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1.
The kinetics of the oxidation of tris(2,2′-bipyridyl)iron(II) and tris(1,10-phenanthroline)iron(II) complexes ([Fe(LL)3]2+, LL = bipy, phen) by nitropentacyanocobaltate(III) complex [Co(CN)5NO2]3? was investigated in acidic aqueous solutions at ionic strength of I = 0.1 mol dm?3 (HCl/NaCl). The reactions were carried out at fixed acid concentration ([H+] = 0.01 mol dm?3) and the temperature maintained at 35.0 ± 0.1 °C. Spectroscopic evidence is presented for the protonated oxidant. Protonation constants of 360.43 and 563.82 dm3 mol?1 were obtained for the monoprotonated and diprotonated Co(III) complexes respectively. Electron transfer rates were generally faster for [Fe(bipy)3]2+ than [Fe(phen)3]2+. The redox complexes formed ion-pairs with the oxidant with increasing concentration of the oxidant over that of the reductant. Ion-pair constants for these reaction were 160.31 and 131.9 dm3 mol?1 for [Fe(bipy)3]2+ and [Fe(phen)3]2+, respectively. The activation parameters measured for these systems have values as follows: ?H ≠ (kJ K?1 mol?1) = +113.4 ± 0.4 and +119 ± 0.3; ?S ≠ (J K?1) = +107.6 ± 1.3 and 125.0 ± 1.6; ?G ≠ (kJ K?1) = +81 ± 0.4 and +82.4 ± 0.4; and E a (kJ mol?1) = 115.9 ± 0.5 and 122.3 ± 0.6 for LL = bipy and phen, respectively. Effect of added anions (Cl?, $ {\text{SO}}_{4}^{2 - } $ and $ {\text{ClO}}_{4}^{ - } $ ) on the systems showed decrease in the electron transfer rate constant. An outer-sphere mechanism is proposed for the reaction. 相似文献
2.
E. Makrlík P. Toman P. Vaňura 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1119-1122
From extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium Sr2+(aq) + 2A?(aq) +1(nb) ? 1·Sr2+(nb) + 2A?(nb) taking place in the two-phase water–nitrobenzene system (A? = picrate, 1 = beauvericin; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log K ex(1·Sr2+,2A?) = ?0.6 ± 0.1. Further, the stability constant of the 1·Sr2+ complex in nitrobenzene saturated with water was calculated for a temperature of 25 °C: log β nb(1·Sr2+) = 8.5 ± 0.1. Finally, by using quantum-mechanical DFT calculations, the most probable structure of the resulting cationic complex 1·Sr2+ was derived. 相似文献
3.
The hydrolytic species of lanthanide ions, La3+ and Sm3+, in water at I = 0.1 mol·dm?3 KCl ionic strength and temperatures of 298.15, 310.15 and 318.15 K were investigated by potentiometry. The hydrolytic species were modeled by the HySS simulation program. From the results, the hydrolytic species of each metal ion at different temperatures were calculated using the program HYPERQUAD2013. The hydrolysis constants (log10 β) of [La(OH)]2+ and La(OH)3 were calculated as ?8.52 ± 0.46, ?26.84 ± 0.48, and log10 β values of [Sm(OH)]2+, [Sm(OH)2]+, Sm(OH)3 were calculated as ?7.11 ± 0.21, ?15.84 ± 0.25 and ?23.44 ± 0.52 in aqueous media at 298.15 K, respectively. The dependence of the hydrolysis constants on the temperature allowed us to calculate the enthalpy, entropy, and Gibbs energy of hydrolysis values of each species. 相似文献
4.
Recycling of NADP+ using immobilized wholeEscherichia coli cells as source of respiratory chain, glucose-6-phosphate, and soluble yeast glucose-6-phosphate dehydrogenase (1.1.1.49) is described. NADP+ was recycled more than 10-fold. We demonstrated NADPH respiration at pH 5.8 inE. coli membrane vesicles. The respiratory chain was involved most probably in NADPH oxidation.
- The respiratory activity is localized at the level of the inner bacterial membrane. The active site for NADPH facing the cytoplasm.
- NADPH respiration is inhibited by 10 mM cyanide, similar to the conditions of inhibition of NADH respiration.
