Glycosylation variants of a β-glucosidase secreted by a Taiwanese fungus, Chaetomella raphigera, exhibit variant-specific catalytic and biochemical properties

Cellulosic biomass is an abundant and promising energy source. To make cellulosic biofuels competitive against conventional fuels, conversion of rigid plant materials into sugars must become efficient and cost-effective. During cellulose degradation, cellulolytic enzymes generate cellobiose (β-(1→4)-glucose dimer) molecules, which in turn inhibit such enzymes by negative feedback. β-Glucosidases (BGLs) cleave cellobiose into glucose monomers, assisting overall cellulolytic activities. Therefore, BGLs are essential for efficient conversion of cellulosic biomass into biofuels, and it is important to characterize newly isolated BGLs for useful traits. Here, we report our discovery that the indigenous Taiwanese fungus Chaetomella raphigera strain D2 produces two molecular weight variants of a single BGL, D2-BGL (shortened to "D2"), which differ in O-glycosylation. The more extensively O-glycosylated form of native D2 (nD2L) has increased activity toward the natural substrate, cellobiose, compared to the less O-glycosylated form (nD2S). nD2L is more stable at 60°C, in acidic pH, and in the presence of the ionic detergent sodium dodecyl sulfate than nD2S. Furthermore, unlike nD2S, nD2L does not display substrate inhibition by an artificial substrate p-nitrophenyl glucopyranoside (pNPG), and the glucose feedback inhibition kinetics of nD2L is competitive (while it is non-competitive for nD2S), suggesting that these two glycovariants of D2 bind substrates differently. Interestingly, D2 produced in a heterologous system, Pichia pastoris, closely mimics properties of nD2S. Our studies suggest that O-glycosylation of D2 is important in determining its catalytic and biochemical properties

Glycogen Phosphomonoester Distribution in Mouse Models of the Progressive Myoclonic Epilepsy, Lafora Disease

Glycogen is a branched polymer of glucose that acts as an energy reserve in many cell types. Glycogen contains trace amounts of covalent phosphate, in the range of 1 phosphate per 500–2000 glucose residues depending on the source. The function, if any, is unknown, but in at least one genetic disease, the progressive myoclonic epilepsy Lafora disease, excessive phosphorylation of glycogen has been implicated in the pathology by disturbing glycogen structure. Some 90% of Lafora cases are attributed to mutations of the EPM2A or EPM2B genes, and mice with either gene disrupted accumulate hyperphosphorylated glycogen. It is, therefore, of importance to understand the chemistry of glycogen phosphorylation. Rabbit skeletal muscle glycogen contained covalent phosphate as monoesters of C2, C3, and C6 carbons of glucose residues based on analyses of phospho-oligosaccharides by NMR. Furthermore, using a sensitive assay for glucose 6-P in hydrolysates of glycogen coupled with measurement of total phosphate, we determined the proportion of C6 phosphorylation in rabbit muscle glycogen to be ∼20%. C6 phosphorylation also accounted for ∼20% of the covalent phosphate in wild type mouse muscle glycogen. Glycogen phosphorylation in Epm2a−/− and Epm2b−/− mice was increased 8- and 4-fold compared with wild type mice, but the proportion of C6 phosphorylation remained unchanged at ∼20%. Therefore, our results suggest that C2, C3, and/or C6 phosphate could all contribute to abnormal glycogen structure or to Lafora disease

