scholarly journals Analysis of a gene family for PDF-like peptides from Arabidopsis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Reza Omidvar ◽  
Nadine Vosseler ◽  
Amjad Abbas ◽  
Birgit Gutmann ◽  
Clemens Grünwald-Gruber ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Three Dimensional ◽  
Disulfide Bridges ◽  
In Planta ◽  
E Coli ◽  
Highly Active ◽  
Plant Defensins ◽  
Low Levels ◽  
Basic Peptides

Abstract Plant defensins are small, basic peptides that have a characteristic three-dimensional folding pattern which is stabilized by four disulfide bridges. We show here that Arabidopsis contains in addition to the proper plant defensins a group of 9 plant defensin-like (PdfL) genes. They are all expressed at low levels while GUS fusions of the promoters showed expression in most tissues with only minor differences. We produced two of the encoded peptides in E. coli and tested the antimicrobial activity in vitro. Both were highly active against fungi but had lower activity against bacteria. At higher concentrations hyperbranching and swollen tips, which are indicative of antimicrobial activity, were induced in Fusarium graminearum by both peptides. Overexpression lines for most PdfL genes were produced using the 35S CaMV promoter to study their possible in planta function. With the exception of PdfL4.1 these lines had enhanced resistance against F. oxysporum. All PDFL peptides were also transiently expressed in Nicotiana benthamiana leaves with agroinfiltration using the pPZP3425 vector. In case of PDFL1.4 this resulted in complete death of the infiltrated tissues after 7 days. All other PDFLs resulted only in various degrees of small necrotic lesions. In conclusion, our results show that at least some of the PdfL genes could function in plant resistance.

scholarly journals Enzyme-catalyzed biodegradation of penicillin fermentation residues by β-lactamase OtLac from Ochrobactrum tritici

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Peng Wang ◽  
Chen Shen ◽  
Qinqin Cong ◽  
Kaili Xu ◽  
Jialin Lu
Keyword(s):  
Large Scale ◽  
In Vitro Study ◽  
Scale Removal ◽  
E Coli ◽  
Penicillin V ◽  
Highly Active ◽  
Steady State Kinetics ◽  
Biodegradation Process ◽  
Km Value

Abstract Background Biodegradation of antibiotics is a promising method for the large-scale removal of antibiotic residues in the environment. However, the enzyme that is involved in the biodegradation process is the key information to be revealed. Results In this study, the beta-lactamase from Ochrobactrumtritici that mediates the biodegradation of penicillin V was identified and characterized. When searching the proteins of Ochrobactrumtritici, the β-lactamase (OtLac) was identified. OtLac consists of 347 amino acids, and predicted isoelectric point is 7.0. It is a class C β-lactamase according to BLAST analysis. The coding gene of OtLac was amplified from the genomic DNA of Ochrobactrumtritici. The OtLac was overexpressed in E. coli BL21 (DE3) and purified with Ni2+ column affinity chromatography. The biodegradation ability of penicillin V by OtLac was identified in an in vitro study and analyzed by HPLC. The optimal temperature for OtLac is 32 ℃ and the optimal pH is 7.0. Steady-state kinetics showed that OtLac was highly active against penicillin V with a Km value of 17.86 μM and a kcat value of 25.28 s−1 respectively. Conclusions OtLac demonstrated biodegradation activity towards penicillin V potassium, indicating that OtLac is expected to degrade penicillin V in the future.

scholarly journals Newly developed dual topoisomerase inhibitor P8-D6 is highly active in ovarian cancer

2021 ◽  
Vol 13 ◽  
pp. 175883592110598
Author(s):  
Inken Flörkemeier ◽  
Tamara N. Steinhauer ◽  
Nina Hedemann ◽  
Magnus Ölander ◽  
Per Artursson ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Topoisomerase I ◽  
Ex Vivo ◽  
Chemotherapy Resistance ◽  
Membrane Integrity ◽  
Three Dimensional ◽  
New Drugs ◽  
Highly Active ◽  
Gynaecologic Neoplasms

