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321.
Annette Eva Langkilde 《FEBS letters》2009,583(16):2600-13459
Protein fibrillation is first and foremost a structural phenomenon. Adequate structural investigation of the central conformational individuals of the fibrillation process is however exceedingly difficult. This is due to the nature of the process, which may be described as a dynamically evolving equilibrium between a large number of structural species. These are furthermore of highly diverging sizes and present in very uneven amounts and timeframes. Different structural methods have different strengths and limitations. These, and in particular recent advances within solution analysis of the undisturbed equilibrium using small angle X-ray scattering, are reviewed here. 相似文献
322.
Carolina Campos Francisco J. Fernández Edgar C. Sierra Francisco Fierro Adriana Garay Javier Barrios-González 《World journal of microbiology & biotechnology》2008,24(12):3017-3022
Penicillium chrysogenum low and high penicillin producing strains were transformed with a cosmid containing the whole penicillin biosynthetic gene
cluster. The cosmid library was constructed in a newly developed cosmid vector, IztapaCos, which allows cloning and direct
introduction of large DNA fragments in fungal recipients using phleomycin resistance as selection marker. The effect of increased
gene dosage on penicillin production was evaluated both in submerged (SmF) and solid-state fermentation (SSF). Transformants
from the low-producing strain Wis 54-1255, showed a 67.3 and 28.3% increased penicillin titer in SSF and SmF, respectively.
In transformants from the high-producing strain P2-32 the increase was 92.9 and 158.4% respectively. Strain P2-32 already
contains originally about 14 copies of the penicillin biosynthetic cluster, which shows that the strategy of increasing the
gene dosage is still valid for high copy-number strains. The different behavior of the two strains in each type of culture
is discussed, along with the practical implications for industrial penicillin production. 相似文献
323.
Key technologies for bioethanol production from lignocellulose 总被引:1,自引:0,他引:1
Controversies on bioethanol produced from straw mainly revolve around the unfitted economical feasibility and environmental concerns of the process, which attribute mainly to unilateral researches from own specialties of each scholar without regard to the characteristics of the straws themselves. To achieve an economical and environmentally-friendly system of bioethanol production from straw, a number of breakthroughs are needed, not only in individual process steps, but also in the balance and combination of these processes. This article gives an overview of the new technologies required and the advances achieved in recent years, especial progresses achieved in our group, based on the concept of fractional conversions. An eco-industrial multi-production pattern is established, by which the maximum efficacy and benefit of process can be achieved due to the production of many high-value co-products simultaneously with ethanol. We believed that, in the future, the bioethanol production from straw will be competitive economically and environmentally. 相似文献
324.
Zuming Li Zhihui Bai Baoguo Zhang Huijun Xie Qing Hu Chunbo Hao Wentong Xue Hongxun Zhang 《World journal of microbiology & biotechnology》2005,21(8-9):1483-1486
Summary A Bacillus strain capable of growing under highly alkaline conditions was isolated from a sample of alkaline soil. The isolate was a
Gram-positive, spore-forming, aerobic, alkaliphilic bacterium and was designated as strain S-2. Growth of the strain was observed
in the pH range of 7–12 and temperature range of 4–40 °C. Sequence analysis of the 16S rDNA of the strain revealed more than
99% homology with the strains of Bacillus gibsonii. The S-2 strain was confirmed as B. gibsonii by comparing its physiological and biochemical characteristics with the B. gibsonii DSM 8722 strain. The S-2 strain could use sugar beet pulp as the carbon source as well as the pectinase inducer to produce
extracellular alkaline pectinase by solid-state fermentation. The maximum polygalacturonase yield of 3600 U/g dry sugar beet
pulp was obtained at 35 °C after 48 h of incubation. 相似文献
325.
《Structure (London, England : 1993)》2023,31(3):230-243
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326.
We study the uniformly 13C,15N isotopically enriched Escherichia coli multidrug resistance transporter EmrE using MAS solid-state NMR. Solid-state NMR can provide complementary structural information as the method allows studying membrane proteins in their native environment as no detergent is required for reconstitution. We compare the spectra obtained from wildtype EmrE to those obtained from the mutant EmrE-E14C. To resolve the critical amino acid E14, glutamic/aspartic acid selective experiments are carried out. These experiments allow to assign the chemical shift of the carboxylic carbon of E14. In addition, spectra are analyzed which are obtained in the presence and absence of the ligand TPP+. 相似文献
327.
Mass transfer limitations in solid-state digestion 总被引:1,自引:0,他引:1
D.J. Martin 《Biotechnology letters》1999,21(9):809-814
The biodegradation of waste placed in layers was studied in 500-ml lysimeters, without leachate recycle. All four became methanogenic within 100 days but the steady-state biogas output only reached 0.09 l kg–1 d–1, whereas an earlier study on a mixed feedstock had yielded 1.8 l kg–1 d–1. A novel physical model of solid-state digestion is deduced, implying a crucial role for mass transfer processes, with successful operation only within a limited range of diffusion rates. 相似文献
328.
