PROTEIN EXPRESSION AND PURIFICATION
·
2015
·
IF 1.695
Jian-yong Zheng,Jian Wang,Sha-sha Zhou,Xiao-jun Li,Xiang-xian Ying,Zhao Wang
Esterases (EC 3.1.1.X) have been used as biocatalysts due to their good stability, high chemo-, regio- and stereoselectivity. In our previous studies, Bacillus megaterium WZ009 harboring esterase displayed the unique capability to convert ( S )-4-Chloro-3-hydroxyethylbutyrate (CHBE) in the racemate to ( S )-3-hydroxy-γ-butyrolactone (HL) through stereoselective hydrolysis, dechlorination, and lactonization. The remaining ( R )-CHBE and formed ( S )-HL could be obtained in a one-pot enzymatic reaction. An esterase from B. megaterium WZ009 was purified and was found to have 466 encoded amino acids and an apparent molecular mass of 55 kDa. The purified esterase exhibited maximal activity at a temperature of 25 °C and at a pH of 11.5 towards 100 mM CHBE. When the stereoselective biocatalysis of rac -CHBE was performed using the recombinant Escherichia coli BL21 (DH3) cells harboring the esterase, the catalytic activity increased by 20-fold compared with the original strain B. megaterium WZ009. With the addition of activated carbon (62 g/L) in the reaction system, the conversion was increased from 39% to 45% at a substrate concentration of 750 mM. Another remarkable advantage is that both of the obtained residual ( R )-CHBE and the formed ( S )-HL had high optical purities ( e.e. s > 99.9%, e.e. p > 99.9%), thereby making this esterase a usable biocatalyst for industrial application.
研究领域:
生物化学
·
分子生物学
·
工业酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2019
·Vol. 188
·期 4
·965-976
·
IF 2.14
Wang Huanhong,Qin Yi,Li Baocai,Xiang Cheng,Dai Weifeng,Jiao Shiyun,Zhang Mi
The montan resin (MR) is a solid waste produced during the industrial process of refined montan wax from lignite, and usually disposed by landfill and incineration, which easily cause environmental pollution and resource waste. Based its physicochemical properties, our study attempted to modify MR by Bacillus benzoevorans to achieve ecological utilization of MR. As results, the weight loss rate of MR, expressed as modification degree, was found to increase with the increase of B. benzoevorans -incubated time. The apparent oil–water partition coefficient ( K ow), used to evaluate the improvement on hydrophilicity of MR, significantly increased ( P < 0.01) after modification. IR analysis showed the functional groups of –OH and C=O in modified MR were more than those in MR. Meanwhile, comparison of the chemical changes between MR and modified MR by relatively quantitative analysis of gas chromatography–mass spectrometry (GC-MS) revealed that the content of some chemical components in the latter decreased, and the newly appeared chemical components all had more oxygen-containing functional groups. The bioactivity of the modified MR in agricultural application was evaluated regarding germination and seedling growth of maize seed preliminarly. Compared with the original MR-treated group, the modified MR showed an obvious effect on promoting the growth and germination of maize .
研究领域:
环境科学
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微生物学
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农业科学
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产品关联
DOI
PubMed
高影响因子
PLoS One
·
2014
·Vol. 9
·期 6
·e100731
·
IF 3.534
Ke Xu,Ping Xu
Lactic acid is an important chemical with various industrial applications, and it can be efficiently produced by fermentation, in which Bacillus coagulans strains present excellent performance. Betaine can promote lactic acid fermentation as an effective osmoprotectant. Here, positive effect of betaine on fermentation by B. coagulans is revealed. Betaine could enhance lactic acid production by protecting l -LDH activity and cell growth from osmotic inhibition, especially under high glucose concentrations and with poor organic nitrogen nutrients. The fermentation with 0.05 g/L betaine could produce 17.9% more lactic acid compared to the fermentation without betaine. Beet molasses, which is rich in sucrose and betaine, was utilized in a co-feeding fermentation and raised the productivity by 22%. The efficient lactic acid fermentation by B. coagulans is thus developed by using betaine and beet molasses.
