Crystal structures of TdsC, a dibenzothiophene monooxygenase from the thermophile Paenibacillus sp A11-2, reveal potential for expanding its substrate selectivity

Sulfur compounds in fossil fuels are a major source of environmental pollution, and microbial desulfurization has emerged as a promising technology for removing sulfur under mild conditions. The enzyme TdsC from the thermophile Paenibacillus sp. A11-2 is a two-component flavin-dependent monooxygenase that catalyzes the oxygenation of dibenzothiophene (DBT) to its sulfoxide (DBTO) and sulfone (DBTO2) during microbial desulfurization. The crystal structures of the apo and flavin mononucleotide (FMN)-bound forms of DszC, an ortholog of TdsC, were previously determined, although the structure of the ternary substrate–FMN–enzyme complex remains unknown. Herein, we report the crystal structures of the DBT–FMN–TdsC and DBTO–FMN–TdsC complexes. These ternary structures revealed many hydrophobic and hydrogen-bonding interactions with the substrate, and the position of the substrate could reasonably explain the two-step oxygenation of DBT by TdsC. We also determined the crystal structure of the indole-bound enzyme because TdsC, but not DszC, can also oxidize indole, and we observed that indole binding did not induce global conformational changes in TdsC with or without bound FMN. We also found that the two loop regions close to the FMN-binding site are disordered in apo-TdsC and become structured upon FMN binding. Alanine substitutions of Tyr-93 and His-388, which are located close to the substrate and FMN bound to TdsC, significantly decreased benzothiophene oxygenation activity, suggesting their involvement in supplying protons to the active site. Interestingly, these substitutions increased DBT oxygenation activity by TdsC, indicating that expanding the substrate-binding site can increase the oxygenation activity of TdsC on larger sulfur-containing substrates, a property that should prove useful for future microbial desulfurization applications

Gene Expression Profiles of the Small Intestinal Mucosa of Dogs Repeatedly Infected with the Cestode \u3ci\u3eEchinococcus multilocularis\u3c/i\u3e

The data set presented in this article is related to a previous research article entitled, The timing of worm exclusion in dogs repeatedly infected with the cestode Echinococcus multilocularis (Kouguchi et al., 2016). This article describes the genes \u3e2 fold up- or down-regulated in the first- and repeated-infection groups compared to the healthy controls group. The gene expression profiles were generated using the Agilent-021193 Canine (V2) Gene Expression Microarray (GPL15379). The raw and normalized microarray data have been deposited with the Gene Expression Omnibus (GEO) database under accession number GSE105098

Adult Worm Exclusion and Histological Data of Dogs Repeatedly Infected with the Cestode \u3ci\u3eEchinococcus multilocularis\u3c/i\u3e

The data presented in this article are related to a previously published research article titled The timing of worm exclusion in dogs repeatedly infected with the cestode Echinococcus multilocularis (Kouguchi et al. 2016). This data describe a comparison of worm exclusion in the early stage of infection (1 day and 6 days post-infection) between dogs infected for the first time (control group) and dogs repeatedly infected with the parasite 4 times (repeated infection groups). We observed that 6 days post reinfection, the number of adult worms in repeated-infection groups decreased by 88.7% compared with the control group. Histological analysis comparison of the small intestinal mucosa from healthy, first infected, and repeatedly infected dogs are also reported. We observed no clear pathological abnormality, except the shortening of microvillus in reinfected dogs. However, eosinophil accumulation and eosinophilic ulcers were observed in some reinfected dogs. This data could be useful as preliminary data to develop a final host vaccine for this parasite

Silkworm Pupae Function as Efficient Producers of Recombinant Glycoproteins with Stable-Isotope Labeling

Baculovirus-infected silkworms are promising bioreactors for producing recombinant glycoproteins, including antibodies. Previously, we developed a method for isotope labeling of glycoproteins for nuclear magnetic resonance (NMR) studies using silkworm larvae reared on an artificial diet containing 15N-labeled yeast crude protein extract. Here, we further develop this method by introducing a technique for the expression of isotope-labeled glycoproteins by silkworm pupae, which has several potential advantages relative to larvae-based techniques in terms of production yield, ease of handling, and storage. Here, we fed fifth instar larvae an artificial diet with an optimized composition containing [methyl-13C]methionine, leading to pupation. Nine-day-old pupae were then injected with recombinant Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid for expression of recombinant human immunoglobulin G (IgG). From the whole-body homogenates of pupae, 0.35 mg/pupa of IgG was harvested, which is a yield that is five times higher than can be obtained from larvae. Recombinant IgG, thus prepared, exhibited mainly three kinds of pauci-mannose-type oligosaccharides and had a 13C-enrichment ratio of approximately 80%. This enabled selective observation of NMR signals originating from the methionyl methyl group of IgG, confirming its conformational integrity. These data demonstrate the utility of silkworm pupae as factories for producing recombinant glycoproteins with amino-acid-selective isotope labeling

Structural basis for improved efficacy of therapeutic antibodies on defucosylation of their Fc glycans

Removal of the fucose residue from the N-glycans of the Fc portion of immunoglobulin G (IgG) results in a dramatic enhancement of antibody-dependent cellular cytotoxicity (ADCC) through improved affinity for Fcγ receptor IIIa (FcγRIIIa). Here, we present the 2.2-Å structure of the complex formed between nonfucosylated IgG1-Fc and a soluble form of FcγRIIIa (sFcγRIIIa) with two N-glycosylation sites. The crystal structure shows that one of the two N-glycans of sFcγRIIIa mediates the interaction with nonfucosylated Fc, thereby stabilizing the complex. However, fucosylation of the Fc N-glycans inhibits this interaction, because of steric hindrance, and furthermore, negatively affects the dynamics of the receptor binding site. Our results offer a structural basis for improvement in ADCC of therapeutic antibodies by defucosylation

