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Nattokinase is a single polypeptide chain composed of 275 amino acids (molecular weight 27 724) which displays strong fibrinolytic activity. Moreover, it can activate other fibrinolytic enzymes such as pro-urokinase and tissue plasminogen activator. In the present study, native nattokinase from Bacillus subtilis natto was purified using gel-filtration chromatography and crystallized to give needle-like crystals which could be used for X-ray diffraction experiments. The crystals belonged to space group C2, with unit-cell parameters a = 74.3, b = 49.9, c = 56.3 A, β = 95.2°. Diffraction images were processed to a resolution of 1.74 A with an Rmerge of 5.2% (15.3% in the highest resolution shell) and a completeness of 69.8% (30.0% in the highest resolution shell). This study reports the first X-ray diffraction analysis of nattokinase.

There is an increasing need for patients affected by cerebrovascular diseases to receive continuous and proper rehabilitation support in his/her home. To this end, many robotic rehabilitation support devices for finger therapy have been proposed. However, there has been no consideration for treatment of “fingertips” with these finger therapy support devices. An active touch uses fingertip to discriminate the object in touch. It uses both sensational and motor control nerve systems. Therefore, there is a possibility that the active touch will improve the activities of a spinal cord, and therefore contribute to improve the effectiveness of a finger rehabilitation. A new robotic device that includes the active touch task with finger movements will provide an ideal home rehabilitation device. In this paper, we show that an active touch for pattern discrimination task will improve the activities of spinal cord. The measurement was performed by using F-waves and M-waves given by the evoked-EMG signals applied to healthy subjects. By the experiments, it was shown that the activity is significantly high for the cases of performing active touch tasks. We would like to utilize the results of this study for an exploitation of a robotic finger functional treatment machine used at home., doi: 10.1109/BMEiCON.2015.7399527

Indirect enzyme-linked immunosorbent assays (ELISAs) have been applied to detect immunoglobulin Y antibodies to different serotypes of Salmonella in the yolks of chicken eggs with heat-extracted antigens of Salmonella enterica serotypes Agona (SA), Cerro (SC), Enteritidis (SE), Montevideo (SM), and Putten (SP). The egg yolk samples examined were classified as positive if their ELISA absorbance values exceeded the value for eggs from specific-pathogen-free flocks by more than two standard deviations. Of 30 egg yolk samples from three flocks vaccinated with a killed SE vaccine, 29 were antibody positive by the ELISA assay for the SE antigen. Four to 29 of the 29 yolk samples showed positive results for the other serovars, although the absorbance values for SE were higher than those obtained for the other serotypes in each of the yolk samples. All 30 yolks from three flocks that were not administered any SE vaccines were found to be antibody negative for SE, and two samples were determined to be positive for SC. Thirty-nine or 40 eggs were obtained from each of four layer flocks in a commercial egg production farm where the laying houses were naturally contaminated with SA, SC, SM, SP, Salmonella serovar Infantis (SI), and untypeable strains. The ELISA absorbance values for SM in the egg yolks obtained from the two flocks molted through feed withdrawal when the birds restarted laying were significantly (P < 0.05) higher than those observed in the yolks obtained before the molt. In egg yolks from the two other flocks that were molted through a wheat bran diet, there was no significant difference between the absorbance values before and after the molt. The observations in the present study provide further evidence to suggest that a molt initiated through the administration of a wheat bran diet can reduce the risk for Salmonella problems in a commercial egg-producing setting.

