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1.
We induced 3 cell lines that were in vitro cultured from Lepidoptera with heat inactivated Escherichia coil DH5α to stimulate the antibacterial peptide followed by antibacterial activity assay,induction dynamic research and Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine SDS-PAGE) experiment.The antibacterial activity of the induced BTI-Tn-5B1 cell line was the highest,and the antibacterial activity increased gradually to the highest level in 16 hours after stimulation.A new antibacterial peptide with a molecular weight of about 8000 Da was preferentially induced in Trichoplusia ni BTI-Tn-5B1 ceils in 16 hours after stimulation.Antibacterial activity assays indicated that it had inhibition against Staphylococcus aureus,Escherichia coli K12D31 and Salmonella derby.It has especially strong inhibition against Gram-negative bacteria such as Escherichia coli KI2D31 and Salmonella derby. 相似文献
2.
Yu Cao Rong Qing Yu Yi Liu Huo Xiang Zhou Ling Ling Song Yi Cao Dai Rong Qiao 《Current microbiology》2010,61(3):169-175
In order to evaluate their antibacterial activities and toxicities, the cecropins–melittin hybrid antimicrobial peptide, CA(1-7)-M(4-11)
(CAM) and CB(1-7)-M(4-11) (CBM), were designed by APD2 database. The recombinant hybrid antimicrobial peptides were successfully
expressed and purified in Pichia pastoris. Antimicrobial activity assay showed that both of the two hybrid antimicrobial peptides had strong antibacterial abilities
against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Bacillus subtilis, Bacillus thuringiensis, and Salmonella derby. The potency of CAM and CBM to E. coli 25922 were 0.862 and 0.849, respectively, slightly lower than Amp’s 0.957. The hemolytic assays indicated CAM and CBM had
no hemolytic in vivo and in vitro, and so they had a good application prospect. 相似文献
3.
Massa S. Petruccioli M. Brocchi Giada F. Altieri Clelia Sinigaglia Milena Spano G. 《World journal of microbiology & biotechnology》2001,17(3):287-291
The antibacterial effect of different glucose oxidase (GOX)/glucose combinations was studied on two food-poisoning organisms, enterotoxic Escherichia coli PM 015 and Salmonella derby BP 177. Growth of E. coli in nutrient broth (NB) was clearly inhibited by 4.0 mg/ml glucose after 24 h when combined with 2.0 U/ml GOX and after 48 h when combined with 0.5 or 1.0 U/ml GOX. Salmonella derby was more resistant than E. coli, but showed clear growth inhibition only after 48 h when inoculated in tubes where 2 mg glucose/ml and 2 U GOX/ml (or 4 mg glucose/ml and 1 U GOX/ml) were combined. In order to understand if the enzyme effect on microbial growth can be attributed to hydrogen peroxide or to pH decrease as a result of the production of gluconic acid, catalase (CAT) was added to GOX/glucose system. Since CAT decomposes H2O2 to H2O and O2, the antibacterial effect was ascribed to a pH decrease as a result of gluconic acid in the system. 相似文献
4.
The antibacterial peptide CM4 (ABP-CM4), isolated from Chinese Bombys mori, is a 35-residue cationic, amphipathic α-helical peptide that exhibits a broad range of antimicrobial activity. To explore
a new approach for the expression of ABP-CM4 in E. coli, the gene ABP-CM4, obtained by recursive PCR (rPCR), was cloned into the vector pET32a to construct a fusion expression plasmid.
The fusion protein Trx-CM4 was expressed in soluble form, purified by Ni2+-chelating chromatography, and cleaved by formic acid to release recombinant CM4. Purification of rCM4 was achieved by affinity
chromatography and reverse-phase HPLC. The purified of recombinant peptide showed antimicrobial activities against E. coli K12D31, Penicillium chrysogenum, Aspergillus niger and Gibberella saubinetii. According to the antimicrobial peptide database (http://aps.unmc.edu/AP/main.html), 116 peptides contain a Met residue, but
only 5 peptides contain the AspPro site, indicating a broader application of formic acid than CNBr in cleaving fusion protein.