ADAMTS13によるvon Willebrand因子の切断増加は、本態性血小板血症患者における後天性von Willebrand症候群の発症に強く寄与する。

Background: Patients with essential thrombocythemia (ET) often experience bleeding associated with acquired von Willebrand syndrome (AVWS) when the platelet count is markedly increased. Objective: We investigated whether von Willebrand factor (VWF) degradation is enhanced in patients with ET. Methods: Seventy patients with ET underwent VWF multimer (VWFM) analysis and measurement of VWF-related parameters. We calculated the VWFM index, defined as the ratio of intensities of a patient's molecular weight-categorized VWFMs, and those of a healthy subject's, using densitometric analysis. VWF degradation product (DP) was measured via ELISA using a monoclonal antibody that specifically recognizes Y1605 at the C-terminal boundary, which is exposed following ADAMTS13-mediated cleavage of the Y1605-M1606 bond of the VWF A2 domain. Results: Patients with higher platelet counts had a significantly reduced high molecular weight (HMW)-VWFM index and an increased VWF-DP: VWF antigen (Ag) ratio compared to those with lower platelet counts. On multivariate analysis, the VWF-DP/ VWF:Ag ratio was an independent predictor of the HMW-VWFM index. Patients who underwent cytoreductive therapy had a significantly higher HMW-VWFM index and lower VWF-DP/ VWF:Ag ratio than those who did not. Among individual patients, there was also a significant increase in the HMW-VWFM index and a decrease in the VWF-DP/ VWF:Ag ratio after cytoreductive therapy compared to pre-therapy values. Conclusion: In patients with ET, an increased platelet count is associated with enhanced cleavage of VWF at the Y1605-M1606 bond, primarily by ADAMTS13, leading to AVWS. Cytoreductive therapy reduces the platelet count, prevents excessive VWF cleavage, and improves VWFM distributions.博士（医学）・甲第881号・令和5年3月15

Polyclonal Immunoglobulin Recovery after Autologous Stem Cell Transplantation Is an Independent Prognostic Factor for Survival Outcome in Patients with Multiple Myeloma

We retrospectively analyzed multiple myeloma (MM) patients who underwent autologous stem cell transplantation (ASCT) without maintenance therapy to assess the impact of recovery of normal immunoglobulin (Ig) on clinical outcomes. The recovery of polyclonal Ig was defined as normalization of all values of serum IgG, IgA, and IgM 1 year after ASCT. Among 50 patients, 26 patients showed polyclonal Ig recovery; 14 patients were in ≥complete response (CR) and 12 remained in non-CR after ASCT. The patients with Ig recovery exhibited a significantly better progression-free survival (PFS, median, 46.8 vs. 26.7 months, p = 0.0071) and overall survival (OS, median, not reached vs. 65.3 months, p < 0.00001) compared with those without Ig recovery. The survival benefits of Ig recovery were similarly observed in ≥CR patients (median OS, not reached vs. 80.5 months, p = 0.061) and non-CR patients (median OS, not reached vs. 53.2 months, p = 0.00016). Multivariate analysis revealed that non-CR and not all Ig recovery were independent prognostic factors for PFS (HR, 4.284, 95%CI (1.868–9.826), p = 0.00059; and HR, 2.804, 95%CI (1.334–5.896), p = 0.0065, respectively) and also for OS (HR, 8.245, 95%CI (1.528–44.47), p = 0.014; and HR, 36.55, 95%CI (3.942–338.8), p = 0.0015, respectively). Therefore, in addition to the depth of response, the recovery of polyclonal Ig after ASCT is a useful indicator especially for long-term outcome and might be considered to prevent overtreatment with maintenance therapy in transplanted patients with MM

Effect of the anti-parasitic compounds pyrvinium pamoate and artemisinin in enzymatic and culture assays: Data on the search for new anti-echinococcal drugs

The dataset presented herein is related to a previous research article titled “Mitochondrial Complex III in Larval Stage of Echinococcus multilocularis as a Potential Chemotherapeutic Target and in vivo Efficacy of Atovaquone Against Primary Hydatid Cysts” [1]. In this report, data were collected by screening drugs for echinococcosis. We investigated the inhibitory activities of artemisinin and pyrvinium pamoate against the mitochondrial respiratory enzymes in E. multilocularis protoscoleces. Artemisinin did not inhibit mitochondrial complexes I, II, and III. However, pyrvinium pamoate inhibited complex I at 11 μM,although complexes II and III were not inhibited. In the culture assay, E. multilocularis protoscoleces were treated with atovaquone (ATV), rotenone, praziquantel, artemisinin, and pyrvinium pamoate at a final concentration of 50 µM in different culture media. The viability of protoscoleces was compared under aerobic and anaerobic conditions via culture experiments. The survival days of E. multilocularis protoscoleces were evaluated in the drug-treated group compared with those in the non-treated group. The results of these culture assays revealed that praziquantel and artemisinin did not eliminate the protoscoleces under both aerobic and anaerobic conditions. However, a stronger elimination ability was observed with the co-administration of praziquantel or artemisinin with ATV than with ATV alone under aerobic conditions. Pyrvinium pamoate completely killed protoscoleces at 5 and 7 days under aerobic and anaerobic conditions, respectively. Pyrvinium pamoate behaved identically to rotenone, the complex I inhibitor, in the culture treatment assay.The data serve as a reference for the development of novel anti-echinococcal drugs