- NADPH dehydrogenase activity seems to be the limiting step of the respiratory chain:K M for NADPH respiration and NADPH dehydrogenase activity are similar. The pH optima for these two activities are also comparable (around pH 5.8). Furthermore, the following properties are rather in favor of a common NADH dehydrogenase and NADPH dehydrogenase activity (1.6.99.2).
5.
I. V. Mironov 《Russian Journal of Inorganic Chemistry》2007,52(6):960-962
The substitution equilibria AuCl 2 ? + iNH 4 + = Au(NH3)iCl2 ? i + iCl? + iH+, β i * . were studied pH-metrically at 25°C and I = 1 mol/L (NaCl) in aqueous solution. It was found that logβ 1 * = ?5.10±0.15 and logβ 2 * = ?10.25±0.10. For equilibrium AuNH3Clsolid = AuNH3Cl, log K s = ?3.1±0.3. Taking into account the protonation constants of ammonia (log K H = 9.40), the obtained results show that for equilibria AuCl 2 ? + iNH3 = Au(NH3)iCl2 ? i + iCl?, logβ1 = 4.3±0.2, and logβ2 = 8.55±0.15. The standard potentials E 0 1/0 of AuNH3Cl0 and Au(NH3) 2 + species are equal to 0.90±0.02 and 0.64±0.01 V, respectively. 相似文献
6.
Hee-Chul Yang Min-Woo Lee Ho-Sang Hwang Jei-Kwon Moon Dong-Yong Chung 《Journal of Thermal Analysis and Calorimetry》2014,118(2):1073-1083
Kinetics of two successive thermal decomposition reaction steps of cationic ion exchange resins and oxidation of the first thermal decomposition residue were investigated using a non-isothermal thermogravimetric analysis. Reaction mechanisms and kinetic parameters for three different reaction steps, which were identified from a FTIR gas analysis, were established from an analysis of TG analysis data using an isoconversional method and a master-plot method. Primary thermal dissociation of SO3H+ from divinylbenzene copolymer was well described by an Avrami–Erofeev type reaction (n = 2, g(α) = [?ln(1 ? α)]1/2]), and its activation energy was determined to be 46.8 ± 2.8 kJ mol?1. Thermal decomposition of remaining polymeric materials at temperatures above 400 °C was described by one-dimensional diffusion (g(α) = α 2), and its activation energy was determined to be 49.1 ± 3.1 kJ mol?1. The oxidation of remaining polymeric materials after thermal dissociation of SO3H+ was described by a phase boundary reaction (contracting volume, g(α) = 1?(1 ? α)1/3). The activation energy and the order of oxygen power dependency were determined to be 101.3 ± 13.4 and 1.05 ± 0.17 kJ mol?1, respectively. 相似文献
7.
E. Makrlík P. Vaňura S. Böhm P. Ruzza 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(3):1291-1294
By using extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium Sr2+(aq) + 2A?(aq) + 1(nb) ? 1·Sr2+(nb) + 2A?(nb) occurring in the two-phase water–nitrobenzene system (A? = picrate, 1 = antamanide; aq = aqueous phase, nb = nitrobenzene phase) was determined as log K ex (1·Sr2+, 2A?) = ?0.3 ± 0.1. Further, the stability constant of the 1·Sr2+ complex in nitrobenzene saturated with water was calculated for a temperature of 25 °C: log β nb (1·Sr2+) = 8.8 ± 0.1. Finally, applying quantum mechanical density functional level of theory calculations, the most probable structure of the cationic complex species 1·Sr2+ was derived. In the resulting complex, the “central” cation Sr2+ is bound by six bond interactions to the corresponding six oxygen atoms of the parent ligand 1. The interaction energy of the considered 1·Sr2+ complex was found to be ?1,114.9 kJ/mol, confirming the formation of this cationic species as well. 相似文献
8.
