MRS Communications
·
2022
·Vol. 12
·期 5
·937-943
·
IF 2.935
Shan Xinyuan,Li Xiaohua,Feng Hao,Ma Mengxiang,Cao Peng-Fei,Yang Dandan,Yang Huabin
With high capacity and low redox potential, Sn-based materials represent promising anodes for sodium-ion batteries (SIBs). However, the large volume expansion during the cycling process limits their application. Herein, we report a cost-effective, simple, and non-toxic SbSn/SP@C electrode for SIBs via ball milling process and sucrose reduction method. The SbSn/SP@C electrode exhibits high cycle stability and good reversible capacity for SIBs (400.3 mAh g −1 after 100 cycles). Consequently, SbSn/SP@C electrode can afford an effectively carbon-based conductive system, which buffers large volume change of SnSb alloy during the cycling process and provides promising electrochemical performance in Na storage. Graphical abstract
✓ 已验证
DOI
高影响因子
Nanoscale
·
2021
·Vol. 13
·期 6
·3817-3826
·
IF 7.79
Suzhen Kong,Dong Cai,Guifa Li,Xiangju Xu,Suya Zhou,Xinwei Ding,Yongqin Zhang,Shuo Yang,Xuemei Zhou,Huagui Nie,Shaoming Huang,Ping Peng,Zhi Yang
To overcome the shuttle effect in lithium–sulfur (Li–S) batteries, an sp/sp2 hybridized all-carbon interlayer by coating graphene (Gra) and hydrogen-substituted graphdiyne (HsGDY) with a specific surface area as high as 2184 m2 g−1 on a cathode is designed and prepared. The two-dimensional network and rich pore structure of HsGDY can enable the fast physical adsorption of lithium polysulfides (LiPSs). In situ Raman spectroscopy and ex situ X-ray photoelectron spectroscopy (XPS) combined with density functional theory (DFT) computations confirm that the acetylenic bonds in HsGDY can trap the Li+ of LiPSs owing to the strong adsorption of Li+ by acetylenic active sites. The strong physical adsorption and chemical anchoring of LiPSs by the HsGDY materials promote the conversion reaction of LiPSs to further mitigate the shuttling problem. As a result, Li–S batteries integrated with the all-carbon interlayers exhibit excellent cycling stability during long-term cycling with an attenuation rate of 0.089% per cycle at 1 C over 500 cycles.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2021
·
IF 3.493
Rong Wang,Xinqi Xu,Xuemei Yao,Hengtao Tang,Xin Ju,Liangzhi Li
Ribose-5-phosphate isomerase A (RpiA) is of great importance in biochemistry research, however its application in biotechnology has not been fully explored. In this study the activity of RpiA from Ochrobactrum sp. CSL1 (OsRpiA) towards D-allose was engineered based on sequential and structural analyses. Strategies of alanine scanning, rational design and saturated mutagenesis were employed to create three mutant libraries. A single mutant of K124A showed a 45 % activity improvement towards D-allose. The reaction properties of the mutant were analyzed, and a shift of optimal pH and higher thermal stability at low reaction temperatures were identified. The conversion of D-allose was also improved by 40 % using K124A, and higher activities on major substrates were found in the mutant’s substrate scope, implying its application potential in rare sugar preparation. Kinetics analysis revealed that K m of K124A mutant decreased by 12 % and the catalytic efficiency increased by 65 % towards D-allose. Moreover, molecular dynamics simulation illustrated the binding of substrate and K124A was more stable than that of the wild-type. The shorter distance and more relax bond angle between the catalytic residue of K124A and D-allose explained the activity improvement in detail. This study highlights the potential of OsRpiA as a biocatalyst for rare sugar preparation, and provides distinct evidences for its catalytic mechanism.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL MICROBIOLOGY
·
2021
·Vol. 23
·期 5
·2550-2563
·
IF 5.491
Shunyao Li,Kai Sun,Xin Yan,Chao Lu,Michael Gatheru Waigi,Juan Liu,Wanting Ling