The successful application to the expression of the ABP-CM4 indicates that the system is a low-cost, efficient way of producting
milligram quantities of ABP-CM4 that is biologically active. 相似文献
5.
Ruidong Miao Xiaohui Xia Dongling Yang Minghua Lü Qin Wang 《Frontiers of Biology in China》2008,3(3):275-278
Abstract We evaluated the inhibitory effect of 3,7-dinitrodibenzobromonium salts (cBr) on the proliferation of human chronic
myelogenous leukemia K562 cell by trypan blue exclusion test and MTT colorimetric assay. The degree of DNA damage in K562 cells treated with cBr, was detected by isotopic tracer method (3H-TdR). The morphological changes of these K562 cells were examined by fluorescence and electron microscopy. Biochemical characteristics of K562 cells were detected by flow cytometry and 3H-thymidine incorporation assay. Findings indicated that cBr could significantly inhibit cell proliferation and result in
DNA damage of K562 cells. cBr is a new type of immunostimulant and can induce cell apoptosis.
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Translated from Journal of Lanzhou University (Natural Sciences), 2006, 42(6): 49–61 [译自: 兰州大学学报(自然科学版)] 相似文献
6.
Wang Shujing Liu Yan Lin Xuesong Fu Xue Xu Jianyong Liu Xinghan 《Frontiers of Biology in China》2007,2(3):276-283
To obtain an anti-tumor peptide of Tumstatin and detect its biological activity, the nucleotide sequence encoding 185–203
amino acids (19peptide) of Tumstatin was synthesized and inserted into the fusion protein vector pTYB2. After identification
by sequencing and restriction endonucleases, the recombined vector was transformed into BL-21 (DE3) E. coli competent cells. Transformed E. coli BL-21 (DE3) were induced by isopropyl-β-thiogalactopyranoside (IPTG), and then expressed. By 1,4-dithiothreitol (DTT) reduction,
the soluble 19peptide was obtained from a chitin affinity chromatograph. The biological activity of 19peptide was determined
by 3-[4,5-dimethylthiazol-2-y1]-2,5-diphenytetrazolium bromide (MTT) assay, cell growth curve, the effect of the ascitic fluid
transfevent H22 hepatoma on mice and via histopathological slices. The purified 19peptide directly inhibited proliferation
and migration of murine B16 melanoma cells, SMMC-7721hepatoma carcinoma cells and human umbilical vein endothelial cells (HUVEC).
The tumor inhibition rate of mice ascitic fluid transfevent H22 hepatoma was 48.46%. Histopathological slices showed that
it could promote tumor tissue necrosis and decrease the density of blood vessels. With higher anti-tumor activity, 19peptide
has the potential to become a novel, potent anti-tumor agent.
Translated from Chinese Journal of Biochemistry and Molecular Biology, 2005, 21(3): 322–328 [译自: 中国生物化学与分子生物学学报] 相似文献
7.
《Molecular membrane biology》2013,30(4):206-215
AbstractThe antimicrobial property of stabilized silver nanoparticles (AgNPs) with phospholipid membrane was investigated on both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacterial strains. The influence of phospholipid concentrations on antibacterial kinetics actions of AgNPs was studied with two different methodologies in order to understand the bactericidal and bacteriostatic effects. The bacterial inactivation of synthesized AgNPs fitted well to the Chick-Watson model with a high regression coefficient, R2 > 0.91. The antibacterial properties of AgNPs depend on the particle size, stabilizer and lecithin concentrations. Only the stabilized AgNPs that have the Klec/Ag values of 1 and 2 presented the inhabitation zone, while unstabilized AgNPs agglomerated quickly, settled on the wells and did not diffuse in agar. In addition, the specific coefficient of lethality depends on the lecithin concentration. An increase in lecithin concentration caused multilayer creation on the AgNPs' surface and reduced the release of AgNPs which led to low bacterial killing rate. 相似文献
8.
