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1.
林俨  刘玉军  汪婷  陈名君 《微生物学通报》2021,48(12):4555-4563
[背景] 粉棒束孢是自然环境中常见的一种昆虫病原真菌,全球广泛分布且寄主多样。然而,棒束孢属许多种形态学特征相似,仅根据经典形态学鉴定容易出现错乱现象。长期以来依据形态特征鉴定为粉棒束孢的菌株,其准确的分类地位出现了越来越多的争议。最近,该属起源被确定是多系发生的。[目的] 明确粉棒束孢的分类沿革并探究先前被鉴定为粉棒束孢菌株的准确分类地位。[方法] 选取6株先前被鉴定为粉棒束孢的菌株,对其进行经典形态观察,并扩增5个基因位点(nrSSU、nrLSU、TEF、RPB1和RPB2)的基因序列,进行多基因分子系统发育学分析。[结果] 通过查阅文献和实验研究,明确了粉棒束孢分类研究的历史沿革;供试的6株不同来源的菌株与粉棒束孢模式种亲缘关系较远,而与新成立的组合种Samsoniella hepiali完全一致。[结论] 利用经典形态学特征和构建5个基因系统发育树,重新修订6株类棒束孢菌株的正确分类地位为Samsoniella hepiali。为该类昆虫病原真菌正确分类提供合理的方法,也为开发和利用该类菌株提供科学的指导。  相似文献   

2.
【背景】目前利用酵母表达系统已鉴定了多种物种中的Δ6脂肪酸脱饱和酶(FADS6)。由于FADS6是一种具有多个跨膜螺旋的膜蛋白,使得其大量表达和纯化具有挑战性。【目的】探索FADS6的高效表达策略,研究纯化标签添加的位置对高山被孢霉FADS6I (Ma FADS6I)重组表达效率的影响。【方法】在毕赤酵母表达载体中插入串联亲和标签HRV 3C-Protein A-His,利用改造后的载体构建带有N端或C端标签的Ma FADS6I表达载体;通过电转化获得毕赤酵母重组表达菌株;利用斑点印迹杂交(DotBlot)、聚丙烯酰胺凝胶电泳(SDS-PolyacrylamideGelElectrophoresis,SDS-PAGE)和免疫印迹(Western Blot)分析重组蛋白的表达水平,并利用气相色谱-质谱(Gas Chromatography-Mass Spectrometry,GC-MS)分析检测Ma FADS6I催化生成的脂肪酸。【结果】通过大量的毕赤酵母转化子筛选,最终获得高效表达Ma FADS6I的毕赤酵母重组菌,证实各转化子的表达具有差异性,Ma FADS6I的C端带有纯化标签较N端更有利于表达。【结论】在Ma FADS6I的C端添加纯化标签比在N端添加更有利于该蛋白在酵母系统中的表达以及底物的转化,为进一步探究FADS6高效表达和结构功能奠定了基础。  相似文献   

3.
Here we determined the in vitro inhibitory effects of 5-(2-hydroxyethyl)-3,4-dimethylthiazolium iodide (1), 3-Benzyl-5-(2-hydroxyethyl)-4-methylthiazolium chloride (2) and thiamine (3) on human erythrocyte carbonic anhydrase I, II isozymes (hCA I and hCA II) and secreted isoenzyme CA VI. KI values ranged from 0.38 to 2.27 µM for hCA I, 0.085 to 0.784 µM for hCA II and 0.062 to 0.593 µM for hCA VI, respectively. The compounds displayed relatively strong actions on hCA II, in the same range as the clinically used sulfonamidesethoxzolamide, zonisamide and acetazolamide.  相似文献   

4.
【目的】从菌株Streptomyces albus DSM 41398的发酵产物中发掘结构多样的由I型聚酮合酶催化形成的化合物,以期找到具有新颖结构或强生物活性的化合物。在结构鉴定的基础上,对其生物合成途径进行分析。【方法】利用HPLC分析方法,通过系统比较野生型菌株S.albus DSM 41398与I型聚酮合酶编码基因簇失活突变株的发酵产物差异,实现目标化合物的定向分离。然后,利用~1H-和~(13)C-NMR以及HR-ESI-MS进行化合物的结构鉴定。最后,利用生物信息学等方法对化合物的生物合成途径进行推测和分析。【结果】从5 L的S.albus DSM 41398发酵产物中,分离得到了2个具有抗肿瘤活性的聚酮类化合物放线吡喃酮和洋橄榄菌素,分别定位了它们的生物合成基因簇,并分别对其生物合成途径进行了推导。其中,放线吡喃酮的生物合成基因簇为首次报道。【结论】本研究一方面为基因组发掘S.albus DSM 41398中其他由I型聚酮合酶催化形成的化合物提供参考,另一方面也为相关化合物的结构修饰改造奠定了良好的基础。  相似文献   

