Marine Drugs
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2021
·Vol. 19
·期 11
·596
·
IF 5.118
Lin-Lin Zhang,Xiao-Hua Jiang,Xin-Feng Xiao,Wen-Xiu Zhang,Yi-Qian Shi,Zhi-Peng Wang,Hai-Xiang Zhou
(1) Background: Chitooligosaccharides (COS) have numerous applications due to their excellent properties. Chitosan hydrolysis using chitosanases has been proposed as an advisable method for COS preparation. Although many chitosanases from various sources have been identified, the cold-adapted ones with high stability are still rather rare but required. (2) Methods: A novel chitosanase named CsnY from marine bacteriumRenibacteriumsp. Y82 was expressed inEscherichia coli, following sequence analysis. Then, the characterizations of recombinant CsnY purified through Ni–NTA affinity chromatography were conducted, including effects of pH and temperature, effects of metal ions and chemicals, and final product analysis. (3) Results: The GH46 family chitosanase CsnY possessed promising thermostability at broad temperature range (0–50 °C), and with optimal activity at 40 °C and pH 6.0, especially showing relatively high activity (over 80% of its maximum activity) at low temperatures (20–30 °C), which demonstrated the cold-adapted property. Common metal ions or chemicals had no obvious effect on CsnY except Mn2+and Co2+. Finally, CsnY was determined to be an endo-type chitosanase generating chitodisaccharides and -trisaccharides as main products, whose total concentration reached 56.74 mM within 2 h against 2% (w/v) initial chitosan substrate. (4) Conclusions: The results suggest the cold-adapted CsnY with favorable stability has desirable potential for the industrial production of COS.Keywords:chitosanase;cold adaptation;chitooligosaccharide;Renibacteriumsp.
研究领域:
生物化学
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生物技术
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海洋生物学
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Zhen Qin,Qiming Chen,Si Lin,Sa Luo,Yongjun Qiu,Liming Zhao
Chitooligosaccharide is widely used as a functional food additive and a valuable pharmacological agent. The transformation of chitinous biomass into valuable bioactive chitooligosaccharides is one of the most exciting applications of chitosanase. A novel glycoside hydrolase (GH) family 46 chitosanase (GsCsn46A) from rhizobacterium Gynuella sunshinyii was cloned and heterologously expressed in Escherichia coli . GsCsn46A showed maximal activity at pH 5.5 and 30 °C. GsCsn46A featured remarkable cold-adapted property, which controllably hydrolyzed chitosan to three types of chitooligosaccharides at the mild reaction condition (reaction condition: pH 5.5 at 30 °C; method for stopping the reaction: 50 °C for 30 min). The yields of three types of chitooligosaccharides products (degree of polymerization (DP): 2–7, 2–5 and 2–3) were 70.9%, 87.1% and 94.6% respectively. This novel cold-adapted chitosanase provides a cleaner production process for the controllable preparation of chitooligosaccharides with the specific DP.
研究领域:
生物化学
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酶工程
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食品科学
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DOI
PubMed
高影响因子
Frontiers of Environmental Science & Engineering
·
2017
·Vol. 11
·期 3
·1-8
·
IF 1.716
Shi Yuanyuan,Kong Deyang,Liu Jiayang,Lu Junhe,Yin Xiaoming,Zhou Quansuo
This work investigated the transformation of triclosan (TCS) by the laccase produced by a pathogen isolated from rotten tomato. The pathogen was characterized as Botrytis sp. FQ, belonging to subphylum Deuteromycotina . The laccase exhibited cold-adaptation with relatively high activity at 20°C. The laccase could effectively transform TCS. Approximately 62% TCS could be removed at dose of 1.0 unit∙mL –1 in 120 min. The reaction rate appeared to be pseudo-first-order to the concentration of the substrate, suggesting the laccase activity remained stable during the reaction. Transformation products of TCS were analyzed by mass spectrometry and it was revealed that TCS dimers were formed via radical coupling pathways. During this process, laccase catalyzed oxidation of TCS to form a radical intermediate is the rate limiting step. However, this step can be reversed by humic acid. Overall, the laccase showed great potential in the treatment of phenolic contaminants. Since laccase is widely presented in natural environment, this study also revealed an important pathway involved in the transformation of phenolic contaminants in the environment.