Callus Formation and Plant Regeneration of Herbs in Perilla Family

Effective methods of callus culture of herbs were studied to establish basic techniques for cell fusion and gene engineering. Eight basil cultivars, five species of Perilla family and a sweet basil were used, and following results were obtained. 1: Effects of phytohormones on callus formation. Callus formed effectively from hypocotyls and cotyledons of sterile seedlings cultured on MS medium supplemented with 0.1mg/12,4-D and BA. Plantlets succeeded in regenerating from callus cultured on MS medium supplemented with 0.1mg/I NAA and BA, but callus formation on a similar medium was inferior to that on MS medium supplemented with 2,4-D and BA. Callus formed best on MS medium supplemented with 2ip, among other cytokinins, but only BA actually induced regeneration of plantlets from callus. 2: Effects of age and different organs of explants on callus formation. Callus with similar weight formed from hypocotyls of young seedlings about 1-3 weeks after germination. The heaviest callus formed from cotyledons, followed by hypocotyls and roots. 3: Callus formation and regeneration of adventitious buds in eight basil cultivars. Calli formed cotyledons of lettuce basil, Anise basil, lemon basil, bush basil, sweet basil, purple raffles basil, dasil opal basil and cinnamon basil, in descending orderof weight, on MS medium supplemented with 2,4-D and 2ip. Callus from lettuce basil was three times as heavy as that from cinnamon basil. Callus formed on MS medium supplemented NAA and BA from cotyledone of all cultivars, but adventitious buds regenerated only from sweet basil, dark opal basil and bush basil. 4: Callus formation from six Perilla herbs. Callus fromed from hypocotyls and cotyledons of sweet basil, red perilla, green perilla, lemon balm, peppermint and sweet majoram in descending order of weight.ハーブの新しい植物育成のための細胞融合や遺伝子導入の基礎技術として、カルス培養の方法を検討した。材料として、カルス培養の為に、8品種のバジルおよび6種類のシソ科ハーブを用いて実験した。得られた結果は次の様であった。1:植物ホルモンの効果　カルスは、無菌実生の胚軸および子葉をMS培地に0.1mg/ℓの2,4-DとBAを添加した培地で培養することにより効果的に形成され、また同じ組成の培地または3mg/ℓ 2,4-Dと0.1mg/ℓ BA添加培地継代することにより高い増殖率を示したが、植物体は再分化しなかった。植物体の再分化は上記の材料を0.1mg/ℓ　のNAAと0.1または1.0mg/ℓのBAを添加した培地で培養することにより、カルスおよび不定根または不定芽を再分化することができたが、カルス形成は2,4-D添加培地に及ばさなかった。培地添加サイトカイニンとしては、カルス形成のためには2ipが大きなカルスを形成したが、植物体の再分化のためにはBAしか効果がなかった。2:植え付け外植体の差　無菌培養した実生の発芽1から3週間後の胚軸を外植体とした時、カルス形成には大きな差は見られなかった。無菌実生の1週間後の胚軸、根、子葉を外植体とした時、子葉が最も重いカルス形成し、次いて胚軸であった。3:8品種のバジルのカルス形成と不定芽再生2,4-Dと2ip添加培地でカルスの形成が最もよかったのはレタスバジルで次いでアニスバジル、レモンバジル、プッシュバジル、スイートバジル、パープルラフレスバジル、ダークオパールバジル、シナモンバジルの順で、レタスバジルはシナモンバジルの3.3倍の重さがあった。NAAとBA添加培地では、カルスはいずれの品種でも形成されたが、不定芽が再生されたのはスイートバジル、ダークオパールバジル、ブッシュバジルであった。4:6種のシソ科ハーブのカルス形成いずれの種類もカルスは形成されたが、スイートバジルに比較して生体重は軽く、アカジソがかろうじて匹敵するくらいで、アオジソ、レモンバーム、ペパーミント、スイートマジョラムの順に軽くなり、特にスイートマジョラムは形成外植体率も低かった。

Neuroprotective activation of astrocytes by methylmercury exposure in the inferior colliculus