研究领域:
微生物学
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生物工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2019
·
IF 2.883
Hong Zhou,Bailin Cong,Yongqi Tian,Yu He,Huanghao Yang
Three new cyclic lipopeptides (compounds 1–3) were isolated from Bacillus sp. SY27F, which collected from the deep-sea hydrothermal vent in the Indian Ocean. The planar structures of compounds 1–3 were characterized by LC–MS, GC–MS and NMR, whereas their absolute configurations were determined by modified Marfey’s analysis and optical rotation contrast. They shared the same heptapeptide chain (N-L-Gln 1 -D-Leu 2 -L-Leu 3 -L-Val 4 -L-Asp 5 -D-Leu 6 -L-Ile 7 -C), differing only by the length of the fatty acid chain. Compounds 1–3 displayed significant cytotoxic activity against DU145, MCF-7 and HepG2 cancer cell lines with IC 50 values of 96.8–190.7 nM and moderate to weak cytotoxicity against A549, HeLa and HT1080, with IC 50 values of 9.3–43.2 μM, respectively. However, none of the three compounds showed any antibacterial activity against Escherichia coli, Staphylococcus aureus and Monilia albicans .
研究领域:
微生物学
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药物化学
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海洋生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF FOOD PROCESSING AND PRESERVATION
·
2025
·Vol. 2025
·期 1
·6298724
·
IF 2.5
Niuniu Bai,Jianlin He,Bihong Hong,Zelong Wu,Liping Wang,Zongze Shao
Background: Traditional fish sauce is made from fish that have been coated in 30%–40% sea salt and fermented for up to 2 years. The preparation requires a long time, and the fish source contains considerable biogenic amines. In this report, by measuring the growth curve and identifying the intracellular enzyme and the activity of protease, B. zhangzhouensis with the highest activity of protease production was selected from eight strains, which were applied to the fermentation process of fish sauce. Results: Optimized by response surface methodology, the content of amino nitrogen was taken as the response value, and the best fermentation conditions were 4.15% inocula, pH 9.13, and 36.3°C. Under the optimized conditions, fish sauce samples were obtained by fermentation with B. zhangzhouensis for 15 h, 3 days, 7 days, 15 days, and 30 days, respectively. The contents of amino nitrogen, total nitrogen, biogenic amine, and various flavor substances were determined and compared with the traditional 2-year-fermented fish sauce. As a result, the 7-day-fermented fish sauce using B. zhangzhouensis had a similar composition of flavor substances to traditional fish sauce, but a much lower level of biogenic amines. Conclusion: The new method of preparing fish sauce with a fermentation condition of 4.15% B. zhangzhouensis , pH 9.13, and 36.3°C can improve the production efficiency of fish sauce, and the flavor is similar to that of traditional fish sauce.
研究领域:
食品科学
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2022
·
IF 4.885
Chengchen Cai,Ming Zhang,Haiming Chen,Wenxue Chen,Weijun Chen,Qiuping Zhong
Mango juice (MJ) has high nutritional value and decent flavor. However, its aroma could be easily changed by heat treatment during processing, which affects its acceptability and quality. In this study, Bacillus subtilis -HNU-B3 that could transfer carotenoid, was obtained from orchard soil to improve the aroma of fermented mango juice (FMJ). Compared with MJ, the organic acid content of FMJ by B. subtilis -HNU-B3 was significantly changed, and the contents of succinic acid and malic acid were increased to 3.68 mg/mL and 2.04 mg/mL, respectively. Moreover, volatile compounds identified by headspace solid-phase micro-extraction gas-phase mass spectrometry in FMJ were norisoprenoid and acetoin, accounting for 51.52 % of the total volatile substances. In addition, B. subtilis -HNU-B3 fermentation significantly increased the antioxidant capacity and total phenol contents of MJ, and the activity of carotenoid cleavage dioxygenase was 188 U/L. In conclusion, the aroma of FMJ could be improved by B. subtilis -HNU-B3 through increasing the content of norisoprenoid and acetoin. Our results provide theatrical support for Bacillus subtilis to improve the aroma quality of FMJ.
研究领域:
食品科学
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微生物学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
·
2016
·
IF 2.189
Xiqian Sheng,Ming Yan,Lin Xu,Miao Wei
We identified and characterized YqiG, a novel Old Yellow Enzyme (OYE) from Bacillus subtilis str.168 , as a member of the “thermophilic-like” subfamily. It is most related to XenA from Pseudomonas putida , with 37.9% identity, but it exhibits certain differences in sequence and enzyme properties. The YqiG can reduce various activated alkenes and exhibits high temperature (60 °C for 12 h) and pH stability (pH 4.0 and 9.0 for 12 h), which indicates that it has a great potential for biocatalysis. However, it shows low tolerance toward organic solvents. Also the YqiG shows high activities towards maleimide, dimethyl maleate and acyclic ketones (55.5 U/mg, 6.22 U/mg and 2.97 U/mg, respectively). Besides, The YqiG can catalyze citral to (S)-citronellal with a low rate but high ee% (>99%).