Ma Yonggang Yu Hong Wang Jinzhong Chen Qimin Geng Yunqi 《Frontiers of Biology in China》2006,1(4):353-356
Foamy viruses (FVs) have broad cellular tropism infecting vertebrates from fish to human being, which indicates that Env protein
has a high capability for membrane fusion. Conservative features in all FV transmembrane (TM) proteins include a region of
hydrophobic domain called membrane-spanning domain (MSD), which contains several stretches of hydrophobic amino acids. To
investigate whether these features were associated with the cytotoxicity effect of TM on Escherichia coli, a series of mutants were constructed and expressed in the E. coli BL21 (DE3) using pET-32a (+) as expressing vector. The results showed that only TM3 without MSD was expressed in E. coli, whereas the other two containing full or part of the MSD (TM1 and TM2) could not be expressed. Furthermore, the bacterial
amount and living bacteria analysis revealed that the cytotoxicity of TM was dependent on its MSD, especially on the stretches
of hydrophobic amino acids. Western blotting analysis showed that TM3 protein was purified with affinity purification.
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Translated from Acta Scientiarum Naturalium Universitatis Nankaiensis, 2005, 38(2): 49–53 [译自: 南开大学学报 (自然科学版), 2005, 38(2): 49–53] 相似文献
9.
AFLP analysis of genetic diversity and relationship among some Chinese domestic ducks and wild ducks
Yan Feihuan Zuo Zhenghong Chen Mei Song Yueqiang Lü Liangju Chen Yixin 《Frontiers of Biology in China》2006,1(3):280-284
The amplified fragment length polymorphic (AFLP) technique was used to analyze the genome DNA polymorphism among 8 breeds
of domestic ducks and 2 species of wild ducks. Nine of the 17 selected primers pairs gave reproducible polymorphic DNA amplification
bands. The amplified bands ranged from 44 to 83 per primer pair. Of the 513 AFLP markers obtained, 498 were polymorphic. The
proportion of polymorphic loci was 97.1%. The genetic distance (D) and similarity coefficients (GS) were calculated based on the polymorphic data. Between domestic ducks D ranged from 0.331 to 0.589, while between domestic ducks and the wild ducks, it ranged from 0.298 to 0.520 (vs. Anas Platyrhynchos) and from 0.316 to 0.522 (vs. A. Poecilorhyncha), respectively. The variance analysis showed no significant difference between the two groups of data, which indicated that
both mallard and spot-billed ducks made contributions to domestic duck evolution. A dendrogram was constructed according to
the D value.
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Translated from Journal of Xiamen University (Natural Science), 2005, 44(5): 729–733 [译自: 厦门大学学报 (自然科学版), 2005, 44(5): 729–733] 相似文献
10.
Tang Yunming Cen Liang Chu Bo Li Changchun Xu Min Luo Ying Lu Cheng 《Frontiers of Biology in China》2006,1(3):246-253
Alkaline phosphatase (AKP), from the succus entericus of silkworm, was purified using 10%–50% ammonium sulfate fractions,
ion exchange chromatography of DEAE-Sepharose, and size exclusion chromatography of Sephacryl S-200. The purification fold
was 464 times and specified activity was 3 936 U/mg. Optimum pH value of the phosphatase was 10.5, and was stable between
pH 7.5 and 11. The optimum temperature of the phosphatase was 40°C and it was unstable over 50°C. K
m value of the phosphatase was 1.25 mmol/L. In a given condition, the phosphatase was selectively modified by PCMB, NBS, PMSF,
TNBS, SUAN, DTT, BrAc, and IAc, the results indicate that PMSF, SUA, BrAc, IAc, and TNBS could obviously inhibit the activity
of the phosphatase, and the degree of inhibition depended on the concentration of these reagents. There was little effect
on the activity of phosphatase after treatment by PMSF, DTT, and NBT. We primarily conclude that mercapto and imidazole are
essential for AKP from silkworm. Also, Lys residue and disulfide bands are necessary to protect the catalysis of the AKP.
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Translated from Journal of Southwest Normal University (Natural Science), 2005, 30(5): 925–934 [译自: 西南师范大学学报 (自然科学版), 2005, 30(5): 925–934] 相似文献
11.