Methylmercury (MeHg) is well known to induce auditory disorders such as dysarthria. When we performed a global analysis on the brains of mice exposed to MeHg by magnetic resonance imaging, an increase in the T1 signal in the inferior colliculus (IC), which is localized in the auditory pathway, was observed. Therefore, the purpose of this study is to examine the pathophysiology and auditory dysfunction induced by MeHg, focusing on the IC. Measurement of the auditory brainstem response revealed increases in latency and decreases in threshold in the IC of mice exposed to MeHg for 4 weeks compared with vehicle mice. Incoordination in MeHg-exposed mice was noted after 6 weeks of exposure, indicating that IC dysfunction occurs earlier than incoordination. There was no change in the number of neurons or microglial activity, while the expression of glial fibrillary acidic protein, a marker for astrocytic activity, was elevated in the IC of MeHg-exposed mice after 4 weeks of exposure, indicating that astrogliosis occurs in the IC. Suppression of astrogliosis by treatment with fluorocitrate exacerbated the latency and threshold in the IC evaluated by the auditory brainstem response. Therefore, astrocytes in the IC are considered to play a protective role in the auditory pathway. Astrocytes exposed to MeHg increased the expression of brain-derived neurotrophic factor in the IC, suggesting that astrocytic brain-derived neurotrophic factor is a potent protectant in the IC. This study showed that astrogliosis in the IC could be an adaptive response to MeHg toxicity. The overall toxicity of MeHg might be determined on the basis of the balance between MeHg-mediated injury to neurons and protective responses from astrocytes.This work was partly supported by a KAKENHI grant from the Japan Society for the Promotion of Science, grant numbers 15KK0024 and 17H04714 to Y.I. and 17K00569 to T.Y. This work was also financially supported in part by Tokushima Bunri University. This manuscript has been reviewed by a professional language editing service (American Journal Experts)

Potentiation of 17 beta-estradiol synthesis in the brain and elongation of seizure latency through dietary supplementation with docosahexaenoic acid

Several studies have shown that docosahexaenoic acid (DHA) attenuates epileptic seizures; however, the molecular mechanism by which it achieves this effect is still largely unknown. DHA stimulates the retinoid X receptor, which reportedly regulates the expression of cytochrome P450 aromatase (P450arom). This study aimed to clarify how DHA suppresses seizures, focusing on the regulation of 17β-estradiol synthesis in the brain. Dietary supplementation with DHA increased not only the expression of P450arom, but also 17β-estradiol in the cerebral cortex. While DHA did not affect the duration or scores of the seizures induced by pentylenetetrazole, DHA significantly prolonged the seizure latency. A P450arom inhibitor, letrozole, reduced 17β-estradiol levels and completely suppressed the elongation of seizure latency elicited by DHA. These results suggest that DHA delays the onset of seizures by promoting the synthesis of 17β-estradiol in the brain. DHA upregulated the expression of anti-oxidative enzymes in the cerebral cortex. The oxidation in the cerebral cortex induced by pentylenetetrazole was significantly attenuated by DHA, and letrozole completely inhibited this suppressive action. Thus, the anti-oxidative effects of 17β-estradiol may be involved in the prevention of seizures mediated by DHA. This study revealed that 17β-estradiol in the brain mediated the physiological actions of DHA.This work was partially supported by grants from the Ministry of Education, Culture, Sports, Science and Technology, Japan, KAKENHI for Y.I., K.I. and T.Y. (Nos. 26740024, 26460139 and 25340047), a grant from the Mishima Kaiun Memorial Foundation for Y.I. and a grant from the SKYLARK Food Science Institute for Y.I. This work was also financially supported in part by Tokushima Bunri University. We thank Y. Kamihashi, Y. Utagawa, and K. Kojima for their technical assistance. We also acknowledge S. Smiley-Jewell and M. Paz Prada for editing the manuscript. This manuscript has been checked by a professional language editing service, American Journal Experts

Evaluation of chemical-specific IgG antibodies in male workers from a urethane foam factory