5.
Summary The fungus Aspergillus terreus Thorn var. terreus isolated from an Ecuador soil sample was cultured in liquid and solid media and yielded three main metabolites identified as terreic acid (1), butyrolactone I (2) and lovastatin (3). The natural products as well as three synthetic butyrolactone I derivatives were assessed for antimicrobial activity against Gram-positive and Gram-negative bacteria and fungi as well as for seed germination and seedling growth. Furthermore, the compounds were assessed as inhibitors towards the enzymes acetylcholinesterase, β-glucosidase, and β-glucuronidase. Terreic acid, butyrolactone I, butyrolactone 4′,4′′-diacetate (2.1), and 3′-(3-methylbutyl)-butyrolactone II (2.2) were active towards the phytopathogenic bacteria Erwinia carotovora with IC50 of 5 and 4–18 μg/ml, respectively. Under the same experimental conditions, the IC50 of streptomycin was 1.9 μg/ml. 3′-(3-Methylbutyl)-butyrolactone II was moderately active against Pseudomonas syringae and Botrytis cinerea with IC50 of 21μg/ml and MIC of 15.6 μg/ml, respectively. Butyrolactone I also inhibited germination of the dicot Lactuca sativa with an IC50 of 5 × 10−5 M. The IC50 of reference herbicide acetochlor was 1 × 10−5 M. The effect of 2.2 and 2.3, known as butyrolactone III on Panicum millaceum germination and growth was stronger than that of 2 and 2.1. Reduction of the double bond in the isoprenyl side chain of butyrolactone I increased the antibacterial effect against E. carotovora as well as acetylation. To our best knowledge, this is the first report on the antibacterial effect of butyrolactone derivatives towards Erwinia carotovora and the phytopathogenic fungus Botrytis cinerea. The butyrolactone I derivative 2.2 presented a moderate inhibitory effect against the enzyme acetylcholinesterase with an IC50 of 47 μg/ml. Under the same experimental conditions, the reference inhibitor galanthamine had an IC50 of 3 μg/ml.  相似文献   

6.
Objectives: The role of aryl hydrocarbon receptor (AhR) in carcinogenesis has been studied recently. Indole-3-carbinol (I3C) is an AhR agonist and a potential anticancer agent. Here, we investigated the effects of I3C on cell cycle progression and apoptosis through activation of AhR on THP-1 acute myeloid leukemia (AML) cell line.

Methods: MTT viability assay was used to measure the cytotoxic effects of I3C on THP-1 cells. Apoptosis and cell cycle assays were investigated using flow cytometry. Real time RT-PCR was conducted to measure the alterations in the expression of AhR gene, key genes associated with AhR activation (IL1β and CYP1A1) and major genes involved in cell cycle regulation and apoptosis including P27, P21, CDK2, P53, BCL2 and FasR.

Results: Our findings revealed that I3C inhibits the proliferation of THP-1 cells in a dose- and time-dependent manner with minimal toxicity over normal monocytes. The AhR target genes (CYP1A1, IL1β) were overexpressed upon I3C treatment (p?p?p?p?p?p?p?p?Conclusions: I3C could exert its antileukemic effects through AhR activation which is associated with programed cell death and G1 cell cycle arrest in a dose- and time-dependent manner. Therefore, AhR could be targeted as a novel treatment possibility in AML.  相似文献   

7.
Two novel proton transfer compounds were prepared between 2,4-dichloro-5-sulphamoylbenzoic acid (lasamide) (Hsba) and ethylenediamine (en), namely ethane-1,2-diaminium 2,4-dichloro-5-sulphamoylbenzoate (1), and also between Hsba and 2-amino-3-methylpyridine (2-amino-3-picoline) (amp), namely 2-amino-3-methylpyridinium 2,4-dichloro-5-sulphamoylbenzoate (2). All these were characterised by elemental, spectral (IR and UV-vis), thermal analyses, and single crystal X-ray diffraction studies. Compounds 1 and 2 crystallised in the P-1 and P21/c space groups, respectively. Intermolecular non-covalent interactions, such as ion pairing, hydrogen bonding, and π-π stacking were observed for these ionic compounds. The free ligands Hsba, en and amp, the products 1 and 2, and acetazolamide (AAZ) as the control compound, were also evaluated for their in vitro inhibitor effects on the human carbonic anhydrase isoenzymes (hCA I and hCA II) purified from erythrocyte cells by affinity chromatography for their hydratase and esterase activities. The half maximal inhibitory concentration (IC50) values for products 1 and 2 with respect to hydratase activity are 0.15 and 0.32 µM for hCA I and 0.06 and 0.15 µM for hCA II, respectively. The IC50 values of the same inhibitors for esterase activity are 0.13 and 0.8 µM for hCA I and 0.14 and 0.1 µM for hCA II, respectively. In relation to esterase activities, the inhibition equilibrium constants (Ki) were also determined and found to be 0.137 and 0.99 µM on hCA I and 0.157 and 0.075 µM on hCA II for 1 and 2, respectively. The comparison of the inhibition studies of the newly synthesised compounds 1 and 2 to the parent compounds Hsba and amp and also to AAZ indicated that 1 and 2 have an effective inhibitory activity on hCA I and II, and might be used as potential inhibitors.  相似文献   

