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Higuchi S, Kabeya Y, Nishina Y, Miura Y, Yoshino H. Feasibility and safety of non-contrast percutaneous coronary intervention in patients with complicated acute coronary syndrome. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.1751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Contrast-induced acute kidney injury (CI-AKI) occurs in 10% to 20% of acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI), resulting in a poor short- and long-term prognosis. Reducing the amount of contrast medium can prevent CI-AKI.
Objectives
This study aimed to examine the feasibility and safety of non-contrast PCI in patients with ACS.
Methods
The study was a prospective and single-center registry. Successful non-contrast PCI was confirmed when contrast medium was not injected from the guiding catheter engagement to wire removal in ad-hoc PCI. Coronary angiography after the PCI procedure was permitted once. CI-AKI was defined as an increase in the serum creatinine of ≥0.5 mg/dL from or ≥1.25 times the baseline within 72 hours after PCI. Worsening renal function (WRF) was defined as an increase in the serum creatinine of ≥0.3 mg/dL from baseline after the PCI.
Results
The present study included 106 lesions from 81 patients. Forty-eight lesions were (45%) type C lesions. Successful non-contrast PCI was performed in 95 lesions (90%). CI-AKI was observed in 4 (5%); coronary perforation, 0; no/slow flow, 9 (11%); periprocedural death, 0. The follow-up period was 348 (190–492) days. Successful non-contrast PCI was not associated with the incidence of CI-AKI. However, WRF at 6-month was observed in 18 individuals (22%). Successful non-contrast PCI was inversely associated with WRF (hazard ratio, 0.28; 95% confidence interval, 0.09–0.90) after adjustment for renal function.
Conclusions
The present study suggests that non-contrast PCI is feasible and safe in ACS patients with complex lesions.
Funding Acknowledgement
Type of funding source: None
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Nizami M, Nishina Y, Yamamoto T, Shinoda-Ito Y, Takashiba S. Functionalized Graphene Oxide Shields Tooth Dentin from Decalcification. J Dent Res 2019; 99:182-188. [DOI: 10.1177/0022034519894583] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
This in vitro study assessed the efficacy of functionalized graphene oxide (f-GO) nanocomposites on the decalcification of dentin, because dental caries of the root surface is becoming one of the new problems in aged society. Hydroxyapatite plates (HAP) and dentin slices were coated with f-GO nanocomposites by comparing them to silver diamine fluoride as a positive control, then treated with decalcification solutions such as ethylenediaminetetraacetic acid and citrate at 37°C for 24 h. Scanning electron microscopy (SEM) revealed significant protection of the surface morphology of HAP and dentin. On the other hand, a cariogenic Streptococcus mutans growth was inhibited by f-GO nanocomposites. In addition, cytotoxicity of them to epithelial cells was much less than that of povidone-iodine, which is commonly used for oral disinfectant. We synthesized 5 different f-GO nanocomposites such as GO–silver (Ag), GO-Ag–calcium fluoride (CaF2), GO-CaF2, GO-zinc, and GO–tricalcium phosphate (Ca3(PO4)2). They were standardized by evaluating under SEM, transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetry analysis (TGA), and Raman spectra after being synthesized in an aseptic technique. The abilities of GO-Ag, GO-Ag-CaF2, and GO-CaF2 nanocomposites were most preventive for decalcification. In addition, GO-Ag and GO-Ag-CaF2 almost completely inhibited S. mutans growth. However, they did not exhibit cytotoxicity to epithelial cells except at the highest concentration (0.1 w/v%) of GO-Ag and GO-Ag-CaF2. Furthermore, these f-GO nanocomposites exhibited less or no discoloration of dentin, although commonly used silver diamine fluoride causes discoloration of dentin to black. Thus, these f-GO nanocomposites are useful to protect dental caries on the tooth root that becomes a social problem in aged society.