N 2 O reductase activity in soybean nodules formed with Bradyrhizobium japonicum was evaluated from N 2 O uptake and conversion of 15 N-N 2 O into 15 N-N 2 . Free-living cells of USDA110 showed N 2 O reductase activity, whereas a nosZ mutant did not. Complementation of the nosZ mutant with two cosmids containing the nosRZDFYLX genes of B. japonicum USDA110 restored the N 2 O reductase activity. When detached soybean nodules formed with USDA110 were fed with 15 N-N 2 O, they rapidly emitted 15 N-N 2 outside the nodules at a ratio of 98.5% of 15 N-N 2 O uptake, but nodules inoculated with the nosZ mutant did not. Surprisingly, N 2 O uptake by soybean roots nodulated with USDA110 was observed even in ambient air containing a low concentration of N 2 O (0.34 ppm). These results indicate that the conversion of N 2 O to N 2 depends exclusively on the respiratory N 2 O reductase and that soybean roots nodulated with B. japonicum carrying the nos genes are able to remove very low concentrations of N 2 O.

A major histcompatibility complex (MHC) class I protein H-2K(b) was expressed in a large scale as a fusion protein with thioredoxin and hexahistidine at the N-terminus to analyze the interaction with the antigen peptide SIYRYYGL. NMR spectra of the peptide in the mixture solution with the protein showed very broad signals, indicating the obviously clear existence of the dynamic interaction between the class I protein and the antigen peptide. The interaction of the protein and peptide was discussed as well as the surrounding atmosphere of the peptide in the complex.

In 13C NMR spectra, four signals of two trans and two cis conformers in caprylolactam were found in a mixed solvent of water and methanol. NMR line broadenings and coalescent phenomena in two confo...

Various conformational states of polypeptide chains were investigated by synchrotron small-angle X-ray scattering (SAXS). SAXS patterns of proteins and model polypeptides in globular states (native and "molten globule") and in non-globular states (unfolded protein as well as randomly coiled, partially alpha-helical and partially beta-structural synthetic polypeptides) were analyzed in terms of Guinier and Kratky plots. Large differences in the SAXS pattern have been found between globular and non-globular conformations of the polypeptide chains, and they have been interpreted in terms of differences in the shape and size of the globular and non-globular scatterers with the same molecular mass. The equilibrium and time-resolved unfolding curves of bovine carbonic anhydrase and yeast phosphoglycerate kinase were monitored by integrated SAXS intensity, and were found to be coincident with the curves measured by other physicochemical techniques, such as tryptophan fluorescence and peptide circular dichroism spectra. The intermolecular association of the protein "molten globule"-like intermediates accumulated during the guanidine hydrochloride-induced unfolding of bovine carbonic anhydrase has been investigated by various SAXS parameters. It has been shown that the integrated SAXS intensity is much less sensitive to the protein intermolecular association than the zero angle intensity and the radius of gyration. We propose the integrated SAXS intensity as a global parameter which is particularly appropriate for fast kinetic studies of protein coil to globule transitions. Time-resolved refolding curves of the above proteins were monitored by the integrated SAXS intensity to investigate the globularization process in protein folding. Two fast kinetic processes for bovine carbonic anhydrase and two fast (each within two seconds) as well as two slow (within 500 seconds) kinetic processes for yeast phosphoglycerate kinase have been recorded. The kinetic processes reflect both protein intramolecular globularization and its intermolecular association.

The refolding kinetics of horse cyanometmyoglobin induced by concentration jump of urea was investigated by five optical probe stopped-flow methods: absorption at 422 nm, tryptophyl fluorescence at around 340 nm, circular dichroism (CD) at 222 nm, CD at 260 nm, and CD at 422 nm. In the refolding process, we detected three phases with rate constants of > 1 x 10(2) s-1, (4.5-9.3) s-1, and (2-5) x 10(-3) s-1. In the fastest phase, a substantial amount of secondary structure (approximately 40%) is formed within the dead time of the CD stopped-flow apparatus (10.7 ms). The kinetic intermediate populated in the fastest phase is shown to capture a hemindicyanide, suggesting that a "heme pocket precursor" recognized by hemindicyanide must be constructed within the dead time. In the middle phase, most of secondary and tertiary structures, especially around the captured hemindicyanide, have been constructed. In the slowest phase, we detected a minor structural rearrangement accompanying the ligand-exchange reaction in the fifth coordination of ferric iron. We present a possible model for the refolding process of myoglobin in the presence of the heme group.