residues of its paralogs. This finding will help us to better understand how paralogous proteins sub-functionalize. In addition, the acquirement of two CheY2 variants, whose chemotactic response functions are significantly improved, will be very useful for us to further explore the mechanism of CheY to bind and regulate the flagellar motor and the role of chemotaxis in the pathogenicity of A. fabrum.

Extracellular polymeric substances of acidophilic microorganisms play a crucial role in heavy metal ions adsorption

The influences of extracellular polymeric substances (EPS) on heavy metal ions biosorption by acidophilic microorganisms have not been systematically reported previously. In this study, three acidophilic strains were chosen as model microbes to evaluate the effect of EPS on the adsorption of heavy metal ions (Cu2+, Ni2+, Cd2+, Zn2+) from aqueous solutions. The results indicated that buffering capacities and protonation/deprotonation abilities of these acidophiles were enhanced in the presence of EPS. Acid–base titration and FTIR analysis revealed the carboxyl, phosphoryl, amino and hydroxyl groups have provided EPS binding sites for heavy metal ions via deprotonation. The extreme thermophilic archaea had the highest total site concentration of 7.93 ± 0.52 × 10−4 mol/g on the cell surface. Meanwhile, cells with EPS had better performance in adsorption when compared with cells without EPS. The biosorption abilities of the extreme thermophilic archaea with EPS toward Cu2+, Ni2+, Cd2+ and Zn2+ were 48 μmol/g, 37.5 μmol/g, 32.5 μmol/g and 28 μmol/g, respectively. This study could provide theoretical support for the treatment of heavy metal ions in acid mine drainage by acidophiles.

PEA‐15 Uses a Common Scaffold to Interact with Different Binding Partners in a Phosphorylation‐Dependent Manner

PEA-15, phosphoprotein enriched in astrocytes, 15 kDa, performs a variety of functions in regulating cellular pathways, such as cell proliferation and apoptosis. The protein consists of a death effector domain (DED) and a long, irregular structured C-terminal tail. We hypothesize that phosphorylation of the C-terminal tail residues, Ser-104 and Ser-116, promotes conformational changes at the DED, and alters the binding specificity from extracellular regulated kinase-2 (ERK2) to Fas associated death domain (FADD). To test the hypothesis, we used the molecular dynamics package, GROMACS, to simulate the complexes between unphosophorylated PEA-15 and ERK2, and doubly phosphorylated PEA-15 (PEA-15pp) and FADD on a GPU-equipped Linux workstation, with simulation time up to 150 ns. The simulated complex structures were analyzed and visualized with VMD and PyMOL programs. The computational experiments revealed that the DED conformations and surface polar interactions are dependent on phosphorylation states of the C-terminal serine residues. The binding interfaces between PEA-15 and ERK and PEA-15pp and FADD are similarly composed of a scaffold that includes both DED and C-terminal tail residues of PEA-15. Residues from helices 5 and 6 of the DED directly interact with either ERK2 or FADD, while helices 2, 3, and 4 become more flexible in the complex structures than the free-form protein. PEA-15 also uses the same stretch of its irregular C-terminal tail to interact with FADD or ERK2 (residues 116-130). Phosphorylation of Ser-104 and Ser-116 on the C-terminal tail alters the binding specificity from ERK2 to FADD, as the negatively charged phosphoryl groups interacts with positively charged amino acids on FADD, while there are no charge-charge interactions of the C-terminal tail with ERK2.

Does the basicity of phosphoryl oxygen change with alkyl chain length in phosphate ligands?

The effect of alkyl chain length on the basicity of phosphoryl oxygen in phosphate ligands is investigated in the present study. In all ligands except PH3O, a negative hyperconjugation interaction has been observed resulting from the interaction between the filled π (PO) and σ*(PR) orbitals. This hyperconjugation interaction reduces the phosphoryl group’s electron density and is found identical in all ligands. The NBO, AIM and ELF electronic structure analysis revealed no evidence for the correlation between the basicity of phosphoryl oxygen atom and alkyl chain length in phosphate ligands.

Calixresorcin[4]arene-Mediated Transport of Pb(II) Ions through Polymer Inclusion Membrane.

A facilitated transport of Pb(II) through polymer inclusion membrane (PIM) containing 1,8,15,22-tetra(1-heptyl)-calixresorcin[4]arene and its tetra- and octasubstituted derivatives containing phosphoryl, thiophosphoryl or ester groups as an ion carrier was investigated. The efficiency of Pb(II) removal from aqueous nitrate solutions was considered as a function of the composition of membrane (effect of polymer, plasticizer, and carrier), feed (effect of initial metal concentration and presence of other metal ions) and stripping phases, and temperature of the process conducting. Two kinetic models were applied for the transport description. The highest Pb(II) ions removal efficiency was obtained for the membrane with tetrathiophosphorylated heptyl-calixresorcin[4]arene as an ion carrier. The activation energy value, found from Eyring plot to be equal 38.7 ± 1.3 kJ/mol, suggests that the transport process is controllable both by diffusion and chemical reaction. The competitive transport of Pb(II) over Zn(II), Cd(II), and Cr(III) ions across PIMs under the optimal conditions was also performed. It was found that the Cr(III) ions’ presence in the feed phase disturb effective re-extraction of Pb(II) ions from membrane to stripping phase. Better stability of PIM-type than SLM-type membrane was found.