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Nishina Y, Niino M, Higashi T. Approach for Compensation System of Asbestos-Related Lung Cancer. Eur J Public Health 2019. [DOI: 10.1093/eurpub/ckz186.321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The health hazards of asbestos have been globally recognized, especially those among industrial workers with long-term exposure. Lung cancer is one such asbestos-related disease. It occurs not only among workers but also among residents with environmental exposure to asbestos. Patients with work-related exposure can receive occupational compensation, and patients with non-occupational exposure are supported by a separate compensation system in Japan. However, the latter is not well-known among clinicians, and a substantial number of patients may have been left out. We need an effective way to find patients eligible to receive benefits by better understanding the clinical conditions that characterize patients with asbestos-related lung cancer.
Methods
We conducted two types of research: 1. Comparison of clinical characteristics between compensation system recipients (N = 65) and general lung cancer patients diagnosed in 2015, using Japan’s National Database of Hospital-Based Cancer Registry.
2. Estimation of the frequency of pleural plaques among lung cancer patients by double-checking CT scan images of a random sample of lung cancer patients obtained from the HBCR national database (N = 3585).
Results
Patients with squamous cell carcinoma are twice as likely asbestos-induced as patients with other histology overall after adjusting for age, sex and cancer stages, but not smoking status and history. As many as 20% of the CT images were read inconsistently between two radiologists or respiratory disease doctors and we could not obtain the accurate rate of candidacy for the compensation system.
Conclusions
We require more accurate information about pathological characteristics by controlling for smoking status and history among compensation recipients. For radiologic interpretation, more effective education is needed for the radiologists and respiratory disease doctors who treat lung cancer patients.
Key messages
Specific information about asbestos-related lung cancer would lead clinicians to correctly identify asbestos-related lung cancer. Educational system for clinicians would help patients to receive the benefit of compensation.
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El-Hout SI, Suzuki H, El-Sheikh SM, Hassan HMA, Harraz FA, Ibrahim IA, El-Sharkawy EA, Tsujimura S, Holzinger M, Nishina Y. Tuning the redox potential of vitamin K 3 derivatives by oxidative functionalization using a Ag(i)/GO catalyst. Chem Commun (Camb) 2018; 53:8890-8893. [PMID: 28740985 DOI: 10.1039/c7cc03910g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We propose herein initial results to develop optimum redox mediators by the combination of computational simulation and catalytic functionalization of the core structure of vitamin K3. We aim to correlate the calculated energy value of the LUMO of different vitamin K3 derivatives with their actual redox potential. For this, we optimized the catalytic alkylation of 1,4-naphthoquinones with a designed Ag(i)/GO catalyst and synthesized a series of molecules.
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Nishina Y, Komiya T, Motoyama R, Yamazaki M, Hiroyoshi Y, Higashihara M, Shibukawa M, Sunagawa M, Kato T, Takanashi S, Kouda S, Sengoku R, Kanemaru K, Murayama S. Safety and efficacy of alteplase in the treatment of extremely old patients of acute ischemic stroke. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.1786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Shibukawa M, Shibukawa M, Sengoku R, Yamazaki M, Nishina Y, Kanemaru K, Murayama S. Evaluation of orthostatic hypotension in Parkinson disease by measuring the catecholamine level and using a Cardiac MIBG scintigraphy. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.2587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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7
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Morita S, Suzaki S, Ishizaki U, Endo K, Yamazaki H, Nishina Y, Sakai S. Radiation dose reduction in patients using dynamic trace digital angiography and spot fluoroscopy during adrenal venous sampling. J Vasc Interv Radiol 2017. [DOI: 10.1016/j.jvir.2016.12.1200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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8
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Okada R, Fujimagari M, Koya E, Hirose Y, Sato T, Nishina Y. Expression Profile of NOTCH3 in Mouse Spermatogonia. Cells Tissues Organs 2017; 204:283-292. [PMID: 29161703 DOI: 10.1159/000481772] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2017] [Indexed: 12/17/2022] Open
Abstract
Stable and sustainable spermatogenesis is supported by the strict regulation of self-renewal and differentiation of spermatogonial stem cells (SSC), which are a rare population of undifferentiated spermatogonia. It has been revealed that some signaling factors regulate the self-renewal of SSC; however, the molecular mechanism of SSC maintenance is still not completely understood. Notch signaling is an evolutionarily conserved juxtacrine signaling that plays important roles in the cell fate determination of various tissue stem cells. Recently, analyses of loss- and gain-of-function suggested that Notch signaling was necessary for normal spermatogenesis. However, the expression of Notch signal components in spermatogonia is still unclear. Here, we analyzed the distribution of NOTCH3-expressing spermatogonia and the target genes. Double immunostaining with differentiation markers revealed that NOTCH3 was expressed in some undifferentiated and differentiated spermatogonia in mouse testes. To define the target gene of Notch3 signaling in spermatogonia, we analyzed the mRNA expression pattern of Hes and Hey family genes during testis development. Hes1 abundance was decreased during testis development, suggesting that spermatogonia may express Hes1. Immunohistochemical analysis showed that HES1 was expressed in prepubertal spermatogonia, whereas it was expressed predominantly in adult Sertoli cells and weakly in adult spermatogonia. Furthermore, NOTCH3-HES1 double-positive spermatogonia were in pup and adult testes. These results suggest that Notch3 signaling in spermatogonia could promote Hes1 expression.