研究领域:
环境科学
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微生物学
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DOI
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.
研究领域:
海洋生物技术
·
酶学
·
生物催化
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工业微生物学
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2017
·
IF 3.154
Shan Zhou,Jinlong Song,Weiwei Dong,Yingchun Mu,Qi Zhang,Ziwen Fan,Yanwei Wang,Delong Kong,Yiqing Zhou,Xu Jiang,Bin Zhao,Gang Han,Zhiyong Ruan
Nicosulfuron is a common environmental pollutant, posing a great threat to aquatic systems and causing significant damage to crops. This study reported a cold-adapted strain Oceanisphaera psychrotolerans LAM-WHM-ZC, which efficiently degrades nicosulfuron over a wide range of temperatures (5 to 40 °C). The Box–Behnken design method was used to optimize the degradation conditions. O. psychrotolerans LAM-WHM-ZC can degrade 92.4% and 74.6% of initially supplemented 100 mg/L nicosulfuron under the optimum and low temperature of 18.1 and 5 °C, respectively, within 7 days. O. psychrotolerans LAM-WHM-ZC was found to be highly efficient in degrading cinosulfuron, chlorsulfuron, rimsulfuron, bensulfuron methyl, and ethametsulfuron methyl. Metabolites from nicosulfuron degradation were identified by UPLC-MS, and a possible degradation pathway was proposed. Furthermore, O. psychrotolerans LAM-WHM-ZC can also degrade nicosulfuron in soil; 78.6% and 67.4% of the initial nicosulfuron supplemented at 50 mg/kg were removed at 18.1 and 5 °C, respectively, within 15 days.
研究领域:
环境科学
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微生物学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Ailin Zhang,Yanhua Hou,Quanfu Wang,Yatong Wang
Biotreatment of polyethylene (PE) waste is an emerging topic in environmental remediation; in particular, the degrading enzymes requires further exploration. This study described a novel cold-adapted laccase (PsLAC) from an Antarctic psychrophile and characterized its PE-degradation ability. Homology modeling revealed that PsLAC possessed a typical bacterial laccase catalytic structure and unique cold adaptation structural characteristics such as few hydrogen bonds . Recombinant PsLAC (rPsLAC) retained 54.3% residual activity at 0 ℃ and presented increased K m values at low temperatures and a relatively high k cat value (42.65 s −1 ). Collectively, these factors help resist cold stress. rPsLAC possessed substantial salt tolerance at 1.5 M NaCl, with 119.80% activity, and Cu 2+ enhanced its activity to 127.10%. PE-degradation experiments indicated that 13.2% weight was lost, and the water contact angle was decreased to 74.6°. Polar functional groups such as carbonyl and carboxyl groups on PE surface were detected in Fourier transform infrared spectroscopy ; X-ray diffraction exhibited that crystallinity reduced by 25%. Enormous damage to PE surface and interior was observed via scanning electron microscopy. Overall, PsLAC, with its unique cold-adapted catalytic structure and biochemical characteristics, could supplement the diversity of sources and properties of bacterial laccases and ensure PE-degradation with a novel cold-adapted enzyme resource.
研究领域:
环境科学
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微生物学
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生物技术
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DOI
PubMed
高影响因子
JOURNAL OF SURFACTANTS AND DETERGENTS
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2024
·
IF 1.6
Qinzhou Cai,Huifang Zhang,Bingshan Zhao,Lei Ren,Yonghua Wang,Fanghua Wang
Cold-adapted, alkali-stable lipases with surfactant tolerance are highly sought after in the detergent industry. In this study, we recombinantly expressed and characterized a novel lipase from Marinobacter nanhaiticus (MNL). The purified MNL exhibited high stability within a temperature range of 10–30°C and pH values of 8–10, demonstrating optimal activity at 20°C and pH 8. MNL has a preference for substrates with medium chains with the best activity being 3768.6 U/mg using p -nitrophenyl decanoate as a substrate. Remarkably, MNL showed enhanced enzymatic activity in the presence of ionic surfactants and displayed notable resilience when exposed to proteases. Washing performance analysis further revealed MNL's high proficiency in removing oil-based stains from fabrics. Collectively, these results suggest that MNL holds significant promise as a valuable component in laundry detergent formulations.