Zahid H. Chohan Ali U. Shaikh Muhammad M. Naseer Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):771-781
A new series of antibacterial and antifungal furanyl-derived sulfonamides and their cobalt (II), copper (II), nickel (II) and zinc (II) metal complexes have been synthesized, characterized and screened for their in-vitro antibacterial activity against four Gram-negative (Escherichia coli, Shigella flexneri, Pseudomonas aeruginosa and Salmonella typhi) and two Gram-positive (Bacillus subtilis and Staphylococcus aureus) bacterial strains and, for in-vitro antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. The results of these studies revealed that all compounds showed significant to moderate antibacterial activity. However, the zinc (II) complexes were found to be comparatively much more active as compared to the others. For antifungal activity generally, compounds (22) and (24) showed significant activity against Escherichia coli (a), (6) against Shigella flexeneri (b), (16) and (22) against Pseudomonas aeruginosa (c), (14) and (16) against Salmonella typhi (d), (9) against Staphylococcus aureus (e) and, (14) and (16) against Bacillus subtilis (f) fungal strains. The brine shrimp (Artemia salina) bioassay was also carried out to study their in-vitro cytotoxic properties. Only three compounds, (6), (10) and (23) displayed potent cytotoxic activity with LD50 = 1.8535 × 10? 4, 1.8173 × 10? 4 and 1.9291 × 10? 4 respectively. 相似文献
12.
M. M. Rigano A. Romanelli A. Fulgione N. Nocerino N. D'Agostino C. Avitabile L. Frusciante A. Barone F. Capuano R. Capparelli 《Journal of peptide science》2012,18(12):755-762
Defensins are a class of cysteine‐rich proteins, which exert broad spectrum antimicrobial activity. In this work, we used a bioinformatic approach to identify putative defensins in the tomato genome. Fifteen proteins had a mature peptide that includes the well‐conserved tetradisulfide array. We selected a representative member of the tomato defensin family; we chemically synthesized its γ‐motif and tested its antimicrobial activity. Here, we demonstrate that the synthetic peptide exhibits potent antibacterial activity against Gram‐positive bacteria, such as Staphylococcus aureus A170, Staphylococcus epidermidis, and Listeria monocytogenes, and Gram‐negative bacteria, including Salmonella enterica serovar Paratyphi, Escherichia coli, and Helicobacter pylori. In addition, the synthetic peptide shows minimal (<5%) hemolytic activity and absence of cytotoxic effects against THP‐1 cells. Finally, SolyC exerts an anti‐inflammatory activity in vitro, as it downregulates the level of the proinflammatory cytokines TNF‐α and IFN‐γ. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
13.
Yong-Liang Wang Bin-Yuan Hu Meng-An Qian Zi-Hang Wang Jing-Mei Zou Xu-Yan Sang Lei Li Xiao-Dong Luo Li-Xing Zhao 《化学与生物多样性》2021,18(9):e2100460
A new compound named koninginin W ( 1 ) and four known polyketides ( 2 – 5 ) were isolated from endophytic fungus Trichoderma koningiopsis YIM PH30002 of Panax notoginseng. The structures of 1 - 5 , including absolute configuration of 1 , were elucidated on the detailed analysis of the HR-ESI-MS, 1D and 2D NMR, and X-ray crystallographic data. Koninginin W ( 1 ) presented weak antibacterial activity against Escherichia coli, Bacillus subtilis and Salmonella typhimurium. 相似文献
14.
15.