Summary Novosphingobium sp. ES2-1 is an efficient 17 β -estradiol (E2)-degrading bacterium, which can convert E2 to estrone (E1), then to 4-hydroxyestrone (4-OH-E1) for subsequent oxidative cracking. In this study, the molecular bases for this process were elucidated. Two novel monooxygenase systems EstP and EstO were shown to catalyse the oxygenation of E1 and 4-OH-E1, respectively. EstP was a three-component cytochrome P450 monooxygenase system consisting of EstP1 (P450 monooxygenase), EstP2 (ferredoxin) and EstP3 (ferredoxin reductase). Ultraperformance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) analysis revealed that EstP catalysed the 4-hydroxylation of E1 to produce 4-OH-E1. The resultant 4-OH-E1 was further oxidized by a two-component monooxygenase system EstO consisting of EstO1 (flavin-dependent monooxygenases) and EstO2 (flavin reductase). UPLC-HRMS combined with 1 H-nuclear magnetic resonance analysis demonstrated that EstO catalysed the breakage of C9-C10 to yield a ring B-cleavage product. In addition, the oxygenase component genes estP1 and estO1 exhibited contrary inductive behaviours when exposed to different steroids, suggesting that EstP1-mediated 4-hydroxylation was E2-specific, whereas EstO1-mediated monooxygenation might be involved in the degradation of testosterone, androstenedione, progesterone and pregnenolone. This also implied that the mechanisms of the catabolism of different steroids by the same microorganism might be partially interlinked.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2021
·
IF 5.565
Li Xiang,Chaoyang Liu,Deng Liu,Liyuan Ma,Xuan Qiu,Hongmei Wang,Xiaolu Lu
Soils and waters are heavily contaminated by antimony in Xikuangshan (XKS) mine area. It is widely accepted that oxidative dissolution of sulfide minerals and aqueous dissolution are the most prevalent geochemical mechanisms for the release of Sb to the environment. Bosea sp. AS-1 is an antimonite-oxidizer isolated from the mine slag in Xikuangshan Sb mine. Whole genome sequencing revealed the presence of multiple sulfur-oxidizing genes, antimony (Sb) metabolism genes and carbon fixation genes in AS-1′s genome. We therefore hypothesized that under oxic conditions, AS-1 could mediate the oxidation of sulfide and Sb(III) in stibnite (Sb 2 S 3 ) and lead to the release of Sb. Indeed, strain AS-1 was discovered as an autotrophic Sb(III)-oxidizer. Antimony mobilization studies conducted with strain AS-1 showed significantly enhanced mobilization of Sb, and complete oxidation of released Sb and sulfur to Sb(V) and sulfate. In addition, AS-1 induced a faster release of Sb under heterotrophic condition, and new acicular minerals might form. These findings support the hypothesis that microorganisms play an important role in the mobilization and transformation of Sb in XKS mine area and may contribute to our further understanding of the Sb biogeochemical redox cycle in natural environment.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Microbiology
·
2021
·
IF 5.64
Zheng Qiuling,Meng Xiangjun,Cheng Mingyang,Li Yanfeng,Liu Yuanpeng,Chen Xuehong
Chitosanase is a significant chitosan-degrading enzyme involved in industrial applications, which forms chitooligosaccharides (COS) as reaction products that are known to have various biological activities. In this study, the gene csnS was cloned from a deep-sea bacterium Serratia sp. QD07, as well as over-expressed in Escherichia coli, which is a new chitosanase encoding gene. The recombinant strain was cultured in a 5 L fermenter, which yielded 324 U/mL chitosanases. After purification, CsnS is a cold-adapted enzyme with the highest activity at 60°C, showing 37.5% of the maximal activity at 0°C and 42.6% of the maximal activity at 10°C. It exhibited optimum activity at pH 5.8 and was stable at a pH range of 3.4–8.8. Additionally, CsnS exhibited an endo-type cleavage pattern and hydrolyzed chitosan polymers to yield disaccharides and trisaccharides as the primary reaction products. These results make CsnS a potential candidate for the industrial manufacture of COS.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF GENERAL AND APPLIED MICROBIOLOGY
·
2020
·
IF 1.442
Nengqiang Wang,Zhen Luo,Kaiqin Li,Yingcui Xu,Cheng Peng