研究领域:
生物化学
·
酶学
·
微生物学
✓ 已验证
DOI
高影响因子
Foods
·
2023
·Vol. 12
·期 18
·3350
·
IF 5.2
Yuhan Wang,Hongjuan Mo,Zhihong Hu,Bingjie Liu,Zhiqian Zhang,Yaowei Fang,Xiaoyue Hou,Shu Liu,Guang Yang
Chitooligosaccharides (COS), a high-value chitosan derivative, have many applications in food, pharmaceuticals, cosmetics and agriculture owing to their unique biological activities. Chitosanase, which catalyzes the hydrolysis of chitosan, can cleave β-1,4 linkages to produce COS. In this study, a chitosanase-producingBacillus paramycoidesBP-N07 was isolated from marine mud samples. The chitosanase enzyme (BpCSN) activity was 2648.66 ± 20.45 U/mL at 52 h and was able to effectively degrade chitosan. The molecular weight of purifiedBpCSN was approximately 37 kDa. The yield and enzyme activity ofBpCSN were 0.41 mg/mL and 8133.17 ± 47.83 U/mg, respectively. The optimum temperature and pH ofBpCSN were 50 °C and 6.0, respectively. The results of the high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC) of chitosan treated withBpCSN for 3 h showed that it is an endo-chitosanase, and the main degradation products were chitobiose, chitotriose and chitotetraose.BpCSN was used for the preparation of oligosaccharides: 1.0 mg enzyme converted 10.0 g chitosan with 2% acetic acid into oligosaccharides in 3 h at 50 °C. In summary, this paper reports thatBpCSN has wide adaptability to temperature and pH and high activity for hydrolyzing chitosan substrates. Thus,BpCSN is a chitosan decomposer that can be used for producing chitooligosaccharides industrially.Keywords:Bacillus paramycoides;chitosanase;chitosan;chitosan oligosaccharides;enzymatic properties
研究领域:
微生物学
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生物技术
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Qingshan Zhang,Xinxin Yan,Yaoli Peng
Bioleaching of effective silicon represents a crucial method for the green and efficient utilization of coal tailings (CTs). However, the influence of heavy metals present in coal tailings on this process cannot be underestimated. This study investigates the effects of five high-concentration heavy metal elements (Pb, Zn, Cu, Cr, and Ni) in CTs on the biological characteristics and leaching processes of Bacillus mucilaginosus ( B.M. ). The results indicated that varying concentrations of heavy metal elements significantly influenced the bioleaching of effective silicon by B.M. . Kinetic analysis revealed that the leaching process predominantly adhered to a chemical reaction-controlled mechanism. Changes in the functional groups, mineral composition, and morphology of the CTs surface demonstrated that chromium and nickel exerted a negligible effect on leaching effectiveness, with effective silicon concentrations of 315.71 mg/L and 322.62 mg/L, respectively. The activity of B.M. induced surface erosion of CTs, disrupting the crystal structure of silicon-bearing minerals and facilitating the conversion of silicon in quartz and kaolinite to effective silicon. In contrast, lead, zinc, and copper significantly inhibited B.M. , hindering effective erosion of CTs and resulting in lower effective silicon leaching concentrations of 129.65 mg/L, 142.68 mg/L, and 135.70 mg/L, respectively. Therefore, this study summarizes the effects of various heavy metal elements on the bioleaching of effective silicon by B.M. , providing a scientific foundation for the environmentally sustainable utilization of CTs.