E. A. Walters J. R. Grover M. G. White 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1986,4(1):103-110
The dissociation energy of the C2H4 · HCl van der Waals complex was determined to be 3.18±0.73 kcal mol?1 by a dissociative photoionization technique. C2H4 · HCl was produced by free expansion of a 1:4 mixture of C2H4 in HCl and the clusters were ionized with tunable synchrotron radiation. The photoionization efficiency function of (C2H4 · HCl)+ from C2H4 · HCl was determined between 600 and 1,300 Å and the onset for (C2H4 · HCl)+ was established as 1,163±2 Å = 10.66±0.02 eV; these values give ΔH f 0 (C2H4 · HCl) = ?10.7±0.7 kcal mol?1 and ΔH f 0 (C2H4·HCl+)=235.1±0.9 kcal mol?1. A complex ion dissociation energyD 0(C2H4 · HCl+) = ?0.3±0.9 kcal mol?1 was calculated from the results. The major features on the PIE curve for C2H4 · HCl+ can be analyzed in terms of the known energetic features of C2H 4 + and HCl. An extended energy diagram for the C2H4 + HCl system is presented. 相似文献
9.
Andreas D. Zuberbühler 《Helvetica chimica acta》1976,59(5):1448-1459
The complexation of 1-methyl-2-hydroxymethyl-imidazole (L) with Cu(I) and Cu(II) has been studied in aqueous acetonitrile (AN). Cu(I) forms three complexes, Cu(AN)L+, CuL2+, and Cu(AN)H?1L, with stability constants logK(Cu(AN)+ + L ? Cu(AN)L+) = 4.60 ± 0.02, logβ2 = 11.31 ± 0.04, and logK(Cu(AN)H?1L+H+ ? Cu(AN)L+) = 10.43 ± 0.08 in 0.15M AN. The main species for Cu(II) are CuL2+, CuH?1L+, CuH?1L2+, and CuH?2L2. The autoxidation of CuL2+ was followed with an oxygen sensor and spectrophotometrically. Competition between the formation of superoxide in a one-electron reduction of O2 and a path leading to H2O2 via binuclear (CuL2)2O was inferred from the rate law with ka = (2.31 ± 0.12) · 104M ?2S ?1, kb = (1.0 ± 0.2) · 103M ?1, kc = (2.85 ± 0.07) · 102M ?2S ?1, kd = 3.89 ± 0.14M ?1S ?1, ke = 0.112 ± 0.004, kf = (2.06 ± 0.24) · 10?10M S ?1, kg = (1.35 ± 0.07) · 10?7 S ?1, and kh = (6.8 ± 1.4) · 10?7M ?1 S ?1. 相似文献
10.
Feng Xue Zhi-Qiang Liu Nan-Wei Wan Yu-Guo Zheng 《Applied biochemistry and biotechnology》2014,174(1):352-364
A novel halohydrin dehalogenase (HHDH), catalyzing the transformation of 1,3-dichloro-2-propanol (1,3-DCP) to epichlorohydrin (ECH), was purified from Agromyces mediolanus ZJB120203. The molecular mass of the enzyme was estimated to be 28 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). A 735-bp nucleotide fragment was obtained based on the N-terminal and internal amino acid sequences of the purified HHDH. The gene codes a protein sequence with 244 amino acid residues, and the protein sequence shows high similarity to Hhe AAD2 (HHDH from Arthrobacter sp. AD2), defined as Hhe AAm, which is the seventh reported HHDH. Expression of Hhe AAm was carried out in Escherichia coli and purification was performed by nickel-affinity chromatography. The recombinant HheAAm possessed an optimal pH of 8.5 and an optimal temperature of 50 °C and manifested a K m of 4.58 mM and a V max of 3.84 μmol/min/mg. The activity of Hhe AAm was not significantly affected by metal ions such as Zn2+, Ca2+, Cu2+, and EDTA, but was strongly inhibited by Hg2+ and Ag+. In particular, the Hhe AAm exhibits an enantioselectivity for the conversion of prochiral 1,3-DCP to (S)-ECH. The applications of the Hhe AAm as a catalyst for asymmetric synthesis are promising. 相似文献
11.
The time evolutions ψ+(t) and ψ?(t) of dihydrides' near degenerate local modes with + and ? symmetry may be evaluated by Fast Fourier Transform (FFT) propagation of a single bond-adapted wavefunction ψ a = 2?1/2 (ψ+?ψ?). This economic technique is demonstrated by model simulations of fast dissociations of highly excited local stretches of H2O. 相似文献
12.