Background: Ovarian cancer (OvCa) constitutes a rare and highly aggressive malignancy and is one of the most lethal of all gynaecologic neoplasms. Due to chemotherapy resistance and treatment limitations because of side effects, OvCa is still not sufficiently treatable. Hence, new drugs for OvCa therapy such as P8-D6 with promising antitumour properties have a high clinical need. The benzo[ c]phenanthridine P8-D6 is an effective inductor of apoptosis by acting as a dual topoisomerase I/II inhibitor. Methods: In the present study, the effectiveness of P8-D6 on OvCa was investigated in vitro. In various OvCa cell lines and ex vivo primary cells, the apoptosis induction compared with standard therapeutic agents was determined in two-dimensional monolayers. Expanded by three-dimensional and co-culture, the P8-D6 treated cells were examined for changes in cytotoxicity, apoptosis rate and membrane integrity via scanning electron microscopy (SEM). Likewise, the effects of P8-D6 on non-cancer human ovarian surface epithelial cells and primary human hepatocytes were determined. Results: This study shows a significant P8-D6-induced increase in apoptosis and cytotoxicity in OvCa cells which surpasses the efficacy of well-established drugs like cisplatin or the topoisomerase inhibitors etoposide and topotecan. Non-cancer cells were affected only slightly by P8-D6. Moreover, no hepatotoxic effect in in vitro studies was detected. Conclusion: P8-D6 is a strong and rapid inductor of apoptosis and might be a novel treatment option for OvCa therapy.

scholarly journals Evaluation du potentiel antimicrobien et de la toxicité des extraits de Jatropha multifida Linn, (Euphorbiaceae)

2020 ◽  
Vol 151 ◽  
pp. 15550-15558
Author(s):  
Amégninou Agban ◽  
Yao Hoekou ◽  
Passimna Pissang ◽  
Tchadjobo Tchacondo ◽  
Komlan Batawila
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Candida Albicans ◽  
Aqueous Extract ◽  
E Coli ◽  
Toxicological Studies ◽  
Jatropha Multifida

Objectif : L’objectif de ce travail était d’évaluer in vitro l’activité antimicrobienne des extraits de feuilles et tige de Jatropha multifida sur la croissance de Candida albicans, Escherichia coli et Staphylococcus aureus, puis d’évaluer in vivo la toxicité de cette plante. Méthodologie et résultats : Les méthodes de diffusion en milieu gélosé et de microdilution en milieu liquide ont été utilisées pour évaluer l’effet antimicrobien. Une étude en subaigüe était réalisée afin d’explorer les effets toxiques de l’extrait aqueux des feuilles. Les résultats des tests antimicrobiens montrent une activité des extraits de feuilles et tige de J. multifida sur la croissance des souches utilisées avec des diamètres de zones d’inhibition allant de 8 à 25 mm et des concentrations minimales inhibitrices (CMI) variant de 0,039 mg/mL à 1,25 mg/mL à l’exception des souches de E. coli qui sont résistantes aux extraits de la tige. L’administration en subaigüe de l’extrait aqueux des feuilles de J. multifida à la dose de 600 mg/kg entraîne une perte significative de poids chez les souris. Conclusion et applications des résultats : Les extraits aqueux, éthanolique et hydroéthanolique des feuilles et tige de J. multifida possèdent d’activité antimicrobienne et pourraient être utilisés dans le traitement des Candidoses à C. albicans et des infections à S. aureus. Mais l’essai de toxicité subaigüe montre que l’extrait aqueux de la plante serait toxique. Des études toxicologiques approfondies restent donc nécessaires sur ces extraits afin de mieux élucider leur inocuité. Mots-clés : Jatropha multifida, extraits de feuilles et de tige, activités antifongique et antibactérienne, toxicité. Agban et al., J. Appl. Biosci. 2020 Evaluation du potentiel antimicrobien et de la toxicité des extraits de Jatropha multifida Linn, (Euphorbiaceae) 15551 Evaluation of antimicrobial potential and toxicity of Jatropha multifida Linn, (Euphorbiaceae) extracts ABSTRACT Objective: The objective of this study was to evaluate in vitro the antimicrobial activity of leaves and stem of Jatropha multifida extracts against Candida albicans, Escherichia coli and Staphylococcus aureus, and then to evaluate in vivo the toxicity of this plant. Methodology and Results: The agar well-diffusion and the NCCLS broth microdilution methods were used to assess the antimicrobial effect. A subacute study was carried out to explore the toxic effects of the aqueous extract of the leaves. The results of the antimicrobial tests show an activity of the extracts of leaves and stems of J. multifida on the growth of the strains used with diameters of inhibitory zones ranging from 8 to 25 mm and minimum inhibitory concentrations (MIC) varying from 0.039 mg/mL to 1.25 mg/mL exception E. coli strains which are resistant to extracts from the stem. Subacute administration of the aqueous extract of the leaves of J. multifida at a dose of 600 mg/kg leads to a significant loss of weight in the mice. Conclusion and application of findings : The aqueous, ethanolic and hydroethanolic extracts of the leaves and stem of J. multifida have antimicrobial activity and could be used in the treatment of Candidiasis and bacterial infections due respectively to C. albicans and S. aureus. But the subacute toxicity test shows that the aqueous extract of the plant would be toxic. Extensive toxicological studies therefore remain necessary on these extracts in order to better elucidate their safety. Keywords: Jatropha multifida extracts of leaves and stem, antifungal and antibacterial activities, toxicity

scholarly journals Small molecule anion transporters display in vitro antimicrobial activity against clinically relevant bacterial strains