A strain LZ1, which showed efficient asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone to enantiopure (S)-[3,5-bis(trifluoromethyl)phenyl]ethanol, which is the key intermediate for the synthesis of a receptor antagonist and antidepressant, was isolated from a soil sample. Based on its morphological, 16S rDNA sequence, and phylogenetic analysis, the strain LZ1 was identified to be Sphingomonas sp. LZ1. To our knowledge, this is the first reported case of the species Sphingomonas exhibiting stricter S-enantioselectivity and its use for the asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone. Some key reaction parameters involved in the bioreduction catalyzed by whole cells of Sphingomonas sp. LZ1 were subsequently optimized, and the optimized conditions for the synthesis of (S)-[3,5-bis(trifluoromethyl)phenyl]ethanol were determined to be as follows: phosphate buffer pH 7.5, 70 mM of 3,5-bis(trifluoromethyl) acetophenone, 30 g/L of glucose as a co-substrate, 300 g (wet weight)/L of resting cell as the biocatalyst, and a reaction for 24 h at 30°C and 180 rpm. Under the above conditions, a best yield of 94% and an excellent enantiomeric excess of 99.6% were obtained, respectively. Sphingomonas sp. LZ1 could also asymmetrically reduce a variety of prochiral ketones to their corresponding optical alcohols with excellent enantioselectivity. These results indicated that Sphingomonas sp. LZ1 had a remarkable capacity to reduce 3,5-bis(trifluoromethyl)acetophenone to its corresponding (S)-[3,5-bis(trifluoromethyl)phenyl]ethanol, and might be a new potential biocatalyst for the production of valuable chiral alcohols in industry.
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2020
·
IF 7.864
Xiaodan Ma,Bin Liang,Mengyuan Qi,Hui Yun,Ke Shi,Zhiling Li,Yuanqiang Guo,Peisheng Yan,Shuang-Jiang Liu,Aijie Wang
The chlorinated nitroaromatic antibiotic chloramphenicol (CAP) is a refractory contaminant that is widely present in various environments. However, few CAP-mineralizing bacteria have been documented, and a complete CAP catabolism pathway has yet to be identified. In this study, the bacterial strain Sphingobium sp. CAP-1 was isolated from an activated sludge sample and was shown to be capable of aerobically subsisting on CAP as the sole carbon, nitrogen, and energy source while simultaneously and efficiently degrading CAP. p-Nitrobenzoic acid (PNBA), p-nitrobenzaldehyde (PNBD), protocatechuate (PCA), and the novel side chain C3-hydroxy-oxygenated product of CAP (O-CAP) were identified during CAP degradation. Strain CAP-1 was able to convert O-CAP to intermediate product PNBA. The putative functional genes associated with PNBA catabolism into the tricarboxylic acid cycle via PCA and floc formation were also identified by genome sequencing and comparative proteome analysis. A complete pathway for CAP catabolism was proposed. The discovery of a novel CAP oxidation/detoxification process and a complete pathway for CAP catabolism enriches the fundamental understanding of the bacterial catabolism of antibiotics, providing new insights into the microbial-mediated fate, transformation, and resistance risk of CAP in the environment. The molecular basis of CAP catabolism and floc formation in strain CAP-1 also offers theoretical guidance for the enhanced bioremediation of CAP-containing environments.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Chao Gao,Yan-Hua Zeng,Cheng-Yong Li,Ling Li,Zhong-Hua Cai,Jin Zhou
Microbial degradation is an effective approach for the removal of Bisphenol A (BPA). During the biodegradation process, quorum sensing (QS) is a phenomenon that enables bacteria to coordinate collective behaviors based on cell density-dependent chemical signals. However, whether the degradation of BPA can be facilitated by this QS system (such as acyl-homoserine lactone, AHL) is unclear. To answer this question, the bifunctional Sphingonomas sp. strain YK5 that had BPA-degrading and AHL-producing properties was used. Biochemical analysis revealed that this bacterial strain mainly produced C8-HSL signals. Gene knockout experiments indicated that the AHL-system ( LuxI1/LuxI2 ) was required for efficient BPA degradation. RT-PCR analyses revealed that the AHL system positively regulated the relative expression of genes ( bisdA , CYP450 , hapA , ligAB , and proB ) involved in BPA degradation. Given that AHL signaling may be a common trait among BPA-degrading microorganisms and AHL system can regulate the degradation activity, manipulation of this system may be a valuable strategy to control BPA biodegradation.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2021
·
IF 4.952
Lei Zhang,Lingli Zhong,Juying Wang,Yuqiang Zhao,Yiwei Zhang,Yitong Zheng,Weiliang Dong,Xianfeng Ye,Yan Huang,Zhoukun Li,Zhongli Cui