The solubility of carefully characterized magnetite, Fe3O4, in dilute aqueous solutions saturated with H2 has been measured at temperatures from 100 to 300°C in a flow apparatus. Solution compositions included either HCl or NaOH molalities of up to 1 and 40 mmole-kg?1, respectively, and H2 molalities of 0.0779, 0.779, and 8.57 mmole-kg?1. The dependence of the equilibrium solubility on the pH and reduction potential were fitted to a scheme of soluble ferrous and ferric species consisting of Fe2+, FeOH+, Fe(OH)2, Fe(OH) 3 ? , Fe(OH)3, and Fe(OH) 4 ? . Solubility products from the fit, corresponding to the reactions $$\tfrac{1}{3}Fe_3 O_4 + (2 - b)H^ + + \tfrac{1}{3}H_2 \rightleftharpoons Fe(OH)_b^{2 - b} + (4/3 - b)H_2 O$$ and $$\tfrac{1}{3}Fe_3 O_4 + (3 - b)H^ + \rightleftharpoons Fe(OH)_b^{3 - b} + \tfrac{1}{6}H_2 + (4/3 - b)H_2 O$$ were used to derive thermodynamic constants for each species. The extrapolared value for the Gibbs energy of formation of Fe2+ at 25°C is ?88.92±2.0 kJ-mole?1, consistent with standard reduction potentials in the range Eo(Fe2+)=?0.47±0.01 V. The temperature coefficient of the equilibrium Fe molality, (?m(Fe, sat.)/?T)m(H2).m(NaOH), changes from negative to positive as the NaOH molality is increased to the point where Fe(OH) 3 ? and Fe(OH) 4 ? predominate. 相似文献
13.
I. V. Mironov 《Russian Journal of Inorganic Chemistry》2007,52(5):791-792
The stepwise substitution equilibrium AuCl 2 ? +iX?=AuCl2?i X i ? +iCl?, βi, where X? is the glycinate ion (H2N-CH2-COO?), i = 1 or 2, at 25°C in an aqueous solution with I = 1.0 mol/L (NaCl) has been studied pH-metrically. The corresponding constants are logβ1 = 3.60 ± 0.10, and logβ2 = 6.2 ± 0.2. 相似文献
14.
W. Simon A. J. Yencha M. -W. Ruf H. Hotop 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,8(1):71-84
Using a beam apparatus, we have measured the HCl+ (A,v′→X,v″) fluorescence spectra of HCl+ (A,v′) ions formed in HeI (58.4 nm), and NeI (73.6 nm) photoionization and, for the first time, in He (23 S) Penning ionization under single collision conditions with a wavelength bandwidth around 1 nm. In addition, we have studied Ne (3s 3 P 2, 0) Penning ionization of HCl at three different collision energies. The procedure and the problems in extracting HCl+ (A,v′) vibrational populations from the data are discussed in some detail. Thedirect comparison of photoionization and Penning ionization data allows definitive conclusions to be drawn on the question whether final state interactions in the Penning reaction change the “nascent” vibrational population (determined by electron spectrometry); for He (23 S)+HCl, such changes are shown to be absent within the experimental uncertainty (<±10%). For Ne (3s 3 P 2, 0)+HCl, the HCl+ (A,v′=0, 1) populations are also found to be close to those measured by electron spectrometry and essentially independent of collision energy in the range 34–96 meV. From measurements of the fluorescence intensity as a function of HCl density, we have evidence for a fast loss of HCl+ (A,v′) ions in collisions with HCl (rate constant around 5·10?9 cm3s?1). 相似文献
15.
Wen-jie Liang Yi-ping Chen Feng-ying Zheng Shun-Xing Li 《Mikrochimica acta》2014,181(13-14):1513-1519
Nanometer-sized titanium dioxide (nano-TiO2) is shown to be a viable material for the preconcentration of Alizarin Violet (AV, a common dye and biological stain). In the preconcentration step, a 5-ring cyclic ester is formed between the ortho-dihydroxy groups of AV and two hydroxy groups of the titanic acid on the surface of the nano-TiO2. Under optimized conditions, the adsorption capacity of nano-TiO2 is?~?20 μg?·?mg?1, the adsorption efficiency is 98 %. The adsorbed AV can be eluted with 5 mL of 5 mol?·?L?1 5-sulfosalicylic acid with an elution efficiency of more than 91.8 %. The preconcentration factor is 50 in case of 250 mL samples. Spectrophotometric determination of AV in the eluate gives a linear calibration plot in the range between 18.8 μg?·?L?1 and 10 mg?·?L?1 and a detection limit (3 s; for n?=?11) of 18.8 μg?·?L?1. The method is simple and fast. It was successfully applied to the analysis of AV in spiked natural waters, and recoveries were found to range between 94.2 and 97.3 %.