研究领域:
生物化学
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工业微生物学
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DOI
高影响因子
JOURNAL OF BIOLOGICAL CHEMISTRY
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2021
·Vol. 297
·期 1
·
IF 5.157
Yi Zhang,Hai-Tao Ding,Wen-Xin Jiang,Xia Zhang,Hai-Yan Cao,Jing-Ping Wang,Chun-Yang Li,Feng Huang,Xi-Ying Zhang,Xiu-Lan Chen,Yu-Zhong Zhang,Ping-Yi Li
SGNH-type acetyl xylan esterases (AcXEs) play important roles in marine and terrestrial xylan degradation, which are necessary for removing acetyl side groups from xylan. However, only a few cold-adapted AcXEs have been reported, and the underlying mechanisms for their cold adaptation are still unknown because of the lack of structural information. Here, a cold-adapted AcXE, AlAXEase, from the Arctic marine bacterium Arcticibacterium luteifluviistationis SM1504T was characterized. AlAXEase could deacetylate xylooligosaccharides and xylan, which, together with its homologs, indicates a novel SGNH-type carbohydrate esterase family. AlAXEase showed the highest activity at 30 °C and retained over 70% activity at 0 °C but had unusual thermostability with a Tm value of 56 °C. To explain the cold adaption mechanism of AlAXEase, we next solved its crystal structure. AlAXEase has similar noncovalent stabilizing interactions to its mesophilic counterpart at the monomer level and forms stable tetramers in solutions, which may explain its high thermostability. However, a long loop containing the catalytic residues Asp200 and His203 in AlAXEase was found to be flexible because of the reduced stabilizing hydrophobic interactions and increased destabilizing asparagine and lysine residues, leading to a highly flexible active site. Structural and enzyme kinetic analyses combined with molecular dynamics simulations at different temperatures revealed that the flexible catalytic loop contributes to the cold adaptation of AlAXEase by modulating the distance between the catalytic His203 in this loop and the nucleophilic Ser32. This study reveals a new cold adaption strategy adopted by the thermostable AlAXEase, shedding light on the cold adaption mechanisms of AcXEs.
研究领域:
生物化学
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结构生物学
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酶学
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DOI
PubMed
高影响因子
JOURNAL OF FOOD ENGINEERING
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2025
·
IF 5.8
Caiyun Wang,Changhao Liu,Zhicen Liu,Han Xu,Yue Zhang
Sugar fatty acid esters, serving as multifunctional biosurfactants, are extensively utilized in food formulations for emulsification, foam stabilization, and microbial preservation. Enzymatic transesterification using lipases offers distinct advantages over chemical synthesis, including mild reaction conditions and reduced energy consumption. In this study, we engineered a cold-adapted lipase (Lip) through lid domain truncation and mutation, yielding the optimized variant Lip-8 to alleviate substrate channel steric hindrance, coupled with tannic acid-modified magnetic nanoflowers (TA-MNFs) via a one-pot immobilization strategy to create Lip-8/TA-MNFs. This immobilized enzyme demonstrated significantly enhanced catalytic performance, achieving a 12.91-fold activity increase compared to free lipase. Under optimized conditions (40 °C, 36 h), the system synthesized fructose laurate esters with 93.07 % conversion efficiency. Structural characterization confirmed the predominant formation of mono- and di-esters, which exhibit dual surfactant and emulsifying properties suitable for food-grade applications.
