scholarly journals Lipid-binding and antimicrobial properties of synthetic peptides of bovine apolipoprotein A-II

1999 ◽  
Vol 342 (1) ◽  
pp. 215-221 ◽  
Author(s):  
Mitsuyoshi MOTIZUKI ◽  
Takehito ITOH ◽  
Takanori SATOH ◽  
Sadaki YOKOTA ◽  
Muneo YAMADA ◽  
...  

We previously showed that bovine apolipoprotein A-II (apoA-II) had antimicrobial activity against Escherichia coli and the yeast Saccharomyces cerevisiae in PBS. We have characterized here the active domain of apoA-II using synthetic peptides. A peptide corresponding to C-terminal residues Leu49-Thr76 exhibited significant antimicrobial activity against E. coli in PBS, but not against S. cerevisiae. Experiments using amino-acid-substituted peptides indicated that the residues Phe52-Phe53-Lys54-Lys55 are required for the activity. Peptide Leu49-Thr76 induced the release of calcein trapped inside the vesicles whose lipid composition resembles that of E. coli membrane, suggesting that peptide Leu49-Thr76 can destabilize the E. coli membrane. CD measurements showed that the α-helicity of peptide Leu49-Thr76 increased from 3.5 to 36% by addition of the vesicles. When E. coli cells were incubated with peptide Leu49-Thr76, some proteins were released to the external medium, probably owing to membrane destabilization caused by the peptide. In electron micrographs of E. coli cells treated with peptide Leu49-Thr76, transparent nucleoids and granulated cytoplasm were observed. Amino acid substitutions, Phe52Phe53 → AlaAla (Phe52,53 → Ala) in peptide Leu49-Thr76 caused the loss of antimicrobial activity against E. coli, although protein-releasing activity was retained. Electron micrographs of the cells treated with peptide Leu49-Thr76(Phe52,53 → Ala) revealed morphological change only at the nucleoids. Therefore peptide Leu49-Thr76 appears to primarily target the cytoplasm rather than the membrane of E. coli cells.

1999 ◽  
Vol 342 (1) ◽  
pp. 215 ◽  
Author(s):  
Mitsuyoshi MOTIZUKI ◽  
Takehito ITOH ◽  
Takanori SATOH ◽  
Sadaki YOKOTA ◽  
Muneo YAMADA ◽  
...  

2019 ◽  
Vol 10 ◽  
pp. 1864-1872
Author(s):  
Prof. Teodora P. Popova

The effect of ionized aqueous solutions (anolytes and catholyte) in the processing of fruits (cherries, morellos, and strawberries) for decontamination has been tested. Freshly prepared analytes and catholyte without the addition of salts were used, as well as stored for 7 months anolytes, prepared with 0.5% NaCl and a combination of 0.5% NaCl and 0.5% Na2CO3. The anolyte prepared with a combination of 0.5% NaCl and 0.5% Na2CO3, as well as the anolyte obtained with 0.5% NaCl, exhibit high antimicrobial activity against the surface microflora of strawberries, cherries, and sour cherries. They inactivate E. coli for 15 minutes. The other species of the fam. Enterobacteriaceae were also affected to the maximum extent, as is the total number of microorganisms, especially in cherries and sour cherries. Even stored for 7 months, they largely retain their antimicrobial properties. Anolyte and catholyte, obtained without the addition of salts, showed a lower effect on the total number of microorganisms, but had a significant effect on Gram-negative bacteria, and especially with regard to the sanitary indicative E. coli.