2019 ◽  
Vol 55 (68) ◽  
pp. 10080-10083 ◽  
Author(s):  
Israel Carreira-Barral ◽  
Carlos Rumbo ◽  
Marcin Mielczarek ◽  
Daniel Alonso-Carrillo ◽  
Enara Herran ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Small Molecule ◽  
Bacterial Strains ◽  
Antibiotic Resistant ◽  
In Vitro Antimicrobial Activity ◽  
Anion Transporters ◽  
Highly Active

Highly active transmembrane anion transporters have demonstrated their activity against antibiotic-resistant and clinically relevant bacterial strains.

scholarly journals Synthesis, Antimicrobial Activity and Molecular Docking of Novel Thiourea Derivatives Tagged with Thiadiazole, Imidazole and Triazine Moieties as Potential DNA Gyrase and Topoisomerase IV Inhibitors

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2766 ◽  
Author(s):  
Heba E. Hashem ◽  
Abd El-Galil E. Amr ◽  
Eman S. Nossier ◽  
Elsayed A. Elsayed ◽  
Eman M. Azmy
Keyword(s):  
Antimicrobial Activity ◽  
Molecular Docking ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Topoisomerase Iv ◽  
Thiourea Derivatives ◽  
E Coli ◽  
Cytotoxicity Studies ◽  
Ic50 Values

To develop new antimicrobial agents, a series of novel thiourea derivatives incorporated with different moieties 2–13 was designed and synthesized and their biological activities were evaluated. Compounds 7a, 7b and 8 exhibited excellent antimicrobial activity against all Gram-positive and Gram-negative bacteria, and the fungal Aspergillus flavus with minimum inhibitory concentration (MIC) values ranged from 0.95 ± 0.22 to 3.25 ± 1.00 μg/mL. Furthermore, cytotoxicity studies against MCF-7 cells revealed that compounds 7a and 7b were the most potent with IC50 values of 10.17 ± 0.65 and 11.59 ± 0.59 μM, respectively. On the other hand, the tested compounds were less toxic against normal kidney epithelial cell lines (Vero cells). The in vitro enzyme inhibition assay of 8 displayed excellent inhibitory activity against Escherichia coli DNA B gyrase and moderate one against E. coli Topoisomerase IV (IC50 = 0.33 ± 1.25 and 19.72 ± 1.00 µM, respectively) in comparison with novobiocin (IC50 values 0.28 ± 1.45 and 10.65 ± 1.02 µM, respectively). Finally, the molecular docking was done to position compound 8 into the E. coli DNA B and Topoisomerase IV active pockets to explore the probable binding conformation. In summary, compound 8 may serve as a potential dual E. coli DNA B and Topoisomerase IV inhibitor.

Screening of Antimicrobial Activity and Cytotoxic Effects of Two Cladonia Species

2013 ◽  
Vol 68 (5-6) ◽  
pp. 191-197 ◽  
Author(s):  
Birkan Açıkgöz ◽  
İskender Karaltı ◽  
Melike Ersöz ◽  
Zeynep M. Coşkun ◽  
Gülşah Çobanoğlu ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antimicrobial Activities ◽  
Chloroform Extract ◽  
Cytotoxic Effects ◽  
Minimal Inhibitory Concentrations ◽  
E Coli ◽  
Methanol Extracts ◽  
Gram Positive Bacteria

The present study explores the antimicrobial activity and cytotoxic effects in culture assays of two fruticose soil lichens, Cladonia rangiformis Hoffm. and Cladonia convoluta (Lamkey) Cout., to contribute to possible pharmacological uses of lichens. In vitro antimicrobial activities of methanol and chloroform extracts against two Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli), two Gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus), and the yeast Candida albicans were examined using the paper disc method and through determination of minimal inhibitory concentrations (MICs). The data showed the presence of antibiotic substances in the chloroform and the methanol extracts of the lichen species. The chloroform extracts exhibited more signifi cant antimicrobial activity than the methanol extracts. However, a higher antifungal activity was noted in the methanol extract of C. rangiformis. The maximum antimicrobial activity was recorded for the chloroform extract of C. convoluta against E. coli. The cytotoxic effects of the lichen extracts on human breast cancer MCF-7 cells were evaluated by the trypan blue assay yielding IC50 values of ca. 173 and 167 μg/ml for the extracts from C. rangiformis and C. convoluta, respectively.