8.
Sulfonamide-bearing thiazole compounds were synthesized and their inhibitory effects on the activity of purified human carbonic anhydrase I and II were evaluated. Human carbonic anhydrase isoenzymes (hCA-I and hCA-II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of the 12 synthesized sulfonamide (5al) on the hydratase and esterase activities of these isoenzymes (hCA-I and hCA-II) were studied in vitro. In relation to these activities, the inhibition equilibrium constants (Ki) were determined. The results showed that all the synthesized compounds inhibited the CA isoenzyme activity. Among them 5b was found to be the most active (IC50?=?0.35?μM; Ki: 0.33?μM) for hCA I and hCA II.  相似文献   

9.
Indian Potato ( Ipomoea pandurata , Convolvulaceae)—A Record of Confusion. Once European explorers began sending back plants from distant lands, confusion developed regarding their identities. Among these was Ipomoea pandurata, which native peoples in the eastern United States considered to be a purgative. Unfortunately, edible plants like potatoes were confused with I. pandurata, and by the early 1900s Americans and Europeans began writing that indigenous peoples also ate its roots. The literature for the late 1900s into the 2000s mostly reports that I. pandurata is edible. Although no documented use for food by pre-European cultures in the Americas has been found, the myth persists that the roots were eaten on a regular basis.  相似文献   

10.
【目的】分离鉴定噬菌体,对其生物学特性进行研究,并筛选候选毒株为防控牛源无乳链球菌的感染提供依据。【方法】分别采用从牛奶或环境中分离、溶原菌诱导两种方法分离鉴定无乳链球菌噬菌体,利用双层琼脂平板法纯化。将新分离鉴定毒株与前期已分离鉴定的源自乳腺炎牛奶的无乳链球菌噬菌体JX01进行分析和比较,包括噬菌体透射电镜形态观察、对55株无乳链球菌和其他细菌的宿主谱鉴定、噬菌体基因Eco R I、Sal I、Xba I或Pst I的酶切图谱、最适MOI、吸附曲线和一步生长曲线、不同保存条件下的稳定性等。【结果】分离鉴定的3株噬菌体LYGO9、HZ04和p A11(诱导自牛源菌株HAJL2011070601)与JX01比对分析,结果显示,4株噬菌体均为长尾噬菌体;Eco R I、Sal I、Xba I、Pst I的酶切图谱分获4、3、3或2种带型,显示4株噬菌体为不同毒株;均特异性裂解牛源无乳链球菌,对42株牛源无乳链球菌的裂解率如下:LYGO9为28.6%(12/42)、p A11为31%(13/42)、HZ04为47.6%(20/42)、JX01为54.8%(23/42);同时,LYGO9与p A11、HZ04和JX01分别有共同宿主11、12和11株;HZ04与JX01有共同宿主18株,提示它们具有同源性。LYGO9感染宿主的潜伏期短,仅5 min,平均裂解量为30。分离株在SM液中4°C至少可保存1个月。【结论】分离鉴定的3株牛源无乳链球菌噬菌体均为长尾噬菌体,其中LYGO9潜伏期短、裂解量较大。  相似文献   

11.
In this study, 4-[5-(4-hydroxyphenyl)-3-aryl-4,5-dihydro-1H-pyrazol-1-yl]benzenesulfonamide derivatives (8-14) were synthesized for the first time by microwave irradiation and their chemical structures were confirmed by 1H NMR, 13C NMR and HRMS. Cytotoxic activities and inhibitory effects on carbonic anhydrase I and II isoenzymes of the compounds were investigated. The compounds 9 (PSE?=?4.2), 12 (PSE?=?4.1) and 13 (PSE?=?3.9) with the highest potency selectivity expression (PSE) values in cytotoxicity experiments and the compounds 13 (Ki?=?3.73?±?0.91?nM toward hCA I) and 14 (Ki?=?3.85?±?0.57?nM toward hCA II) with the lowest Ki values in CA inhibition studies can be considered as leader compounds for further studies.  相似文献   