The process of raw starch conversion has attracted extensive attention in recent years due to its high energy conversion efficiency and saving of operational costs. In this study, extensive hydrolysis of raw starch by α-amylase AmyM from Corallococcus sp. EGB was investigated with robust substrate and products tolerance. AmyM showed broad substrate specificity toward raw starches with different types, and kept active and stable over a wide range of temperatures (30–70 °C) and pH values (5.0–9.0) and recycling. The V max values of AmyM towards wheat and corn raw starch were 1111 and 741 μmol/min/mg without depending on Ca 2+ , respectively. SEM analysis showed that AmyM hydrolysis results in the formation of porous and creviced surfaces around the starch granules peripheries. The cost-effective conversion of raw starch for the production of malto-oligosaccharides (MOSs) was identified. AmyM achieved high hydrolysis degree of 90% for 30% wheat and corn raw starch after 20 h at 45 °C with 5 U per mg of raw starch, resulting in formation of 70% MOSs and 30% dextrin. During this process, maltose (G2), maltotriose (G3) and maltotetraose (G4) were produced synchronously with G9 and G11, indicating the potential application in enzymatic conversion of raw starch under low temperature.
✓ 已验证
DOI
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 3.978
Shuiquan Chen,Meng Zang,Lin Li,Juntao Chen,Qiyou Liu,Xiwen Feng,Shuo Sun,Chuanwei Zang,Chaocheng Zhao
Biodesulfurization is a promising, environmentally friendly method to desulfurize the organosulfur compounds in crude oils through the highly selective cleavage of carbon-sulfur bonds under mild reaction conditions. In this study, the behavior of a hydrophobic bacterium, Gordonia sp. SC-10, was evaluated in the presence of diesel oils. The biodesulfurization pathways, bacterium hydrophobicity , and cell ultrastructure were investigated, and the capability of strain SC-10 to desulfurize diesel oil was also studied. The results showed that strain SC-10 can desulfurize organosulfur compounds through sulfur-specific desulfurization pathways by producing corresponding hydroxylated products in oil-water polyphasic systems. Mycolic acids consisting of 47 and 58 carbon atoms chains were produced on the cell surface, and inclusion bodies were produced in the cells, both of which may improve the bioavailability of the substrates, thereby enhancing its adaptability to oil-water polyphasic systems. To our knowledge, this is the first report of intracellular inclusion body formation during biodesulfurization. Strain SC-10 also exhibited broad substrate specificity towards organosulfur compounds and effectively desulfurized diesel oils. The sulfur content in real-life diesel oil was reduced from 167.7 mg/L to 19.7 mg/L, with 88.3% of sulfur removed after five days of biodesulfurization. This study showed that Gordonia sp. SC-10 can be effectively used for the biodesulfurization of diesel oils.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Zhang Yajuan,Duan Yajuan,Zhong Lingli,Li Zhoukun,Cui Zhongli,Huang Yan
The asymmetric reduction of prochiral ketones is a promising process for synthesis of optically active alcohols. The aldo-keto reductase (AKR) is an attractive candidate of biocatalyst, due to its high enantioselectivity and environmentally friendly reaction conditions. In this work, nine putative AKR encoding genes from Corallococcus sp. EGB were cloned and expressed in Escherichia coli . Of these produced enzymes (CoAKRs), CoAKR7 exhibited reductive activity to various ketones and ketoesters, especially very high activity toward ethyl 4-chloro-3-oxobutanoate (COBE) with NADPH as the coenzyme. The CoAKR7 was optimally active at pH 7.0 and 50 °C. The apparent K m and V max for COBE was 14.18 U/mg and 0.269 mM, respectively. Moreover, CoAKR7 catalyzed an anti-Prelog reduction of COBE to ( S )-ethyl-4-chloro-3-hydroxybutanoate (CHBE) with e.e. >99%. Enzyme-substrate-cofactor docking analysis elucidated the molecular mechanism of the substrate stereospecificity, providing basis for protein engineering of these enzymes for applications in the synthesis of valuable chemicals.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）