A Radical Reimagining of Fungal Two-Component Regulatory Systems.

Bacterial two-component regulatory systems (TCSs) mediate signal transduction by transferring phosphoryl groups between sensor kinase and response regulator proteins, sometimes using intermediary histidine-phosphotransferase (Hpt) domains to form multistep phosphorelays. Because (i) almost all known fungal sensor kinases exhibit a domain architecture characteristic of bacterial TCS phosphorelays, (ii) all known fungal Hpts are stand-alone proteins suited to shuttle between cytoplasm and nucleus, and (iii) the best-characterized fungal TCS is a canonical phosphorelay, it is widely assumed that most or all fungal TCSs function via phosphorelays. However, fungi generally encode more sensor kinases than Hpts or response regulators, leading to a disparity between putative phosphorelay inputs and outputs. The simplest resolution of this paradox is to hypothesize that most fungal sensor kinases do not participate in phosphorelays. Reimagining how fungal TCSs might function leads to multiple testable predictions.

Crystal structure of the DNA-binding domain of Bacillus subtilis CssR

Bacteria utilize two-component systems to regulate gene expression in response to changes in environmental stimuli. CssS/CssR, a two-component system in Bacillus subtilis, is responsible for overcoming envelope stresses caused by heat shock and secretion overload. During stress, the sensor component CssS is auto-phosphorylated and transfers the phosphoryl group to the response regulator CssR. Phosphorylated CssR then directly regulates the transcription of genes required to counteract the stress. Here, the crystal structure of the DNA-binding domain of CssR, determined at 1.07 Å resolution, is reported. The structure shows that the DNA-binding domain of CssR harbors a winged helix-turn-helix motif that is conserved in the OmpR/PhoB subfamily of response regulators. Based on the crystal structure, the dimeric architecture of the full-length CssR and its DNA-binding mode were suggested.

The Burden Borne by Protein Methyltransferases: Rates and Equilibria of Non-enzymatic Methylation of Amino Acid Side Chains by SAM in Water.

SAM is a powerful methylating agent, with a methyl group transfer potential matching the phosphoryl group transfer potential of ATP. SAM-dependent N-methyltransferases have evolved to catalyze the modification of specific lysine residues in histones and transcription factors, in addition to generating epinephrine, N-methylnicotinamide, and a quaternary amine (betaine) that is used to maintain osmotic pressure in plants and halophilic bacteria. To assess the catalytic power of these enzymes and their potential susceptibility to transition state and multisubstrate analogue inhibitors, we determined the rates and positions of the equilibrium of methyl transfer from the trimethylsulfonium ion to model amines in the absence of a catalyst. Unlike the methyl group transfer potential of SAM, which becomes more negative with an increase in pH throughout the normal pH range, equilibrium constants for the hydrolytic demethylation of secondary, tertiary, and quaternary amines are found to be insensitive to a change in pH and resemble each other in magnitude, with an average ΔG value of approximately -0.7 kcal/mol at pH 7. Thus, each of the three steps in the mono-, di-, and trimethylation of lysine by SAM is accompanied by a change in free energy of -7.5 kcal/mol in a neutral solution. Arrhenius analysis of the uncatalyzed reactions shows that the unprotonated form of glycine attacks the trimethylsulfonium ion (TMS+) with second-order rates constant of 1.8 × 10-7 M-1 s-1 at 25 °C (ΔH⧧ = 22 kcal/mol, and TΔS⧧ = -6 kcal/mol). Comparable values are observed for the methylation of secondary and tertiary amines, with k25 values of 1.1 × 10-7 M-1 s-1 for sarcosine and 4.3 × 10-8 M-1 s-1 for dimethylglycine. The non-enzymatic methylations of imidazole and methionine by TMS+, benchmarks for the methylation of histidine and methionine residues by SETD3, exhibit k25 values of 3.3 × 10-9 and 1.2 × 10-9 M-1 s-1, respectively. Lysine methylation by SAM, although slow under physiological conditions (t1/2 = 7 weeks at 25 °C), is accelerated 1.1 × 1012 -fold at the active site of a SET domain methyltransferase.