Background: Plastic resins are complex chemicals that contain toluene diisocyanate (TDI) and/or trimellitic anhydride (TMA), which cause occupational allergies (OA), including respiratory allergies. Serum IgGs against TDI and TMA have been suggested as potential markers of the exposure status and as exploring cause of OA. Although TDI-specific IgG has been examined for suspected OA, TMA-specific IgG is not commonly evaluated in a urethane foam factory. This study therefore investigated both TDI- and TMA-specific IgGs in suspected OA patients and to evaluate the usefulness of the measurement of multiple chemical-specific IgG measurement for practical monitoring. Methods: Blood samples were collected from two male workers who developed respiratory allergies supposedly caused by occupational exposure to TDI and/or TMA for the presence of TDI- and TMA-specific IgGs. In addition, blood samples from 75 male workers from a urethane foam factory, along with 87 male control subjects, were collected in 2014 and tested for the same IgGs in 2014. The presence and levels of TDI- and TMA-specific serum IgGs were measured using dot blot assays. Results: We found that controls had mean concentrations of TDI- and TMA-specific IgGs of 0.98 and 2.10 μg/mL, respectively. In the two workers with respiratory allergies, the TDI-specific IgG concentrations were 15.6 and 9.51 μg/ mL, and TMA-specific IgG concentrations were 4.56 and 14.4 μg/mL, which are clearly higher than those in controls. Mean concentrations of TDI- and TMA-specific IgGs in the factory workers were 1.89 and 2.41 μg/mL, respectively, and are significantly higher than those of the controls (P < 0.001 and P < 0.026 for TDI- and TMA-specific IgGs, respectively). Conclusion: The workers suspected of OA showed an evidently high level of TDI- and TMA-specific IgG, and these levels in workers at the urethane foam factory were also significantly higher than those in controls. In conclusion, the measurement of TDI- and TMA-specific IgG among workers using plastic resins is helpful to monitor their exposure status.This study was funded by an Industrial Disease Clinical Research Grant (grant number 14040101-02 to M.T.) and the JSPS KAKENHI (grant numbers 22790546 and 25860472 to M.T.)

Glycan profiles of gp120 protein vaccines from four major HIV-1 subtypes produced from different host cell lines under non-GMP or GMP conditions

Envelope glycoprotein (Env) of human immunodeficiency virus type 1 (HIV-1) is an important target for the development of an HIV vaccine. Extensive glycosylation of Env is an important feature that both protects the virus from antibody responses and serves as a target for some highly potent broadly neutralizing antibodies. Therefore, analysis of glycans on recombinant Env proteins is highly significant. Here we present glycosylation profiles of recombinant gp120 proteins from four major clades of HIV-1 (A, B, C, and AE) produced either as research-grade material in 293 and CHO cells or as two independent lots of clinical material under GMP conditions. Almost all potential N-linked glycosylation sites were at least partially occupied in all proteins. The occupancy rates were largely consistent among proteins produced under different conditions, although a few sites showed substantial variability even between two GMP lots. Our data confirmed previous studies in the field showing high abundance of oligomannose on Env protein, with 40-50% of glycans having Man5-Man9 on all four proteins under all production conditions. Overall the differences in occupancy and glycan forms among Env from different subtypes produced under different conditions were less dramatic than anticipated and antigenicity analysis with a panel of six monoclonal antibodies showed that all four gp120s maintained their antibody-binding profiles, including antibodies that recognize glycan forms. Such findings have major implications to the final production of a clinical HIV vaccine including Env glycoprotein components. IMPORTANCE HIV-1 Env protein is a major target for the development of an HIV-1 vaccine. Env is covered with a large number of sugar-based glycan forms - about 50% of the Env molecular weight is composed of glycans. Glycan analysis of recombinant Env proteins is important to understand its roles in vial pathogenesis and immune responses. The current report presents the first extensive comparison of glycosylation patterns of recombinant gp120 proteins from four major clades of HIV-1 produced in two different cell lines, grown at either laboratory condition or at 50L GMP scale across different lots. Information learned in this study is valuable for the further design and production of HIV-1 Env proteins as the critical components of HIV-1 vaccine formulations

Altered distribution of plasma PAF-AH between HDLs and other lipoproteins in hyperlipidemia and diabetes mellitus