2019 ◽  
Vol 41 part 3 (2) ◽  
pp. 45-50
Author(s):  
O. A. Viltsaniuk ◽  
P. V. Belyaev ◽  
T. P. Osolodchenko ◽  
O. O. Viltsaniuk

Introduction. The problem of purulent-inflammatory processes treatment and the prevention of sepsis remains one of the most pressing problems of surgery.Purpose of the study. Is to estimate the effectiveness of sorption composition with antimicrobial properties on the basis of nanodisperse silica on the adhesive properties of microorganisms and to substantiate the expediency of its use for the purulent and inflammatory processes treatment and prevention of sepsis.Materials and methods.To determine the antimicrobial activity and the influence of the antiseptics of decasan, myramistin, ethonium, chlorhexidine and the sorption on the microorganisms adhesion properties composition was used the method of diffusion in agar of the museum strains of microorganisms S. Aureus ATCC 25923, E. Coli ATCC 25922, R. Vulgaris 4636, R. Aureginosa ATCC 27853, S. AIbicans 855/653, SI. Perfringens 28, Peptostreptococcus anaerobicus 22, Bacteroides fragilis 13/83, and clinical strains of S. Aureus, R. Aeuroginosa, E. Coli. Adhesive properties of microorganisms were studied according to the Brillis method et al. (1986) with the subsequent statistical processing of the data.Results. Studies have shown that antiseptics have high antimicrobial activity and reduce the adhesion ability of microorganisms. But the use of only antiseptics or only antibiotics for the purification of purulent foci can lead to toxins absorption and tissue decay products from purulent foci. That processes could be the trigger mechanism for sepsis development. The sorption composition is able to reduce the adhesive activity of bacteria, allows to absorb toxic substances from pathological foci, what preventing their resorption and thereby prevent the development of sepsis.Conclusions. The composition made from sorbents and antiseptics is not inferior to antimicrobial activity to antiseptics, which can reduce the virulence of bacteria, by reducing their adhesive activity, and absorb toxins of microorganisms and tissue decomposition products on their surface, thus prevent their absorption, which will prevent the purulent-inflammatory process progression and sepsis development.Keywords: sorption composition, nanodisperse silica, antiseptics, adhesive properties of microorganisms, prevention of sepsis.


2019 ◽  
Vol 947 ◽  
pp. 13-20
Author(s):  
Jem Valerie D. Perez ◽  
Joy Vanessa D. Perez ◽  
Raniv D. Rojo ◽  
Maria Lourdes P. Dalida ◽  
Debora F. Rodrigues

Bacterial proliferation and biofilm formation has emerged as a significant concern in the long-term use of industrial apparatus. This study describes the antimicrobial properties of a novel chitosan-polyethyleneimine-graphene oxide (CS-PEI-GO) nanocomposite against E. coli. The nanocomposite is a stable material with minimal dispersibility in storage water after more than 7 days. The antimicrobial activity is contact-time-dependent, with direct contact (92% bacterial inactivation after 3h exposure) having superior results compared with dynamic contact (~50% inactivation after 3h exposure). In addition, the incorporation of GO also translated to enhanced production of ROS—oxidation of GSH was higher in CS-PEI-GO (31.78%) as compared to CS-PEI alone (5.69%). This may be attributed to previously proposed mechanisms of mechanical membrane damage and reactive oxygen species production that may be more pronounced with prolonged contact. This may be due to the positively charged chitosan and the negatively charged cell membrane facilitating the coating of cells that could allow the oxygen-containing functional groups of GO to induce oxidative stress and lead to cell death.


2020 ◽  
Vol 307 ◽  
pp. 217-222 ◽  
Author(s):  
Maishara Syazrinni Rooshde ◽  
Wan Rafizah Wan Abdullah ◽  
Amie Zaidah Amran ◽  
Noradhiha Farahin Ibrahim ◽  
Fazilah Ariffin ◽  
...  