Antibacterial activity of ZnO nanoparticles prepared via non-hydrolytic solution route 总被引:1,自引:0,他引:1
Rizwan Wahab Amrita Mishra Soon-Il Yun Young-Soon Kim Hyung-Shik Shin 《Applied microbiology and biotechnology》2010,87(5):1917-1925
The antibacterial activity of ZnO nanoparticles has been investigated and presented in this paper. Nanoparticles were prepared
via non-hydrolytic solution process using zinc acetate di-hydrate (Zn(CH3COO)2·2H2O) and aniline (C6H5NH2) in 6 h refluxing at ∼65 °C. In the presence of four pathogens such as Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Klebsiella pneumoniae, the antibacterial study of zinc oxide nanoparticles were observed. The antibacterial activity of ZnO nanoparticles (ZnO-NPs) were studied by spectroscopic method taking different concentrations
(5–45 μg/ml) of ZnO-NPs. Our investigation reveals that the lowest concentration of ZnO-NPs solution inhibiting the growth
of microbial strain is found to be 5 μg/ml for K. pneumoniae, whereas for E. coli, S. aureus, and S. typhimurium, it was calculated to be 15 μg/ml. The diameter of each ZnO-NPs lies between “20 and 30 nm” as observed from FESEM and transmission
electron microscopy images. The composition of synthesized material was analyzed by the Fourier transform infrared spectroscopy,
and it shows the band of ZnO at 441 cm−1. Additionally, on the basis of morphological and chemical observations, the chemical reaction mechanism of ZnO-NPs was also
proposed. 相似文献
16.
Ravi K. Asthana Arunima Srivastava Akhilesh P. Singh Deepali Sureshwar P. Singh Gopal Nath Ranjana Srivastava Brahm S. Srivastava 《Journal of applied phycology》2006,18(1):33-39
The active principle in a methanolic extract of the laboratory-grown cyanobacterium, Fischerella sp. isolated from Neem (Azadirachta indica) tree bark was active against Mycobacterium tuberculosis, Enterobacter aerogenes, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli as well as three multi-drug resistant E. coli strains in in vitro assays. Based on MS, UV, IR 1H NMR analyses the active principle is proposed to be hapalindole T having the empirical formula C21H23N2ClSO and a molecular weight of 386 with the melting point range 179–182 °C. The estimated production of Hapalindole T from the cyanobacterium is 1.25 mg g−1 lyophilized biomass. It is suggested that cyanobacteria colonizing specialized niches such as tree bark could be an antibacterial drug resource. 相似文献
17.
Ma Ting Li Shanshan Li Guoqiang Wang Renjing Liang Fenglai Liu Rulin 《Frontiers of Biology in China》2006,1(4):375-380
Dibenzothiophene (DBT) monooxygenase (DszC) catalysis, the first and also the key step in the microbial DBT desulfurization,
is the conversion of DBT to DBT sulfone (DBTO2). In this study, dszC of a DBT-desulfurizing bacterium Rhodococcus sp. DS-3 was cloned by PCR. The sequence cloned was 99% homologous to Rhodococcus erythropolis IGTS8 that was reported in the Genebank. The gene dszC could be overexpressed effectively after being inserted into plasmid pET28a and transformed into E. coli BL21 strain. The expression amount of DszC was about 20% of total supernatant at low temperature. The soluble DszC in the
supernatant was purified by Ni2+ chelating His-Tag resin column and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to electronics purity.
Only one band was detected by Western-blotting, which is for the antibody released in mouse against purified DszC in the expression
product of BL21 (DE3, paC5) and Rhodococcus sp. DS-3. The activity of purified DszC was 0.36 U. DszC can utilize the organic compound such as DBT and methyl-DBT, but
not DBT derivates such as DBF, which has no sulfur or inorganic sulfur.
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Translated from Acta Scientiarum Naturalium Universitatis Nankaiensis, 2005, 38(6): 1–6 [译自: 南开大学学报 (自然科学版), 2005, 38(6): 1–6] 相似文献
18.
Antimicrobial peptides will be attractive and potential candidates as peptide drugs because of their efficient action against
microbes and low toxicity to mammal cells. To improve their antibacterial activity, some modifications needs to be made. In
this research, the hybrid peptide gene Attacin-Thanatin with 642 bp in length with preferred codons of E. coli was generated using the technology of Gene splicing by overlap extension. The gene was inserted in-frame into E. coli expression plasmid pET-32a (+) and induced to express in E. coli
Rosetta. The recombinant protein was partial purified and its biological activity was determined. Analysis of the E. coli
Rosetta induced with IPTG revealed that the molecular weight of fusion protein was approximately 41.8 kDa, which perfectly matched
the mass calculated from the amino acid sequence. Biological activity detection showed that this peptide effectively inhibited
the growth of the test bacteria including E. coli DH5α, E. coli BL21 (DE3), Salmonella choleraesuis and Staphylococcus aureus. Among these bacteria, the Gram-negative E. coli was the most sensitive. Furthermore, there was minor hemolysis activity for porcine red blood cells. So, the results indicated
that the hybrid peptide Attacin-Thanatin could be served as a promising candidate for the chemical antibiotics. 相似文献
19.