12.
Abstract

In this study, newly synthesised compounds 6, 8, 10 and other compounds (1–5, 7 and 9) and their inhibitory properties against the human isoforms hCA I and hCA II were reported for the first time. Compounds 1–10 showed effective inhibition profiles with K I values in the range of 5.13–16.9?nM for hCA I and of 11.77–67.39?nM against hCA II, respectively. Molecular docking studies were also performed with Glide XP to get insight into the inhibitory activity and to evaluate the binding modes of the synthesised compounds to hCA I and II. More rigorous binding energy calculations using MM-GBSA protocol which agreed well with observed activities were then performed to improve the docking scores. Results of in silico calculations showed that all compounds obey drug likeness properties. The new compounds reported here might be promising lead compounds for the development of new potent inhibitors as alternatives to classical hCA inhibitors.  相似文献   

13.
Isaria fumosorosea is one of important entomopathogenic fungi showed a good potential in controlling Bemisia tabaci. The effects of I. fumosorosea Ifchit1 mutant (Ifchit1 gene deletion mutant) on the mortality, oviposition, and host immunological response of B. tabaci, on Brassica campestris L. plant, were evaluated under laboratory conditions. The wild-type fungal strain infection significantly increased insect mortality and reduced the oviposition effeciency of B. tabaci, whereas the Ifchit1 mutant was much less effective, resulting in higher survival and ovipositing of B. tabaci. The activities of four insect enzymes were examined during a time course of fungal infection. Insect phenoloxidase, perioxidase, and catalase activities were decreased in whiteflies treated with the wild type and mutant I. fumosorosea strain at 12–36?h post treatment. However, these enzyme activities increased in fungal-treated whiteflies as compared to controls between 36 and 60?h post-infection, reaching peak values. Superoxide dismutase activity in fungal-treated whiteflies was higher than that in controls during the entire experimental time course examined. The overall enzyme activity profiles in Ifchit1 mutant-treated whiteflies were significantly different from wild-type strain treatments. Our results showed that loss of the Ifchit1 gene in I. fumosorosea affects whitefly mortality, ovipositioning and various antioxidant enzyme activities, providing new insights into the role of chitinases in I. fumosorosea-insect host–pathogen interactions.  相似文献   

14.
In our search for new natural photosynthetic inhibitors that could lead to the development of “green herbicides” less toxic to environment, the diterpene labdane-8α,15-diol (1) and its acetyl derivative (2) were isolated for the first time from Croton ciliatoglanduliferus Ort. They inhibited photophosphorylation, electron transport (basal, phosphorylating and uncoupled) and the partial reactions of both photosystems in spinach thylakoids. Compound 1 inhibits the photosystem II (PS II) partial reaction from water to Na+ Silicomolibdate (SiMo) and has no effect on partial reaction from diphenylcarbazide (DPC) to 2,6-dichlorophenol indophenol (DCPIP), therefore 1 inhibits at the water splitting enzyme and also inhibits PS I partial reaction from reduced phenylmetasulfate (PMS) to methylviologen (MV). Thus, it also inhibits in the span of P700 to Iron sulfur center X (FX). Compound 2 inhibits both, the PS II partial reactions from water to SiMo and from DPC to DCPIP; besides this, it inhibits the photosystem I (PS I) partial reaction from reduced PMS to MV. With these results, we concluded that the targets of the natural product 2 are located at the water splitting enzyme, and at P680 in PS II and at the span of P700 to FX in PS I. The results of compounds 1 and 2 on PS II were corroborated by chlorophyll a fluorescence.  相似文献   

15.
Abstract

A series of polymethoxylated-pyrazoline benzene sulfonamides were synthesized, investigated for their cytotoxic activities on tumor and non-tumor cell lines and inhibitory effects on carbonic anhydrase isoenzymes (hCA I and hCA II). Although tumor selectivity (TS) of the compounds were less than the reference compounds 5-Fluorouracil and Melphalan, trimethoxy derivatives 4, 5, and 6 were more selective than dimethoxy derivatives 2 and 3 as judged by the cytotoxicity assay with the cells both types originated from the gingival tissue. The compound 6 (4-[3-(4-methoxyphenyl)-5-(3,4,5-trimethoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl] benzene sulfonamide) showed the highest TS values and can be considered as a lead molecule of the series for further investigations. All compounds synthesized showed superior CA inhibitory activity than the reference compound acetazolamide on hCA I, and II isoenzymes, with inhibition constants in the range of 26.5–55.5?nM against hCA I and of 18.9–28.8?nM against hCA II, respectively.  相似文献   