scholarly journals Phytochemical characterization, anti-cancer and antimicrobial activity of isolated fractions of Alysicarpus vaginalis

2017 ◽  
Vol 12 (1) ◽  
pp. 77 ◽  
Author(s):  
Ganesh Tapadiya ◽  
Mayura A. Kale ◽  
Shweta Saboo
Keyword(s):  
Antimicrobial Activity ◽  
Cell Lines ◽  
Methanolic Extract ◽  
Hep G2 ◽  
Zone Of Inhibition ◽  
E Coli ◽  
Anti Cancer ◽  
Proliferative Assay ◽  
Bacteria And Fungi

<p class="Abstract">The methanolic extract of <em>Alysicarpus </em>vaginalis was selected for fractionation due to its known reported biological activity. The four fractions were separated and subjected for<em> in vitro</em> antimitotic and anti-proliferative assays along with anti-cancer activity on two human cancers cell lines (SK-MEL-2 and Hep-G2). The antimicrobial potential of fractions had been evaluated against bacteria and fungi. From all fractions, acetone and n-butanol fractions were effective against the cell lines. They show strong inhibitory action with mitotic index 6.2 and 8.4 mg/mL and IC<sub>50 </sub>values of anti-proliferative assay in between 19.7 to 14.2 mg/mL respectively, which was found to be comparable to the standard methothrexate 5.9 mg/mL and 13.2 mg/mL respectively. In antimicrobial activity, the zone of inhibition had been observed in the range of 12-27 mm and MIC value was found in the range of 0.2-0.1 mg/mL. The acetone fraction was found to be most active against fungi, and<em> E. coli</em> whereas chloroform and n-butanol fractions were more effective against <em>S. aureus</em> and <em>B. </em>subtilis. The phytochemical characterization by HPLC analysis indicated the presence of important polyphenolic and steroidal compounds.</p>

scholarly journals 2214. Comparison of Cefepime–Zidebactam (WCK 5222), Ceftazidime–Avibactam, and Ceftolozane–Tazobactam Tested Against Gram-Negative Organisms Causing Pneumonia in United States Hospitals in 2018

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S755-S755 ◽  
Author(s):  
Helio S Sader ◽  
Cecilia G Carvalhaes ◽  
Rodrigo E Mendes ◽  
Mariana Castanheira ◽  
Robert K Flamm
Keyword(s):  
Therapeutic Option ◽  
High Dose ◽  
Gram Negative ◽  
E Coli ◽  
Highly Active ◽  
Medical Centers ◽  
Carbapenem Resistant ◽  
Gram Negative Organisms ◽  
Dual Mechanism

Abstract Background Zidebactam (ZID) is a bicyclo-acyl hydrazide antibiotic with a dual mechanism of action: selective Gram-negative PBP2 binding and β-lactamase inhibition. We evaluated the frequency and antimicrobial susceptibility (S) of Gram-negative bacilli (GNB) isolated from patients with pneumonia in US hospitals. Methods All 3,086 clinical isolates were consecutively collected from patients hospitalized with pneumonia (1/patient) in 29 US medical centers in 2018, and the GNB (n = 2,171) were S tested against cefepime (FEP)-ZID (1:1 ratio) and comparators by reference broth microdilution methods. The FEP S breakpoint of ≤8 mg/L (CLSI, high dose) was applied to FEP-ZID for comparison purposes. An FEP-ZID S breakpoint of ≤64 mg/L has been proposed for non-fermentative GNB based on pharmacokinetic/pharmacodynamic target attainment and was applied. Enterobacterales (ENT) isolateswere screened for β-lactamase genes by whole-genome sequencing. Results GNB represented 70.3% of the collection, and the most common GNB were P. aeruginosa (PSA; 34.9% of GNB), K. pneumoniae (10.9%), E. coli (9.7%), S. marcescens (7.7%), and S. maltophilia (XM; 6.4%). FEP-ZID was highly active against PSA (MIC50/90, 2/8 mg/L; 98.8% and 99.9% inhibited at ≤8 and ≤16 mg/L, respectively; highest MIC, 32 mg/L), including resistant subsets (table). Among comparators, colistin (99.6%S), ceftazidime–avibactam (CAZ-AVI; 95.2%S), and ceftolozane–tazobactam (C-T; 94.5%S) were the most active compounds against PSA. FEP-ZID inhibited all ENT at ≤4 mg/L, including ESBL-producers (MIC90, 0.25 mg/L) and carbapenem-resistant ENT (MIC90, 4 mg/L). The most active comparators against ENT were CAZ-AVI (99.9%S), amikacin (98.5%S), and meropenem (MEM; 98.3%S). FEP-ZID inhibited 75.0% and 97.9% of XM isolates at ≤8 and ≤16 mg/L, respectively (highest MIC, 64 mg/L). The only other compounds active against XM were co-trimoxazole (MIC50/90, ≤0.12/2 mg/L; 95.7%S) and levofloxacin (MIC50/90, 1/2 mg/L; 70.7%S). FEP-ZID inhibited 71.0% and 98.9% of A. baumannii isolates at ≤8 and ≤64 mg/L,, respectively. Conclusion FEP-ZID showed potent in vitro activity against GNB causing pneumonia in US hospitals and may represent a valuable therapeutic option for these difficult-to-treat infections Disclosures All authors: No reported disclosures.