Group 1B human pancreatic secretory phospholipase A2 (hp-sPLA2), a digestive enzyme synthesized by pancreatic acinar cells and present in pancreatic juice, do not have antibacterial activity towards Escherichia coli. Our earlier results suggest that the N-terminal first ten amino acid residues of hp-sPLA2 constitute major portion of the membrane binding domain of full-length enzyme and is responsible for the precise orientation of enzyme on the membrane surface by inserting into the lipid bilayers (Pande et al. (2006) Biochemistry, 45,12436–12447). In this study we report the antibacterial properties of a peptide (AVWQFRKMIK-CONH2; N10 peptide), which corresponds to the N-terminal first ten amino acid residues of hp-sPLA2, against E. coli. Full-length hp-sPLA2, which contains this peptide sequence as N-terminal α-helix, did not showed detectable antibacterial activity. Presence of physiological concentration of salt or preincubation of N10 peptide with soluble anionic polymer inhibits the antibacterial activity indicating the importance of electrostatic interaction in binding of peptide to bacterial membrane. Addition of peptide resulted in destabilization of outer as well as inner cytoplasmic membrane of E. coli suggesting bacterial membranes to be the main target of action. N10 peptide exhibits strong synergism with lysozyme and potentiates the antibacterial activity of lysozyme. The peptide was inactive against human erythrocyte. Our result shows for the first time that a peptide fragment of hp-sPLA2 possesses antibacterial activity towards E. coli and at subinhibitory concentration and can potentiate the antibacterial activity of membrane active enzyme. These observations suggest that N10 peptide may play an important role in the antimicrobial activity of pancreatic juice. 相似文献
20.
为探索贵州苗药光枝勾儿茶内生真菌类群特征、分布部位及其抑菌活性,该研究采用传统方法对贵州省贵阳市和黔西市光枝勾儿茶内生真菌进行分离,并基于分子生物学及统计学对其分类地位进行鉴定及多样性评价,最后通过微量肉汤倍比稀释法筛选具有抑菌活性的菌株。结果表明:(1)从光枝勾儿茶中分离到191 株内生真菌,隶属于3 个门5 个纲10 个目15 个科19 个属,优势属为叶点霉属(Phyllosticta)、间座壳属(Diaporthe)、葡萄座腔菌属(Botryosphaeria)和刺盘孢属(Colletotrichum)。(2)黔西光枝勾儿茶内生真菌香农-维纳多样性指数(H''Q=2.112)较贵阳(H''G=1.801)高,索伦森相似性指数CsG-Q为0.923,不同组织香农-维纳多样性指数为茎(H''S=2.004)>根(H''R=1.764)>叶(H''L=1.654)>果实(H''F=1.473),茎和叶内生真菌的索伦森相似性最高(CsS-L=0.667)。(3)筛选出的21株内生真菌对供试菌大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)和沙门氏菌(Salmonella enterica)具有抑菌效果,其中Diaporthe sp. QX4G6对大肠杆菌、金黄色葡萄球菌和沙门氏菌的最小抑菌浓度分别为12.5、6.25、12.5 mg·mL-1,最小杀菌浓度分别为12.5、6.25、12.5 mg·mL-1。以上研究结果揭示了光枝勾儿茶蕴藏丰富的内生真菌资源,不同地区及组织内生真菌类群组成有差异,多个分离菌株具有抗菌活性,为光枝勾儿茶内生真菌天然抗菌药物或药源研发奠定了基础。 相似文献