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Okada R, Hara T, Sato T, Kojima N, Nishina Y. The mechanism and control of Jagged1 expression in Sertoli cells. Regen Ther 2016; 3:75-81. [PMID: 31245476 PMCID: PMC6581826 DOI: 10.1016/j.reth.2016.02.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 02/08/2016] [Accepted: 02/15/2016] [Indexed: 01/25/2023] Open
Abstract
The regulation of Sertoli cells by some hormones and signaling factors is important for normal spermatogenesis. Notch signaling is considered to be necessary for normal spermatogenesis in mouse. In this study, we revealed two new facts about Sertoli cells by western blotting experiments on different types of primary cells and microdissected tubules. The first is that Sertoli cells express the Jagged1 ligand in mice testes. The second is that the expression level of Jagged1 oscillates in the seminiferous epithelial cycle. Therefore, we inferred that Jagged1 in Sertoli cells contributes to the Notch signaling involved in spermatogenesis. Furthermore, we examined the regulation of Jagged1 expression and found that Jagged1 expression was suppressed by cAMP signaling and was promoted by TNF-α signaling in Sertoli cells. When cAMP and TNF-α were simultaneously added to Sertoli cells, Jagged1 expression was suppressed. Therefore, cAMP signaling dominates Jagged1 expression over TNF-α signaling. These results suggest that cAMP signaling may cause the periodicity of Jagged1 expression in the seminiferous epithelial cycle, and controlling Jagged1 expression by adding TNF-α or cAMP may contribute to normal spermatogenesis in vitro. Jagged1 was expressed in Sertoli cells in mouse testes. The expression of Jagged1 oscillated in the seminiferous epithelial cycle. The expression of Jagged1 in Sertoli cells was upregulated by TNF-α and downregulated by cAMP.
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Morita S, Tajima T, Yamazaki H, Sonoyama Y, Nishina Y, Kenji O, Takagi T, Kondo T, Tanabe K, Sakai S. Screening of renal artery pseudoaneurysms by early postoperative contrast-enhanced computed tomography in patients without renal impairment after partial nephrectomy and prophylactic embolization. J Vasc Interv Radiol 2015. [DOI: 10.1016/j.jvir.2014.12.289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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11
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Zhou T, Koga H, Nogi M, Sugahara T, Nagao S, Nge TT, Suganuma K, Cui HW, Liu F, Nishina Y. Targeted kinetic strategy for improving the thermal conductivity of epoxy composite containing percolating multi-layer graphene oxide chains. EXPRESS POLYM LETT 2015. [DOI: 10.3144/expresspolymlett.2015.57] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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12
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Nishina Y. Die Polarisation der Comptonstreuung nach der Diracschen Theorie des Elektrons. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/bf01366454] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Fukunaga H, Yoshimura H, Nishina Y, Nagashima Y, Tachibana M. Label-free biomedical imaging of hydrodynamics in single human cells. ACTA ACUST UNITED AC 2010; 31:177-81. [PMID: 20622467 DOI: 10.2220/biomedres.31.177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Intracellular hydrodynamics is of considerable importance to regulate cellular functions. Using Raman microspectroscopy and imaging, we visualized the time-dependent changes of water concentration in single human acute promyelocytic leukemia HL-60 cells, and also showed the labelfree biomedical imaging of water molecules, lipids and proteins for analyzing molecular distribution. Taken together, our results demonstrated that we can distinguish between intracellular water and other major cell components, and that when the physiological status of cells changes with time, the Raman spectral intensities for intracellular water concentration also changes. Therefore, this biospectroscopic analysis of intracellular hydrodynamics can provide biomarkers to examine activities in dynamic living systems, and has significant potential in determining cell specificity for novel therapeutic approaches.