研究领域:
微生物学
·
环境科学
✓ 已验证
DOI
高影响因子
ARCHIVES OF MICROBIOLOGY
·
2024
·Vol. 206
·期 3
·1-17
·
IF 2.3
Wang Ze,Zhang Wenwen,Wang Ziyan,Zhang Zhixuan,Liu Yan,Liu Songyi,Wu Qiaoli,Saiding Emilaguli,Han Jiaojiao,Zhou Jun,Xu Jiajie,Yi Xianghua,Zhang Zhen,Wang Rixin,Su Xiurong
A new strain of Bacillus velezensis NDB was isolated from Xiangshan Harbor and antibacterial test revealed antibacterial activity of this strain against 12 major pathogenic bacteria. The whole genome of the bacterium was sequenced and found to consist of a 4,214,838 bp circular chromosome and a 7410 bp circular plasmid. Furthermore, it was predicted by AntiSMASH and BAGEL4 to have 12 clusters of secondary metabolism genes for the synthesis of the inhibitors, fengycin, bacillomycin, macrolactin H, bacillaene, and difficidin, and there were also five clusters encoding potentially novel antimicrobial substances, as well as three bacteriocin biosynthesis gene clusters of amylocyclicin, ComX1, and LCI. qRT-PCR revealed significant up-regulation of antimicrobial secondary metabolite synthesis genes after 24 h of antagonism with pathogenic bacteria. Furthermore, MALDI-TOF mass spectrometry revealed that it can secrete surfactin non-ribosomal peptide synthase and polyketide synthase to exert antibacterial effects. GC-MS was used to analyze methanol extract of B. velezensis NDB, a total of 68 compounds were identified and these metabolites include 16 amino acids, 17 acids, 3 amines, 11 sugars, 11 alcohols, 1 ester, and 9 other compounds which can inhibit pathogenic bacteria by initiating the antibiotic secretion pathway. A comparative genomic analysis of gene families showed that the specificity of B. velezensis NDB was mainly reflected in environmental adaptability. Overall, this research on B. velezensis NDB provides the basis for elucidating its biocontrol effect and promotes its future application as a probiotic.
研究领域:
微生物学
·
分子生物学
·
生物技术
✓ 已验证
DOI
PubMed
高影响因子
FEBS Open Bio
·
2020
·Vol. 10
·期 12
·2733-2739
·
IF 2.231
Sai-sai Ding,Jin-peng Zhu,Yang Wang,Bin Wu,Zongpei Zhao
In the paper industry, chlorine is often used to treat the pulp for bleaching. After pulping, a large amount of xylan is present in the fiber. Xylanase can be used to degrade xylan in an eco-friendly process called biobleaching, which can help minimize the usage of chlorine in the delignification process. However, a bottleneck in the adoption of biobleaching is the cost of xylanase and the requirement that xylanase be active and stable at extreme conditions. Here, we investigated whether using sodium alginate beads to immobilize an extracellular xylanase from Bacillus subtilis (Lucky9) can reduce the potential cost of enzyme usage. The optimal pH and the activity of the immobilized enzyme were increased at optimal temperature compared with the free enzyme. In addition, immobilized xylanase was shown to be more stable than free xylanase. The results of this study suggest that the immobilized xylanase has potential applications in the biobleaching industry.
研究领域:
生物技术
·
酶工程
·
制浆造纸工业
✓ 已验证
DOI
PubMed
高影响因子
FEMS MICROBIOLOGY LETTERS
·
2018
·Vol. 365
·期 7
·
IF 1.735
Qian Bingjun,Yin Lirong,Yao Xiaomin,Zhong Yaoguang,Gui Juan,Lu Feifeng,Zhang Fuming,Zhang Jianhua
The saponins, as components of tea seed meal, are undesirable hemolytic components and should be degraded for reducing their hemolytic activity in order to be used in animal feed. In this study, β-glucuronidase was verified to be a potent hydrolase of tea seed saponins to reduce their hemolytic activity and a β-glucuronidase-producing Lactobacillus crustorum strain was screened from raw bovine milk. Next, solid-state fermentation with the isolated L. crustorum and a Bacillus subtilis natto strain, which can produce cellulase and hence improve the fermentation performance of tea seed meal, was carried out for detoxification of tea seed meal. The 50% hemolytic dosage (HD50) value of tea seed saponins was increased from 6.69 to 27.43 μg mL−1. The results of LC–MS analysis showed that the percentage of saponin aglycones increased from 30.95 to 84.25% after the fermentation. According to the roles of sugar moieties in hemolytic activity, and the enzymatic hydrolysis characteristics of β-glucuronidase, the degradation of tea seed saponins from glucosides to aglycones may contribute to the reduction of hemolytic activity. Therefore, tea seed meal may be used as animal feed after fermentation with the tested saponin-degrading microbial strains.
研究领域:
微生物学
·
动物营养学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）