Antimicrobial activity of recombinant E. coli expressed chicken AvBD-2 and its mRNA expression in Indian native Aseel and Kadaknath chicken breeds

2017 ◽  
Author(s):  
T. R. Kannaki ◽  
M. R. Reddy ◽  
P. C. Verma
Keyword(s):  
Antimicrobial Activity ◽  
Mrna Expression ◽  
Affinity Column ◽  
White Leghorn ◽  
Coding Region ◽  
Recombinant Peptide ◽  
E Coli ◽  
Significant Difference ◽  
Chicken Breeds

Avian b defensins (AvBD) are antimicrobial peptides that play a crucial role in the innate immune response in chickens. In the present study, chicken AvBD2 gene was cloned, expressed in E. coli system and the in vitro antimicrobial activity of recombinant peptide was evaluated. The entire mature peptide region of chicken AvBD2 region was amplified and cloned in pUC29 cloning vector. Further, the coding region was sub cloned in pET-28A expression vector. After transformation in E. coli cells, the peptide synthesis was induced and recombinant protein (7.7 kDa) was purified by using Ni-NTA affinity column. The recombinant chicken AvBD2 showed antibacterial activity against S. Pullorum. The minimum bactericidal concentration (MBC) of recombinant chicken AvBD2 evaluated by micro-broth dilution assay was 35 µg/ ml. We also quantified the expression of AvBD2 transcript expression in day-old spleen tissue of Indian native chicken breeds (Aseel and Kadaknath) and White Leghorn. Measurable AvBD2 mRNA expression was found in the spleen of all three breeds. However, no significant difference was found in AvBD2 gene expression between native chickens and White Leghorn.

Functional and structural differences between photosynthetic and heterotrophic Rhodospirillum rubrum ribosomes and S-100 fractions

1976 ◽  
Vol 22 (10) ◽  
pp. 1522-1539 ◽  
Author(s):  
C. T. Chow
Keyword(s):  
Rhodospirillum Rubrum ◽  
Photosynthetic Pigment ◽  
Free Protein ◽  
E Coli ◽  
Highly Active ◽  
Structural Differences ◽  
S 100 ◽  
Cell Free Protein Synthesis ◽  
Fraction Addition

Cell-free, protein-synthesizing activity has been tested by using various combinations of the S-100 and ribosome fractions prepared from photosynthetic and heterotrophic Rhodospirillum rubrum. The photosynthetic ribosomes are highly active when combined with either the photosynthetic or the heterotrophic S-100 fractions, whereas the heterotrophic ribosomes are active only when combined with the photosynthetic S-100 fraction. Addition of a photosynthetic pigment-containing fraction to the homologous heterotrophic system is, however, able to stimulate its activity. An inhibitor and an activator involved in cell-free protein synthesis have been isolated from the stationary heterotrophic cells. The inhibitor is a very small, dialyzable compound which inhibits not only the R. rubrum but also the E. coli protein-synthesizing activity in vitro, whereas the activator is a non-dialyzable, small RNA molecule capable of stimulating only the R. rubrum activity. Differences exist between the photosynthetic and the heterotrophic systems in their response to various chemical compounds and to light as well as in their structure.

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