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Nishina Y. LVIII. On the L-absorption spectra of the elements from Sn (50) to W (74) and their relation to the atomic constitution. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/14786442508634634] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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15
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Nakaoka K, Goto T, Nishina Y. Emission mechanism in highly excited state of red HgI2. ACTA ACUST UNITED AC 2007. [DOI: 10.1007/bf02723535] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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16
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Miyahara I, Nakajima Y, Tokuoka K, Hirotsu K, Nishina Y, Shiga K, Setoyama C, Tamaoki H, Tojo H, Miura R. Three-dimensional structure of rat-liver acyl-CoA oxidase in complex with fatty acid. Acta Crystallogr A 2006. [DOI: 10.1107/s0108767306096942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Miyagawa S, Buchanan DL, Sato T, Ohta Y, Nishina Y, Iguchi T. Characterization of diethylstilbestrol-induced hypospadias in female mice. THE ANATOMICAL RECORD 2002; 266:43-50. [PMID: 11748570 DOI: 10.1002/ar.10033] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The urethral duct and vagina are formed from the urogenital sinus (UGS) during the early neonatal period in mice. Neonatal estrogen exposure results in hypospadias, or the malpositioning of vaginal and urethral openings, with wide cleft clitoris. We sought to characterize diethylstilbestrol (DES) influence on UGS morphogenesis and hypospadias formation. Newborn (day 0) and 1-4-day-old female mice (ICR/Jcl) were given (s.c.) oil or 3.0 microg DES. Animals were killed 24 hr later; then hypospadias formation and epithelial apoptosis and proliferation within the developing UGS were assessed. DES did not alter normal UGS morphogenesis by day 1, in comparison with controls. However, hypospadias formation was observed in DES-treated mice by day 3. In these mice, the distal dorsal urethral duct appeared to fuse with and open into the lower vaginal solid cord region. Further, DES treatment produced a gradual significant increase in dorsal urethral epithelial apoptosis (P < 0.05) just prior to and during fusion and hypospadias formation. DES-induced urethral epithelial and sinus cord proliferation appeared significantly increased (P < 0.05) and unchanged, respectively, just prior to fusion. By day 5, DES-treated mice exhibited wide cleft clitoris. In addition, if DES was given on day 3 or 5, a gradual, distinct caudal shift in the vaginal-urethral junction was observed compared to mice treated on days 0-2. Although hypospadias was not induced when neonates were given DES on day 7, these mice continued to display early vaginal opening. Dose-response analysis indicated that 0.03 microg DES for 5 days is the lowest known critical dose for hypospadias induction. We have shown for the first time that DES-induced hypospadias onset may primarily be the result of changes in developing dorsal urethral epithelial cell apoptotic and proliferative activity, and that the location of DES-induced hypospadias formation is dependent on age at time of exposure.
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Nakajima Y, Miyahara I, Hirotsu K, Nishina Y, Shiga K, Setoyama C, Tamaoki H, Miura R. Crystallization and preliminary X-ray characterization of rat liver acyl-CoA oxidase. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2001; 57:1680-1. [PMID: 11679743 DOI: 10.1107/s0907444901012732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2001] [Accepted: 07/27/2001] [Indexed: 11/10/2022]
Abstract
A recombinant form of the flavoenzyme acyl-CoA oxidase from rat liver has been crystallized by the hanging-drop vapour-diffusion technique using PEG 20 000 as a precipitating agent. The crystals grew as yellow prisms, with unit-cell parameters a = 71.05, b = 87.29, c = 213.05 A, alpha = beta = gamma = 90 degrees. The crystals exhibit the symmetry of space group P2(1)2(1)2(1) and are most likely to contain a dimer in the asymmetric unit, with a V(M) value of 2.21 A(3) Da(-1). The crystals diffract to a resolution of 2.5 A at beamline BL6A of the Photon Factory. Two heavy-atom derivatives have been identified.
