Isovaleryl CoA dehydrogenase (IVDH) is a flavoprotein that introduce a trans-double bond between C2 and C3 of the isovaleryl CoA substrate, an intermediate in leucine catabolism pathway. Interrogation of the Paracoccus denitrificans Pd1222 genome has identified Pden_3633 gene as a candidate to encode for IVDH. In previous study by Rafid et al (under the publishing), this putative IVDH was expressed in E. coli and purified as N-terminal Strep-tagged protein. In current study, spectral properties of the purified IVDH were conducted and the results showed that the enzyme was obtained as an apoprotein. For this reason, IVDH has been reconstituted by incubation with flavin adenine dinucleotide (FAD) and the experiment showed that the ratio 1: 20% (IVDH: FAD molar excess) was achieved fully reconstitution. Furthermore, kinetic parameters of the reconstituted IVDH were studied and the enzyme exhibited a specific activity for isovaleryl-CoA substrate while Vmax and KM were estimated to be 600 mU mg-1 and 7.13 μM respectively. Finally, gel filtration by using HiLoad 16/60 Superdex 200 column was performed to investigate the quaternary structure of the recombinant IVDH. An apparent molecular weight of 171640 Da was determined.
In Paracoccus denitrificans Pd1222 bacterium, Pden_3633 encoding gene has been nominated to encode for Isovaleryl CoA dehydrogenase (IVDH) [1], the enzyme which involve in leucine catabolism pathway. In this study, this putative IVDH was investigated. IVDH encoding gene from P. denitrificans Pd1222 in addition to desired features for cloning, expression and purification have been designed and synthesized. The synthetic coding sequence was expressed in Escherichia coli. The enzyme was purified as a Strep-Tagged protein with a total protein 220.5 mg. An apparent molecular weight of 42.9 kDa was determined on SDS gel. Amino acid alignment showed a very high similarity (91-96%) with corresponding IVDH from several other Paracoccus species. A
... Show MoreAlbumin is the most abundant protein in blood plasma, serves as a circulating depot for endogenous and exogenous (e.g. drugs) compounds due to its ligand binding properties, this work aim to get information about the binding of Amoxicillin (antibiotics) with albumin, and the influence of the solvent polarity and ionic strength on it by using UV -vis spectrophotometric measurements in phosphate buffer of pH7.4 and three different temperature (290, 300, 310) K. The UV absorption shows a change and a shift in the absorbency and a shift in albumin and amoxicillin peaks, the two changes are indicative of complex formation. The stoichiometry of the interaction were calculated by the method of continuous variations which was1:1at pH 7.4.The equ
... Show MoreThe influence of Diethyl phthalate (DEP) on the optical characteristics of polystyrene solutions in the range between 200 to 400 nm at solvents of different polarities; chloroform, cyclohexane, dichloromethane, and tetrahydrofuran have been recorded. The experimental results showed that the behavior of the photophysical processes of polymer solutions depends on the nature of its environment. The intensity of the absorption and fluorescence spectra depends on the interactions between solvent-solute molecules. The experimental results indicate that the maximum most absorbance bands occur around 262 nm, which depends on the concentration of the quencher. The results did not determine any change in the positions of the most absorption bands.
... Show MoreThe spectroscopic properties, potential energy curve, dipole moments, total charge density, Electrostatic potential as well as the thermodynamic properties of selenium diatomic halides have been studied using code Mopac.7.21 and hyperchem, semi-empirical molecular orbital of MNDO-method (modified neglected of differential overlap) of parameterization PM3 involving quantum mechanical semi-empirical Hamiltonian. The relevant molecular parameters like interatomic distance, bond angle, dihedral angle and net charge were also calculated.
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In this paper, a construction microwave induced plasma jet(MIPJ) system was used to produce a non-thermal plasma jet at atmospheric pressure, at standard frequency of 2.45 GHz and microwave power of 800 W. The working gas Argon (Ar) was supplied to flow through the torch with adjustable flow rate using flow meter regulator. The influence of the MIPJ parameters such as applied voltage and argon gas flow rate on macroscopic microwave plasma parameters were studied. The macroscopic parameters results show increasing of microwave plasma jet length with increasing of applied voltage, argon gas flow rate where the plasma jet length exceed 12 cm as maximum value. While the increasing of argon gas flow rate will cause increasing into the ar
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At atmospheric pressure and at a frequency of 9.1 kHz, a constructed magnetically stabilized tornado gliding arc discharge (MSGAD) system was utilized in this study to generate a non-thermal plasma with an alternating voltage source from 2,4,6,8 to 10 kV. Argon gas was used to generate the arc plasma with an adjustable flow rate using a flow meter regulator to stabilize the gas flow rate to 2 L/min. A gliding plasma discharge is achieved by a magnetic field for the purpose of a planned investigation. The influence of the magnetically stabilized tornado gliding arc discharge parameters such as magnetic field and applied voltage on microscopic tornado plasma parameters was studied. The electron temperature1was measured using a Boltzmann plot
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Background:
Acute leukemias are clonal neoplastic proliferations of immature cells of the hemopoietic system. They are divided into acute myeloid leukemia (AML), acute
lymphoblastic leukemia (ALL) and acute undifferentiated leukemia (AUL). LDH has been suggested as a possible non-specific tumor marker for many years, and total serum LDH is
frequently elevated in neoplastic diseases. The aims of the study are to evaluate the significance of increased serum LDH levels in patients with acute leukemia and to
determine the importance of serum LDH level in the follow up and assessment of treatment responses.
Patients, Materials and Methods:
This study was conducted at Baghdad Teaching Hospital in Medical C
The research is dealing with the absorption and fluorescence spectra for the hybrid of an Epoxy Resin doped with organic dye Rhodamine (R6G) of different concentrations (5*10-6, 5*10-5, 1*10-5, 1*10-4, 5*10-4) Mol/ℓ at room temperature. The Quantum efficiency Qfm, the rate of fluorescence emission Kfm (s-1), the non-radiative lifetime τfm (s), fluorescence lifetime τf and the Stokes shift were calculated. Also the energy gap (Eg) for each dye concentration was evaluated. The results showed that the maximum quantum effi
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