Platelet-activating factor acetylhydrolase (PAF-AH) is a phospholipase A2 associated with lipoproteins that hydrolyzes platelet-activating factor (PAF) and oxidized phospholipids. We have developed an ELISA for PAF-AH that is more sensitive than previous methods, and have quantified HDL-associated and non-HDL-associated PAF-AH in healthy, hyperlipidemic, and diabetic subjects. In healthy subjects, plasma total PAF-AH concentration was positively correlated with PAF-AH activity and with plasma total cholesterol, triacylglycerol, LDL cholesterol and apolipoprotein B (apoB) concentrations (all P < 0.01). HDL-associated PAF-AH concentration was correlated positively with plasma apoA-I and HDL cholesterol. Subjects with hyperlipidemia (n = 73) and diabetes mellitus (n = 87) had higher HDL-associated PAF-AH concentrations than did controls (P < 0.01). Non-HDL-associated PAF-AH concentration was lower in diabetic subjects than in controls (P < 0.01). Both hyperlipidemic and diabetic subjects had lower ratios of PAF-AH to apoB (P < 0.01) and higher ratios of PAF-AH to apoA-I (P < 0.01) than did controls. Our results show that the distribution of PAF-AH mass between HDLs and LDLs is determined partly by the concentrations of the lipoproteins and partly by the mass of enzyme per lipoprotein particle, which is disturbed in hyperlipidemia and diabetes mellitus

Associations between metal concentrations in whole blood and placenta previa and placenta accreta: the Japan Environment and Children’s Study (JECS)

Background: Placenta previa and placenta accreta associate with high morbidity and mortality for both mothers and fetus. Metal exposure may have relationships with placenta previa and placenta accreta. This study analyzed the associations between maternal metal (cadmium [Cd], lead [Pb], mercury [Hg], selenium [Se], and manganese [Mn]) concentrations and placenta previa and placenta accreta. Methods: We recruited 17,414 women with singleton pregnancies. Data from a self-administered questionnaire regarding the first trimester and medical records after delivery were analyzed. Maternal blood samples were collected to measure metal concentrations. The subjects were classified into four quartiles (Q1, Q2, Q3, and Q4) according to metal concentrations. Results: The odds ratio for placenta previa was significantly higher among subjects with Q4 Cd than those with Q1 Cd. The odds ratio for placenta previa was significantly higher for subjects with Q2 Pb than those with Q1 Pb. Conclusion: Participants with placenta previa had higher Cd concentrations. However, this study was crosssectional and lacked important information related to Cd concentration, such as detailed smoking habits and sources of Cd intake. In addition, the subjects in this study comprised ordinary pregnant Japanese women, and it was impossible to observe the relationship between a wide range of Cd exposure and placenta previa. Therefore, epidemiological and experimental studies are warranted to verify the relationship between Cd exposure and pregnancy abnormalities.This study was funded and supported by the Ministry of the Environment of Japan. The findings and conclusions of this article are solely the responsibility of the authors and do not represent the official views of this government agency

Impact of frailty on long-term mortality in older patients receiving intensive care via the emergency department

The aim of this study was to evaluate whether frailty was associated with 6-month mortality in older adults who were admitted to the intensive care unit (ICU) with an illness requiring emergency care. The investigation was a prospective, multi-center, observational study conducted among the ICUs of 17 participating hospitals. Patients >= 65 years of age who were admitted to the ICU directly from an emergency department visit were assessed to determine their baseline Clinical Frailty Scale (CFS) scores before the illness and were surveyed 6 months after admission. Among 650 patients included in the study, the median age was 79 years old, and overall mortality at 6 months was as low as 21%, ranging from 6.2% in patients with CFS 1 to 42.9% in patients with CFS >= 7. When adjusted for potential confounders, CFS score was an independent prognostic factor for mortality (one-point increase in CFS, adjusted risk ratio with 95% confidence interval 1.19 [1.09-1.30]). Quality of life 6 months after admission worsened as baseline CFS score increased. However, there was no association between total hospitalization cost and baseline CFS. CFS is an important predictor of long-term outcomes among critically ill older patients requiring emergent admission