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Nishina Y, Sato K, Shi R, Setoyama C, Miura R, Shiga K. On the ligands in charge-transfer complexes of porcine kidney flavoenzyme D-amino acid oxidase in three redox states: a resonance Raman study. J Biochem 2001; 130:637-47. [PMID: 11686926 DOI: 10.1093/oxfordjournals.jbchem.a003029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To investigate the structural modulation of ligands and their interaction in the active-site nanospace when they form charge-transfer (CT) complexes with D-amino acid oxidase (DAO) in three redox states, we compared Raman bands of the ligands in complex with DAO with those of ligands free in solution. Isotope-labeled ligands were synthesized for assignments of observed bands. The COO(-) stretching of ligands observed around, 1,370 cm(-1) downshifted by about 17 cm(-1) upon complexation with oxidized, semiquinoid and reduced DAO, except for the case of reduced DAO-N-methylisonicotinate complex (8 cm(-1) downward shift); the interaction mode of the carboxylate group with the guanidino group of Arg283 and the hydroxy moiety of Tyr228 of DAO is similar in the three redox states. The C=N stretching mode (1,704 cm(-1)) of Delta(1)-piperideine-2-carboxylate (D1PC) downshifted to 1,675 and 1,681 cm(-1) upon complexation with reduced and semiquinoid DAO, respectively. The downward shifts indicate that the C=N bond is weakened upon the complexation. This is probably due mainly to charge-transfer (CT) interaction between D1PC and semiquinoid or reduced flavin, i.e., the partial electron donation from the highest occupied molecular orbital (HOMO) of reduced flavin or a singly occupied molecular orbital (SOMO) of semiquinoid flavin to the lowest unoccupied molecular orbital (LUMO), an antibonding orbital, of D1PC. This speculation was supported by the finding that the magnitude of the shift is smaller by 5 cm(-1) (observed at 1,680 cm(-1)) in the case of reduced DAO reconstituted with 7,8-Cl(2)-FAD, whose reduced form has lower electron-donating ability than natural reduced FAD. The amount of electron flow was estimated by applying the theory of Friedrich and Person [(1966) J. Chem. Phys. 44, 2166-2170] to these complexes; the amounts of charge transfer from reduced FAD and reduced 7,8-Cl(2)-FAD to D1PC were estimated to be about 10 and 8% of one electron, respectively, in the CT complexes of reduced DAO with D1PC.
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Abstract
To investigate the precise localization of cytoplasmic gamma actin in skeletal muscle and the relationship to dystrophin molecules, we designed an antibody against the N-terminal peptide of cytoplasmic gamma actin. Western blot analysis using SDS-PAGE and isoelectric focusing (IEF) gel revealed that the antibody reacted only with the actin isoforms having gamma motility, confirming that the antibody is specific to the cytoplasmic (nonmuscle) gamma actin. Immunohistochemical analysis of the skeletal muscle of the adult mouse revealed a dot-like staining pattern of the antibody in transverse sections and a striated staining pattern in longitudinal sections. The double immunostaining technique revealed the colocalization of cytoplasmic gamma actin with alpha-actinin, implying the localization of the actin on the Z-disc. Contrary to previous findings (1), we did not detect the colocalization of cytochrome oxidase, a mitochondria marker, with this actin.