Biofouling and biofilms exist as ubiquitous, undesirable accumulation of flora and fauna upon a given substrate when being immersed into an aquatic medium. Therefore, a novel antifouling based materials with the incorporation of nanotechnology has been developed for the prevention of biofouling in its initial stage through photocatalytic treatment. This study investigated the antimicrobial properties of photoactive Cerium (Ce) doped ZnO powder and explores its potential properties for future antifouling application. ZnO nanoparticles was doped with 0.4 mol% Ce was synthesized through the combination of modified citrate gelation technique and solid state sintering. The successful preparation of Ce doped ZnO was confirmed by XRD and SEM. The antimicrobial activity of Ce doped ZnO against E. coli and S. aureus was determined through antibacterial susceptibility test by agar well diffusion method whilst its photocatalytic inactivation efficiency against selected bacteria was analysed through photodegradation testing under UV light irradiation. The findings demonstrated that the synthesized Ce doped ZnO powder exhibited antibacterial effect against Gram-positive bacteria (S. aureus) and excellent photocatalytic efficiency to inactivate both Gram-negative (E. coli) and Gram-positive (S. aureus). 2 g/L of Ce doped ZnO catalyzed the 100% disinfection of both bacteria in 180 min of UV light exposure. Thus, this proved that Ce doped ZnO powder has the potential as efficient antifouling agent.


2020 ◽  
Vol 8 (5) ◽  
pp. 780
Author(s):  
Armando Navarro ◽  
Delia Licona-Moreno ◽  
Alejandro Monsalvo-Reyes ◽  
Ulises Hernández-Chiñas ◽  
Carlos A. Eslava-Campos

Background: Escherichia coli and Salmonella are etiologic agents of intestinal infections. A previous study showed the presence of shared epitopes between lipopolysaccharides (LPSs) of E. coli O157 and Salmonella. Aim: Using phage display, the aim of this study is to identify mimotopes of shared epitopes in different enterobacterial LPSs. Methods: We use anti-LPS IgG from E. coli O157 and Salmonella to select peptide mimotopes of the M13 phage. The amino acid sequence of the mimotopes is used to synthesize peptides, which are in turn used to immunize rabbits. The antibody response of the resulting sera against the LPSs and synthetic peptides (SPs) is analyzed by ELISA and by Western blot assays, indicating that LPS sites are recognized by the same antibody. In a complementary test, the reactions of human serum samples obtained from the general population against the SPs and LPSs are also analyzed. Results: From the last biopanning phase, sixty phagotopes are selected. The analysis of the peptide mimotope amino acid sequences shows that in 4 of them the S/N/A/PF motif is a common sequence. Antibodies from the sera of immunized rabbits with SP287/3, SP459/1, SP308/3, and SP073/14 react against both their own peptide and the different LPSs. The Western blot test shows a sera reaction against both the lateral chains and the cores of the LPSs. The analysis of the human sera shows a response against the SPs and LPSs. Conclusion: The designed synthetic peptides are mimotopes of LPS epitopes of Salmonella and E. coli that possess immunogenic capacity. These mimotopes could be considered for use in the design of vaccines against both enterobacteria.


Nanomaterials ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 506 ◽  
Author(s):  
Kelly J. Figueroa-Lopez ◽  
Sergio Torres-Giner ◽  
Daniela Enescu ◽  
Luis Cabedo ◽  
Miguel A. Cerqueira ◽  
...  

This research reports about the development by electrospinning of fiber-based films made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) derived from fermented fruit waste, so-called bio-papers, with enhanced antimicrobial performance. To this end, different combinations of oregano essential oil (OEO) and zinc oxide nanoparticles (ZnONPs) were added to PHBV solutions and electrospun into mats that were, thereafter, converted into homogeneous and continuous films of ~130 μm. The morphology, optical, thermal, mechanical properties, crystallinity, and migration into food simulants of the resultant PHBV-based bio-papers were evaluated and their antimicrobial properties were assessed against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in both open and closed systems. It was observed that the antimicrobial activity decreased after 15 days due to the release of the volatile compounds, whereas the bio-papers filled with ZnONPs showed high antimicrobial activity for up to 48 days. The electrospun PHBV biopapers containing 2.5 wt% OEO + 2.25 wt% ZnONPs successfully provided the most optimal activity for short and long periods against both bacteria.


Molecules ◽  
2017 ◽  
Vol 22 (3) ◽  
pp. 452 ◽  
Author(s):  
Nataly Huertas Méndez ◽  
Yerly Vargas Casanova ◽  
Anyelith Gómez Chimbi ◽  
Edith Hernández ◽  
Aura Leal Castro ◽  
...  