Urea Salts with 1-Hydroxyethylidene Diphosphonic Acid

The reaction of urea with 1-hydroxyethylidene diphosphonic acid in the ratios of 1 : 1, 1 : 2, 1 : 3 was first studied. As a result of the reactions, the corresponding 1 : 2 or 2 : 1 salts were formed, which can exhibit biological activity. The synthesized compounds were characterized by atomic emission spectroscopy, IR and NMR spectroscopy. According to atomic emission analysis, an increase in the amount of urea from 3 moles or more per 1 mole of 1-hydroxyethylidene diphosphonic acid does not cause an increase in the urea content in the final products. According to NMR spectroscopy data, compounds in the formation of which phosphoryl groups of 1-hydroxyethylidene diphosphonic acid are involved are in dynamic equilibrium salt–free acid.

Second distinct conformation of the phosphohistidine loop in succinyl-CoA synthetase.

Succinyl-CoA synthetase (SCS) catalyzes a reversible reaction that is the only substrate-level phosphorylation in the citric acid cycle. One of the essential steps for the transfer of the phosphoryl group involves the movement of the phosphohistidine loop between active site I, where CoA, succinate and phosphate bind, and active site II, where the nucleotide binds. Here, the first crystal structure of SCS revealing the conformation of the phosphohistidine loop in site II of the porcine GTP-specific enzyme is presented. The phosphoryl transfer bridges a distance of 29 Å between the binding sites for phosphohistidine in site I and site II, so these crystal structures support the proposed mechanism of catalysis by SCS. In addition, a second succinate-binding site was discovered at the interface between the α- and β-subunits of SCS, and another magnesium ion was found that interacts with the side chains of Glu141β and Glu204β via water-mediated interactions. These glutamate residues interact with the active-site histidine residue when it is bound in site II.

Cellular and physiological approaches to evaluate the chelating effect of Chlorella on metal ion stressed lymphocytes.

Chlorella is a green alga consumed as dietary food supplement in pulverized form. In addition to its high nutritional value, it is reported as an excellent detoxifying agent. The pulverized Chlorella is partially soluble in water and insoluble portion has been reported for removal of mercury, cadmium and radioactive strontium from body. Chlorella contains a variety of metal-binding functional groups such as carboxyl, amino, phosphoryl, hydroxyl and carbonyl groups, which has high affinity towards various metal ions. The present study was envisaged to evaluate the chelating effect of water soluble fraction of Chlorella powder (AqCH) on metal ions. Fura-2 fluorescence ratio (F340/F380) was measured by fluorescence spectrometer (FS) after the exposure of chloride salt of metals viz., strontium, cobalt, barium, cesium, thallium and mercury to lymphocytes. Pretreatment of AqCH (0.1-20mg mL-1) was given to evaluate the attenuating effect on fura-2 fluorescence ratio induced by metal ions. The intracellular levels of these metal ions were analyzed by atomic absorption spectrophotometer (AAS) and fluorescence microscopy (FM). Pretreatment with AqCH significantly attenuated the metal induced fluorescence ratio in dose-dependent manner. The results of AAS and FM were found in coherence with fura-2 fluorescence ratio which emphasized that AqCH significantly prevented the metal ions internalization. The present study suggests AqCH chelates with these metal ions and prevents its interaction with cells thereby reducing the intracellular mobilization of Ca2+.

The heterogeneous substructure of casein micelles evidenced by SAXS and NMR in demineralized samples

The casein micelle (CM) have been described as a protein assembly held together by interactions between phosphoryl groups from the protein moieties, and several internal calcium phosphate nanoclusters (CCPs). While the presence of protein inhomogeneities at the small scale, sequestering the CCPs, has been widely accepted, the presence of medium scale inhomogeneities, the so-called “Hard” regions, and its relationship with the CCPs, has been object of debate. In the present work, solid state NMR and SAXS data have been combined to study the correlation between the removal of CCPs and the structural modification of the micelle. A « native » sample and three different demineralized ones; 5% (DM-05), 10% (DM-10), and 25% (DM-25) of calcium in relation with the «native», have been analyzed. NMR data show that the reduction in the total amount of calcium and phosphorous ions (−5%, −10% and −25% respectively) in the samples is not always equivalent to the loss of CCPs as measured by the decrease of the amount of colloidal 31P (−15 and −17% and −25% respectively) in the samples. NMR data also indicate, that demineralization induces the total depletion of some CCP while leaving the remaining cluster in a rather « native » like structure. SAXS data show a good correlation between the amount of 31P loss measured by NMR and the decreases in intensity for the SAXS spectral features associated with the nanoclusters. Finally, SAXS data show the demineralization induces a decrease in the amount of the larger inhomogeneities in the micelle (the so called “Hard” regions). However, this decrease is not directly correlated to the decrease in the amount of CCPs (as measured by SAXS and NMR) indicating that these “Hard” regions may be, at least partially, maintained by a large protein-protein interaction network. The data and results are discussed and compared with different structural models of casein micelle.