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Sato Y, Ogawa T, Motomiya K, Shinoda K, Jeyadevan B, Tohji K, Kasuya A, Nishina Y. Purification of MWNTs Combining Wet Grinding, Hydrothermal Treatment, and Oxidation. J Phys Chem B 2001. [DOI: 10.1021/jp002817k] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Matsubara T, Ohshiro T, Nishina Y, Izumi Y. Purification, characterization, and overexpression of flavin reductase involved in dibenzothiophene desulfurization by Rhodococcus erythropolis D-1. Appl Environ Microbiol 2001; 67:1179-84. [PMID: 11229908 PMCID: PMC92711 DOI: 10.1128/aem.67.3.1179-1184] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The dibenzothiophene (DBT)-desulfurizing bacterium, Rhodococcus erythropolis D-1, removes sulfur from DBT to form 2-hydroxybiphenyl using four enzymes, DszC, DszA, DszB, and flavin reductase. In this study, we purified and characterized the flavin reductase from R. erythropolis D-1 grown in a medium containing DBT as the sole source of sulfur. It is conceivable that the enzyme is essential for two monooxygenase (DszC and DszA) reactions in vivo. The purified flavin reductase contains no chromogenic cofactors and was found to have a molecular mass of 86 kDa and four identical 22-kDa subunits. The enzyme catalyzed NADH-dependent reduction of flavin mononucleotide (FMN), and the K(m) values for NADH and FMN were 208 and 10.8 microM, respectively. Flavin adenine dinucleotide was a poor substrate, and NADPH was inert. The enzyme did not catalyze reduction of any nitroaromatic compound. The optimal temperature and optimal pH for enzyme activity were 35 degrees C and 6.0, respectively, and the enzyme retained 30% of its activity after heat treatment at 80 degrees C for 30 min. The N-terminal amino acid sequence of the purified flavin reductase was identical to that of DszD of R. erythropolis IGTS8 (K. A. Gray, O. S. Pogrebinsky, G. T. Mrachko, L. Xi, D. J. Monticello, and C. H. Squires, Nat. Biotechnol. 14:1705-1709, 1996). The flavin reductase gene was amplified with primers designed by using dszD of R. erythropolis IGTS8, and the enzyme was overexpressed in Escherichia coli. The specific activity in crude extracts of the overexpressed strain was about 275-fold that of the wild-type strain.
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Uchida K, Tsuchida J, Tanaka H, Koga M, Nishina Y, Nozaki M, Yoshinaga K, Toshimori K, Matsumiya K, Okuyama A, Nishimune Y. Cloning and characterization of a complementary deoxyribonucleic acid encoding haploid-specific alanine-rich acidic protein located on chromosome-X. Biol Reprod 2000; 63:993-9. [PMID: 10993819 DOI: 10.1095/biolreprod63.4.993] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
We have isolated a cDNA clone encoding a germ cell-specific protein from an expression cDNA library prepared from the mouse testis using testis-specific polyclonal antibodies. Northern blot analysis showed a transcript of 1.1 kilobases exclusively expressed in haploid germ cells of the testis. Sequence analysis of the cDNA revealed one long open reading frame consisting of 238 deduced amino acids, rich in basic amino acids in the N-terminal one-third that also contained the nuclear localization signal, and rich in acidic amino acids, including two type of acidic alanine-rich repeats, in the rest of the deduced protein. The protein having a molecular weight of approximately 55 kDa and an isoelectric point of pH 4.3-4.7 was also exclusively detected in the testis by Western blot analysis. As the cDNA was located on chromosome-X, Halap-X (haploid-specific alanine-rich acidic protein located on chromosome-X) was proposed for the name of the protein encoded by the cDNA. Immunohistochemical observation revealed that the Halap-X protein was predominantly present in the nucleoplasm of round spermatids but gradually decreased as spermatids matured, followed by the subsequent appearance in the cytoplasm of elongating spermatids. Thus, the Halap-X protein was transferred from the nuclei to the cytoplasm during the spermatid maturation when the chromatin condensation and transformation of the nuclei occurred. The Halap-X may facilitate specific association of nuclear DNA with some basic chromosomal proteins and play important roles in the process of chromatin condensation.