2020 ◽  
Vol 21 (4) ◽  
Author(s):  
Siti Samiyarsih ◽  
NUR FITRIANTO ◽  
ELLY PROKLAMASININGSIH ◽  
JUWARNO ◽  
JUNI SAFITRI MULJOWATI

Abstract. Samiyarsih S, Fitrianto N, Proklamasiningsih E, Juwarno, Muljowati JS. 2020. Phytochemical diversity and antimicrobial properties of methanol extract of several cultivars of Catharanthus roseus using GC-MS. Biodiversitas 21: 1332-1344. Catharanthus roseus (L.) G is an important medicinal plant to evaluate the possibility of novel pharmaceuticals since most of the bacterial pathogens are developing resistance against antibiotics. This research aimed to determine the phytochemical diversity of methanol extract of eight cultivars of C. roseus and to evaluate for possible antimicrobial (antifungal and antibacterial) activities. It is the first research to compare phytochemicals and antimicrobial potential among C. roseus cultivars. The compound obtained was screened by Gas Chromatography-Mass Spectrometry (GC-MS) method. While agar-well disc diffusion method was employed to measure antimicrobial activity against Escherichia coli, Staphylococcus aureus, Aspergillus flavus and Aspergillus niger. Based on GC-MS analysis, a total of 18 significantly different metabolite compounds. The abundances of phytochemical compounds (18 classes total) in each cultivar were Dark Pink (66%), Pink (50%), Purple Pink (44%), Pale Pink (27%), White (44%), Milky White (50%), Whitish pink (50%) and Pinkish Red (55%). The leaves extracts showed antimicrobial activity with inhibition zones ranging from 6.40-22.00 mm and 3.35-8.20 mm, respectively. The best antimicrobial activity against E. coli, S. aureus, A. flavus, and A. niger with the zone of inhibition 16.10±1.67 mm, 22.00±0.33 mm, 6.05±0.67 mm and 8.20±0.50 mm respectively by Dark Pink cultivar.


Foods ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 442 ◽  
Author(s):  
Fabio Fontecha-Umaña ◽  
Abel Guillermo Ríos-Castillo ◽  
Carolina Ripolles-Avila ◽  
José Juan Rodríguez-Jerez

Food contact surfaces are primary sources of bacterial contamination in food industry processes. With the objective of preventing bacterial adhesion and biofilm formation on surfaces, this study evaluated the antimicrobial activity of silver (Ag-NPs) and zinc oxide (ZnO-NPs) nanoparticle-containing polyester surfaces (concentration range from 400 ppm to 850 ppm) using two kinds of bacteria, Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli), and the prevention of bacterial biofilm formation using the pathogen Listeria monocytogenes. The results of antimicrobial efficacy (reductions ≥ 2 log CFU/cm2) showed that at a concentration of 850 ppm, ZnO-NPs were effective against only E. coli (2.07 log CFU/cm2). However, a concentration of 400 ppm of Ag-NPs was effective against E. coli (4.90 log CFU/cm2) and S. aureus (3.84 log CFU/cm2). Furthermore, a combined concentration of 850 ppm Ag-NPs and 400 ppm ZnO-NPs showed high antimicrobial efficacy against E. coli (5.80 log CFU/cm2) and S. aureus (4.11 log CFU/cm2). The results also showed a high correlation between concentration levels and the bacterial activity of Ag–ZnO-NPs (R2 = 0.97 for S. aureus, and R2 = 0.99 for E. coli). They also showed that unlike individual action, the joint action of Ag-NPs and ZnO-NPs has high antimicrobial efficacy for both types of microorganisms. Moreover, Ag-NPs prevent the biofilm formation of L. monocytogenes in humid conditions of growth at concentrations of 500 ppm. Additional studies under different conditions are needed to test the durability of nanoparticle containing polyester surfaces with antimicrobial properties to optimize their use.


Sign in / Sign up

Export Citation Format

Share Document