Nanometer-sized titanium dioxide is a viable material for the preconcentration of Alizarin Violet (AV), before its spectrophotometrical determination. The method is simple and fast. It was successfully applied to the analysis of AV in spiked natural waters, and recoveries were found to range between 94.2 and 97.3 %. 相似文献
16.
Edgardo Valenzuela-Reyes Sergio Casas-Flores Isabel Isordia-Jasso Sonia Arriaga 《Applied biochemistry and biotechnology》2014,174(2):832-844
In this work, several conditions of pH and inlet load (IL) were applied to a scale laboratory biofilter treating n-hexane vapors during 143 days. During the first 79 days of operation (period 1, P1), the system was fed with neutral pH mineral medium (MM) and the IL was progressively decreased from 177 to 16 g m?3 h?1. A maximum elimination capacity (EC) of 30 g m?3 h?1 was obtained at an IL of 176.9?±?9.8 g m?3 h?1. During the following 64 days (period 2, P2), acidic conditions were induced by feeding the biofilter with acidic buffer solution and pH 4 MM in order to evaluate the effect of bacterial community changes on EC. Within the acidic period, a maximum EC of 54 g m?3 h?1 (IL 132.3?±?13 g m?3 h?1) was achieved. Sequence analysis of 16S rDNA genes amplified from the consortium revealed the presence of Sphingobacteria, Actinobacteria, and α-, β- and γ-Proteobacteria. An Actinobacteria of the Mycobacterium genus had presence throughout the whole experiment of biofiltration showing resistance to fluctuating pH and IL conditions. Batch tests confirm the bacterial predominance and a negligible contribution of fungi in the degradation of n-hexane. 相似文献
17.
Luana Parras Meleiro Ana Lucia Ribeiro Latorre Zimbardi Flavio Henrique Moreira Souza Douglas Chodi Masui Tony Marcio Silva João Atilio Jorge Rosa Prazeres Melo Furriel 《Applied biochemistry and biotechnology》2014,173(2):391-408
Humicola insolens produced a new β-glucosidase (BglHi2) under solid-state fermentation. The purified enzyme showed apparent molecular masses of 116 kDa (sodium dodecyl sulfate–polyacrylamide gel electrophoresis) and 404 kDa (gel-filtration), suggesting that it is a homotetramer. Mass spectrometry analysis showed amino acid sequence similarity with a β-glucosidase from Chaetomium thermophilum. Optima of pH and temperature were 5.0 and 65 °C, respectively, and the enzyme was stable for 60 min at 50 °C, maintaining 71 % residual activity after 60 min at 55 °C. BglHi2 hydrolyzed p-nitrophenyl-β-d-glucopyranoside and cellobiose. Cellobiose hydrolysis occurred with high apparent affinity (K M?=?0.24?±?0.01 mmol L?1) and catalytic efficiency (k cat/K M?=?1,304.92?±?53.32 L mmol?1 s?1). The activity was insensitive to Fe+3, Cr+2, Mn+2, Co+2, and Ni2+, and 50–60 % residual activities were retained in the presence of Pb2+, Hg2+, and Cu2+. Mixtures of pure BglHi2 or H. insolens crude extract (CE) with crude extracts from Trichoderma reesei fully hydrolyzed Whatman no. 1 paper. Mixtures of H. insolens CE with T. reesei CE or Celluclast 1.5 L fully hydrolyzed untreated printed office paper, napkin, and magazine papers after 24–48 h, and untreated cardboard was hydrolyzed by a H. insolens CE/T. reesei CE mixture with 100 % glucose yield. Data revealed the good potential of BglHi2 for the hydrolysis of waste papers, promising feedstocks for cellulosic ethanol production. 相似文献
18.