Xinxin Shu Qianwu Chen Maomao Yang Miaomiao Liu Jizhen Ma Jintao Zhang 《Liver Transplantation》2023,13(1):2202871
The strategy of heteroatom doping and metal active sites can synergistically promote oxygen electrocatalysis. Especially, the combination of theoretical simulations with experimental results provides new opportunities to understand the electrocatalytic mechanism. Herein, the 3D carbon nanosheets aggregate with highly branched carbon nanotubes and cobalt active sites (CoCNTs/PNAs) is prepared via the facile self-assembly-pyrolysis strategy. The CoCNTs/PNAs electrocatalysts exhibit superior bifunctional activities to oxygen reduction (E1/2 = 0.925 V) and evolution (Ej = 10 = 1.54 V) reactions, surpassing those of Pt/C-RuO2 catalysts. The theoretical calculations reveal that the electronic interaction of cobalt sites and nitrogen-doped carbon matrix plays a critical role in boosting the bifunctional electrocatalytic performance. Additionally, the rechargeable Zn-Air battery (ZAB) assembled with aqueous electrolyte exhibits the largest power density of 371.6 mW cm−2 and outstanding cycling durability (over 2000 h). Furthermore, all-solid-state cable-type ZAB delivers high flexibility with good cycling stability and high energy efficiency (76.5%). This work will open a new avenue to adjust the metal-carbon support interaction for functional electrocatalysis via hierarchical porous structure design. 相似文献
329.
Jianneng Liang Dachang Chen Keegan Adair Qian Sun Nathaniel Graham Holmes Yang Zhao Yipeng Sun Jing Luo Ruying Li Li Zhang Shangqian Zhao Shigang Lu Huan Huang Xiaoxing Zhang Chandra Veer Singh Xueliang Sun 《Liver Transplantation》2021,11(1):2002455
Polyethylene oxide (PEO) based solid polymer electrolytes (SPEs) are incompatible with the 4 V class cathodes such as LiCoO2 due to the limited electrochemical oxidation window of PEO. Herein, a number of binders including commonly used binders PEO, polyvinylidene fluoride (PVDF), and carboxyl-rich polymer (CRP) binders such as sodium alginate (Na-alginate) and sodium carboxymethyl cellulose, are studied for application in the 4 V class all-solid-state polymer batteries (ASSPBs). The results show ASSPBs with CRP binders exhibit superior cycling performance up to 1000 cycles (60% capacity retention, almost 10 times higher than those with PEO and PVDF binders). Synchrotron-based X-ray absorption spectroscopy (XAS), morphology studies and density functional theory studies indicate that, with their carboxyl groups, CRPs can strongly bind the electrode materials together, and work as coating materials to protect the cathode/SPE interface. Cyclic voltammetry studies indicate that CRP binders are more stable at high voltage compared to PEO and PVDF. The stability under high voltage and the coating property of CRP binders contribute to stable cathode/SPE interfaces as disclosed by the X-ray photoelectron spectroscopy and Co L-edge XAS results, enabling long cycling life, high performance 4 V class ASSPBs. 相似文献
330.
Aachal A. Sharma M. Rakshita Payal P. Pradhan K. A. K. Durga Prasad Siju Mishra K. Jayanthi D. Haranath 《Luminescence》2023,38(9):1668-1677
Psoriasis is a noncontagious, long-lasting skin infection that affects many people around the world. Numerous therapeutic artificial treatments are available for the treatment of psoriasis, such as photodynamic therapy using broadband ultraviolet (UV) lamps, which have harmful effects on human skin. Similarly, the natural healing systems such as sunlight have a higher risk of sunburn and can cause dangerous forms of skin cancer. Significant light emission of a specific wavelength (in the UV range), and phosphor-based devices demonstrate the effectiveness of treating psoriasis without damaging the skin. Gd3+-doped calcium magnesium silicate [Ca2MgSi2O7:Gd3+,(CMS:Gd3+)] phosphor is one of the ideal phosphors that emit specific narrow UV wavelengths for curing psoriasis and is in great demand in the field of dermatology. Photoluminescence analysis at room temperature (~25°C) shows that the synthesized CMS:Gd3+ phosphor emits narrowband UV-B light with a peak intensity at 314 nm. Comparative studies of the standard action spectrum of psoriasis with the emission spectrum of the CMS:Gd3+ phosphor show that the synthesized phosphor was the most suitable material for treating a variety of diseases, including psoriasis, vitiligo, type-1 diabetes, dental disease, sleep and mood disorders, and other skin diseases. 相似文献