Influence of secondary metabolites on surface chemistry and metal adsorption of a devitalized lichen biomonitor.

Despite the broad use of lichens as biomonitors of airborne trace elements, the surface chemistry and metal adsorption parameters of these organisms are still poorly known. The current investigation is aimed at (i) quantifying the acid-base surface properties and the first-order physical-chemical parameters of Cu2+ and Zn2+ adsorption of devitalized Pseudevernia furfuracea, a lichen commonly used in biomonitoring of airborne trace elements, and (ii) comparing the results with those available for moss biomonitors. Equilibrium constants and metal-binding site concentrations were calculated with a thermodynamic model by taking into account the presence/absence of ancillary extracellular cell wall compounds, namely melanin and acetone-soluble lichen substances. An acid-base titration experiment performed in the pH range of 3-10 showed that melanised and non-melanised P.furfuracea samples have lower pHPZC (3.53-3.99) and higher metal-binding site concentrations (0.96-1.20mmolg-1) compared to that of the mosses investigated so far at the same experimental conditions. Melanin biosynthesis increased the content of carboxyl and phosphoryl groups and reduces that of amine/polyphenols. Cu2+ and Zn2+ adsorption was unaffected by the degree of melanisation while the removal of extracellular lichen substances slightly decreased Zn2+ adsorption. Although Cu2+ and Zn2+ adsorption parameters related to P.furfuracea surfaces were 3 times lower than in the mosses, lichen samples adsorbed the same amount of Cu2+ and 30% more Zn2+. The present study contributes in understanding the role of ancillary cell wall compounds in Cu2+ and Zn2+ adsorption in a model lichen. It also provides a first comparison between the surface physico-chemical characteristics of lichens and mosses frequently used as biomonitors of trace elements.

Structural insights into a new substrate binding mode of a histidine acid phosphatase from Legionella pneumophila

MapA is a histidine acid phosphatase (HAP) from Legionella pneumophila that catalyzes the hydroxylation of a phosphoryl group from phosphomonoesters by an active-site histidine. Several structures of HAPs, including MapA, in complex with the inhibitor tartrate have been solved and the substrate binding tunnel identified; however, the substrate recognition mechanism remains unknown. To gain insight into the mechanism of substrate recognition, the crystal structures of apo-MapA and the MapAD281A mutant in complex with 5′-AMP were solved at 2.2 and 2.6 Å resolution, respectively. The structure of the MapAD281A/5′-AMP complex reveals that the 5′-AMP fits fully into the substrate binding tunnel, with the 2′-hydroxyl group of the ribose moiety stabilized by Glu201 and the adenine moiety sandwiched between His205 and Phe237. This is the second structure of a HAP/AMP complex solved with 5′-AMP binding in a unique manner in the active site. The structure presents a new substrate recognition mechanism of HAPs.

A real-time 31P-NMR-based approach for the assessment of glycerol kinase catalyzed monophosphorylations

Phosphorous-NMR is scarcely employed to evaluate enzyme kinetics of kinase driven monophosphorylations, despite of being a powerful and reliable tool to undoubtedly detect the actual phosphoryl transfer to the targeted substrate. Another advantage is that an external supplementation source of the NMR active isotope is not required, since 31P is highly abundant in nature. Glycerol kinase (GlpK) from E. coli is an exemplary ATP-dependent kinase/phosphotransferase model to illustrate the value and usefulness of a 31P-NMR-based approach to assess the enzymatically driven monophosphorylation of glycerol. Moreover, the described approach offers an alternative to the indirect coupled glycerol kinase enzyme assays. Herein, we provided a real time 31P-NMR-based method customized for the direct assessment of the glycerol kinase enzyme activity.•Real-time detection for phosphoryl group dynamics in the GlpK driven reaction•Direct assessment of product formation (glycerol-monophosphate)•Parallel determination of cosubstrate (ATP) consumption and coproduct (ADP) generation•Method validation was performed via31P-NMR for each phosphorylated molecule involved in the reaction in order to assist in the molecular assignments

Organic photoredox catalytic α-C(sp3)-H phosphorylation of saturated aza-heterocycles.

A metal-free C(sp3)-H phosphorylation of saturated aza-heterocycles via the merger of organic photoredox and Brønsted acid catalyses was established under mild conditions. This protocol provided straightforward and economic access to a variety of valuable α-phosphoryl cyclic amines by using commercially available diarylphosphine oxide reagents. In addition, the D-A fluorescent molecule DCQ was used for the first time as a photocatalyst and exhibited an excellent photoredox catalytic efficiency in this transformation. A series of mechanistic experiments and DFT calculations demonstrated that this transformation underwent a sequential visible light photoredox catalytic oxidation/nucleophilic addition process.