High-performance affinity chromatography (HPAC) was utilized to examine the binding of very low density lipoprotein (VLDL) with drugs, using R/S-propranolol as a model. These studies indicated that two mechanisms existed for the binding of R- and S-propranolol with VLDL. The first mechanism involved non-saturable partitioning of these drugs with VLDL, which probably occurred with the lipoprotein’s non-polar core. This partitioning was described by overall affinity constants of 1.2 (±0.3)?×?106 M?1 for R-propranolol and 2.4 (±0.6)?×?106 M?1 for S-propranolol at pH 7.4 and 37 °C. The second mechanism occurred through saturable binding by these drugs at fixed sites on VLDL, such as represented by apolipoproteins on the surface of the lipoprotein. The association equilibrium constants for this saturable binding at 37 °C were 7.0 (±2.3)?×?104 M?1 for R-propranolol and 9.6 (±2.2)?×?104 M?1 for S-propranolol. Comparable results were obtained at 20 and 27 °C for the propranolol enantiomers. This work provided fundamental information on the processes involved in the binding of R- and S-propranolol to VLDL, while also illustrating how HPAC can be used to evaluate relatively complex interactions between agents such as VLDL and drugs or other solutes. 相似文献
19.
G. Bhuvanalogini N. Murugananthem V. Shobana A. Subramania 《Journal of Solid State Electrochemistry》2014,18(9):2387-2392
We prepared LiNi0.4Co0.6O2 nanofibers by electrospinning at the calcination temperature of 450 °C for 6 h. The prepared LiNi0.4Co0.6O2 nanofibers was characterized by thermal, X-ray diffraction, and Fourier transform infrared (FTIR) studies. The morphology of LiNi0.4Co0.6O2 nanofibers was characterized by scanning electron microscopy studies. The asymmetric supercapacitor was fabricated using LiNi0.4Co0.6O2 nanofibers as positive electrode and activated carbon (AC) as negative electrode and a porous polypropylene separator in 1 M LiPF6–ethylene carbonate/dimethyl carbonate (LiPF6–EC:DMC) (1:1?v/v) as electrolyte. Cyclic voltammetry studies were then carried out in the potential range of 0 to 3.0 V at different scan rates which exhibited the highest specific capacitance of 72.9 F g?1. The electrochemical impedance measurements were carried out to find the charge transfer resistance and specific capacitance of the cell, and they were found to be 5.05 Ω and 67.4 F g?1, respectively. Finally, the charge–discharge studies were carried out at a current density of 1 mA cm?2 to find out the discharge-specific capacitance, energy density, and power density of the capacitor cell, and they were found to be 70.9 F g?1, 180.2 Wh kg?1, and 248.0 W kg?1, respectively. 相似文献
20.
Xue Li Peng Wang Yadong Ge Wen Wang Abdulla Abbas Guoping Zhu 《Applied biochemistry and biotechnology》2013,171(2):403-416
NADP+-dependent isocitrate dehydrogenase from Yarrowia lipolytica CLIB122 (YlIDP) was overexpressed and purified. The molecular mass of YlIDP was estimated to be about 81.3 kDa, suggesting its homodimeric structure in solution. YlIDP was divalent cation dependent and Mg2+ was found to be the most favorable cofactor. The purified recombinant YlIDP displayed maximal activity at 55 °C and its optimal pH for catalysis was found to be around 8.5. Heat inactivation studies revealed that the recombinant YlIDP was stable below 45 °C, but its activity dropped quickly above this temperature. YlIDP was absolutely dependent on NADP+ and no NAD-dependent activity could be detected. The K m values displayed for NADP+ and isocitrate were 59 and 31 μM (Mg2+), 120 μM and 58 μM (Mn2+), respectively. Mutant enzymes were constructed to tentatively alter the coenzyme specificity of YlIDP. The K m values for NADP+ of R322D mutant was 2,410 μM, being about 41-fold higher than that of wild type enzyme. NAD+-dependent activity was detected for R322D mutant and the K m and k cat values for NAD+ were 47,000 μM and 0.38 s?1, respectively. Although the R322D mutant showed low activity with NAD+, it revealed the feasibility of engineering an eukaryotic IDP to a NAD+-dependent one. 相似文献