16.
A newly series of water-soluble 1-alkyl-3-(4-methyl-7, 8-dihydroxy-2H-chromen-2-one) benzimidazolium chloride salts (3a-j) were synthesized and their inhibitory effects on the activity of purified human carbonic anhydrase (hCA) I and II were evaluated. hCA I and II from human erythrocytes were purified by a simple one step procedure by using Sepharose 4B-L-tyrosine-sulphanilamide affinity column. The result showed that all the synthesized compounds were inhibited the CA isoenzymes activity. Among them, 3g and 3j were found to be most active (IC50 = 22.09 µM and 20.33 µM) for hCA I and hCA II, respectively.  相似文献   

17.
Phenolic mono Mannich bases [2-[4-hydroxy-3-(aminomethyl)benzylidene]-2,3-dihydro-1H-inden-1-one (815)] and bis Mannich bases [2-[4-hydroxy-3,5-bis(aminomethyl)benzylidene]-2, 3-dihydro-1H-inden-1-one (27)] were synthesized starting from 2-(4-hydroxybenzylidene)-2, 3-dihydro-inden-1-one (1). This study was designed in order to investigate the carbonic anhydrase (CA, EC 4.2.1.1) inhibitory properties of a library of compounds incorporating the phenol functional group. All prepared compounds showed a low inhibition percentages on both human (h) isoforms hCA I and hCA II compared to the reference sulfonamide acetazolamide. Mannich bases 215 had lower inhibition percentages than the compound 1 on hCA I and hCA II, except compound 14, which is a Mannich base derivative of dipropylamine, which had a similar inhibitory power as compound 1 on hCA II. All compounds synthesized 115 were 1.3–1.9 times more effective on hCA II comparing with the effectivenes of the compounds on hCA I.  相似文献   

18.
Abstract

Selective radiolabelling and imaging of transduced HSV tk expressing cells was studied using [123I]IVFRU, [125I]FIRU and [125I]FIAU. Although all three radionucleosides accumulated in the KBALB-STK transduced murine tumour line in vitro and in vivo, [125I]FIRU provided optimal performance in terms of selectivity for HSV tk expressing cells and % of injected dose accumulating in the tumor.  相似文献   

19.
Mannich bases of thymol were synthesized. The aminomethylation reaction was realised in the ortho position of the phenol for compounds 2 (dipropylamine), 3 (benzylamine), and 4 (dibenzylamine) while it was from para position for 1 (dimethylamine), 5 (piperidine), 6 (morpholine) and 7 (N-methylpiperazine). The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the compounds were asssessed against hCA I and hCA II. All compounds moderately inhibited hCA I and hCA II. The cytotoxicity of the compounds against four human oral squamous cell carcinoma cell lines were compared those against three normal oral cells. Tumor specificity values were about 2 or slightly more for the compounds 2, 3, 4, 5 and 6. Compound 2 showed cytostatic activity against OSCC cell lines at 16 to 32-fold lower concentrations as compared with normal cells. This suggests that compound 2 can be considered as cytotoxicity enhancing drug candidate for further investigations.  相似文献   

20.
Abstract

Pursuing on our efforts toward searching for efficient hCA IX and hCA XII inhibitors, herein we report the design and synthesis of new sets of benzofuran-based sulphonamides (4a,b, 5a,b, 9a–c, and 10a–d), featuring the zinc anchoring benzenesulfonamide moiety linked to a benzofuran tail via a hydrazine or hydrazide linker. All the target benzofurans were examined for their inhibitory activities toward isoforms hCA I, II, IX, and XII. The target tumour-associated hCA IX and XII isoforms were efficiently inhibited with K Is spanning in ranges 10.0–97.5 and 10.1–71.8?nM, respectively. Interestingly, arylsulfonehydrazones 9 displayed the best selectivity toward hCA IX and XII over hCA I (SIs: 39.4–250.3 and 26.0–149.9, respectively), and over hCA II (SIs: 19.6–57.1 and 13.0–34.2, respectively). Furthermore, the target benzofurans were assessed for their anti-proliferative activity, according to US-NCI protocol, toward a panel of sixty cancer cell lines. Only benzofurans 5b and 10b possessed selective and moderate growth inhibitory activity toward certain cancer cell lines.  相似文献   

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