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Nishina Y, Sato K, Miura R, Shiga K. Substrate recognition and activation mechanism of D-amino acid oxidase: a study using substrate analogs. J Biochem 2000; 128:213-23. [PMID: 10920257 DOI: 10.1093/oxfordjournals.jbchem.a022744] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We investigated the mechanism of recognition and activation of substrate by D-amino acid oxidase (DAO) by thermodynamical and spectrophotometric methods using zwitterionic ligands [N-methylisonicotinate (NMIN), trigonelline, and homarine] and monoanionic ligands as model compounds of the substrate and the product. In terms of the charge within the substrate D-amino acid, monoanionic (e.g., benzoate), zwitterionic (e.g., NMIN), and dianionic (e.g., terephthalate) ligands are thought to be good models for neutral, basic, and acidic amino acids, respectively, because when a substrate binds to DAO, as previously reported, the a-ammonium group (-NH(3)(+)) probably loses a proton to become neutral (-NH(2)) before the oxidation. Zwitterionic ligands can also be good model compounds of product in the purple complex (the complex of reduced DAO with the product imino acid), because the imino nitrogen of the imino acid is in a protonated cationic form. We also discuss electrostatic interaction, steric effect, and charge-transfer interaction as factors which affect the affinity of substrate/ligand for DAO. Monoanionic ligands have high affinity for neutral forms of oxidized and semiquinoid DAO, while zwitterionic ligands have high affinity for anionic forms of oxidized, semiquinoid, and reduced DAO; this difference was explained by the electrostatic interaction in the active site. The low affinity of homarine (N-methylpicolinate) for oxidized DAO, as in the case of o-methylbenzoate, is due to steric hindrance: one of the ortho carbons of benzoate is near the phenol carbons of Tyr228 and the other ortho carbon is near the carbonyl oxygen of Gly313. The correlation of the affinity of meta- and para-substituted benzoates for oxidized DAO with their Hammet's s values are explained by the HOMO-LUMO interaction between the phenol group of Tyr224 and the benzene ring of benzoate derivative. The pK(a) of neutral flavin [N(3)-H of oxidized flavin, N(5)-H of semiquinoid flavin, and N(1)-H of reduced flavin] decreases by its binding to the apoenzyme. The magnitude of the decrement is oxidized flavin < semiquinoid flavin < reduced flavin. The largest factor in the substantially low pK(a) of reduced flavin in DAO is probably the steric hindrance between the hydrogen atom of H-N(1)(flavin) and the hydrogen atom of H-N of Gly315, which becomes significant when a hydrogen is bound to N(1) of flavin.
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Mizutani H, Miyahara I, Hirotsu K, Nishina Y, Shiga K, Setoyama C, Miura R. Three-dimensional structure of the purple intermediate of porcine kidney D-amino acid oxidase. Optimization of the oxidative half-reaction through alignment of the product with reduced flavin. J Biochem 2000; 128:73-81. [PMID: 10876160 DOI: 10.1093/oxfordjournals.jbchem.a022732] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The three-dimensional structure of the purple intermediate of porcine kidney D-amino acid oxidase (DAO) was solved by cryo-X-ray crystallography; the purple intermediate is known to comprise a complex between the dehydrogenated product, an imino acid, and the reduced form of DAO. The crystalline purple intermediate was obtained by anaerobically soaking crystals of oxidized DAO in a buffer containing excess D-proline as the substrate. The dehydrogenated product, delta(1)-pyrrolidine-2-carboxylate (DPC), is found sandwiched between the phenol ring of Tyr 224 and the planar reduced flavin ring. The cationic protonated imino nitrogen is within hydrogen-bonding distance of the backbone carbonyl oxygen of Gly 313. The carboxyl group of DPC is recognized by the Arg 283 guanidino and Tyr 228 hydroxyl groups through ion-pairing and hydrogen-bonding, respectively. The (+)HN=C double bond of DPC overlaps the N(5)-C(4a) bond of reduced flavin. The electrostatic effect of the cationic nitrogen of DPC is suggested to shift the resonance hybridization of anionic reduced flavin toward a canonical form with a negative charge at C(4a), thereby augmenting the electron density at C(4a), from which electrons are transferred to molecular oxygen during reoxidation of reduced flavin. The reactivity of reduced flavin in the purple intermediate, therefore, is enhanced through the alignment of DPC with respect to reduced flavin.
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