研究领域:
食品科学
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生物化学
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纳米技术
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Mengyao Hao,JiaXin Yao,Jianxiong Chen,Rui Zhu,Zhenghua Gu,Yu Xin,Liang Zhang
Laccase (EC 1.10.3.2), as eco-friendly biocatalysts, holds immense potential for sustainable applications across various environmental and industrial sectors. Despite the growing interest, the exploration of cold-adapted laccases, especially their unique properties and applicability, remains limited. In this study, we have isolated, cloned, expressed, and purified a novel laccase from Peribacillus simplex (GenBank: PP430751), which was derived from permafrost layer. The recombinant laccase (PsLac) exhibited optimal activity at 30 °C and a pH optimum of 3.5. Remarkably, PsLac exhibited remarkable stability in the presence of organic solvents, with its enzyme activity increasing by 20 % after being incubated in a 30 % trichloromethane solution for 12 h, compared to its initial activity. Furthermore, the enzyme preserved 100 % of its activity after undergoing eight freeze-thaw cycles. Notably, the catalytic center of PsLac contains Zn 2+ instead of the typically observed Cu 2+ found in other laccases, and metal-ion substitution experiments raised the catalytic efficiency to 3-fold when Zn 2+ was replaced with Fe 2+ . Additionally, PsLac has demonstrated a proficient ability to degrade phenolic pollutants, such as hydroquinone, even at a low temperature of 16 °C, positioning it as a promising candidate for environmental bioremediation and contributing to cleaner production processes.
研究领域:
环境科学
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生物化学
·
酶学
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
·
2020
·
IF 4.187
Yanbo Wang,Feifei Wang,Xiaoshuang Zhang,Congnan Cen,Linglin Fu
Shewanella baltica is the specific spoilage microorganism of Pseudosciaena crocea during low-temperature storage. Exploring the correlation between cold adaptability and spoilage potential may provide a new perspective for prolonging shelf life of aquatic products. In the present study, we investigated the synthesis pathway of unsaturated fatty acid (UFA) responsible for regulating cold adaptability in Shewanella baltica and its effect on spoilage potential. FabR and FadR, as key regulators of membrane unsaturated fatty acids synthesis pathway, were identified in S. baltica . FabR was significantly down-regulated at 4 °C compared to at 30 °C, yet FadR displayed the opposite results. By overexpressing fabR and fadR genes at 4 °C, we found that FabR and FadR had negative and positive effects on UFA content and membrane fluidity as well as spoilage potential, respectively. These data indicated that FabR and FadR functioned collectively to increase the membrane fluidity for better cold adaptability at low temperature, resulting in the maintenance of spoilage potential of S. baltica .
研究领域:
微生物学
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食品科学
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分子生物学
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2020
·
IF 5.162
Yani Wang,Zhen Qin,Liqiang Fan,Liming Zhao
Chitooligosaccharides (COS) is a kind of functional carbohydrates with great application potential as its various biological functions in food, cosmetics, and pharmaceutical fields. Exploring the relationship between structure and function of chitosanase is essential for the controllable preparation of chitooligosaccharides with the specific degree of polymerization (DP). GsCsn46A is a cold-adapted glycosyl hydrolase (GH) family 46 chitosanase with application potential for the controllable preparation of chitooligosaccharides. Here, we present two complex structures with substrate chitopentaose and chitotetraose of GsCsn46A, respectively. The overall structure of GsCsn46A contains nine α-helices and two β-strands that folds into two globular domains with the substrate between them. The unique binding positions of both chitopentaose and chitotetraose revealed two novel sugar residues in the negatively-numbered subsites of GH family 46 chitosanases. The structure–function analysis of GsCsn46A uncovers the substrate binding and catalysis mechanism of GH family 46 chitosanases. Structural basis mutagenesis in GsCsn46A indicated that altering interactions near +3 subsite would help produce hydrolysis products with higher DP. Specifically, the mutant N21W of GsCsn46A nearly eliminated the ability of hydrolyzing chitotetraose after long-time degradation.
研究领域:
生物化学
·
酶学
·
结构生物学
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生物技术
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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）