Mechanisms involved in effects of antimicrobial peptides, bactenectins ChBac3.4, ChBac5, and mini-ChBac7.5Nb, on bacterial cells

2017 ◽  
pp. 43-50
Author(s):  
О.В. Шамова ◽  
М.С. Жаркова ◽  
П.М. Копейкин ◽  
Д.С. Орлов ◽  
Е.А. Корнева
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Innate Immunity ◽  
Infectious Diseases ◽  
Metabolic Activity ◽  
Capra Hircus ◽  
Bacterial Cells ◽  
Antibiotic Resistant ◽  
Resistant Strains

Антимикробные пептиды (АМП) системы врожденного иммунитета - соединения, играющие важную роль в патогенезе инфекционных заболеваний, так как обладают свойством инактивировать широкий спектр патогенных бактерий, обеспечивая противомикробную защиту живых организмов. В настоящее время АМП рассматриваются как потенциальные соединения-корректоры инфекционной патологии, вызываемой антибиотикорезистентными бактериями (АБР). Цель данной работы состояла в изученим механизмов антибактериального действия трех пептидов, принадлежащих к семейству бактенецинов - ChBac3.4, ChBac5 и mini-ChBac7.5Nb. Эти химически синтезированные пептиды являются аналогами природных пролин-богатых АМП, обнаруженных в лейкоцитах домашней козы Capra hircus и проявляющих высокую антимикробную активность, в том числе и в отношении грамотрицательных АБР. Методы. Минимальные ингибирующие и минимальные бактерицидные концентрации пептидов (МИК и МБК) определяли методом серийных разведений в жидкой питательной среде с последующим высевом на плотную питательную среду. Эффекты пептидов на проницаемость цитоплазматической мембраны бактерий для хромогенного маркера исследовали с использованием генетически модифицированного штамма Escherichia coli ML35p. Действие бактенецинов на метаболическую активность бактерий изучали с применением маркера резазурина. Результаты. Показано, что все исследованные пептиды проявляют высокую антимикробную активность в отношении Escherichia coli ML35p и антибиотикоустойчивых штаммов Escherichia coli ESBL и Acinetobacter baumannii in vitro, но их действие на бактериальные клетки разное. Использован комплекс методик, позволяющих наблюдать в режиме реального времени динамику действия бактенецинов в различных концентрациях (включая их МИК и МБК) на барьерную функцию цитоплазматической мембраны и на интенсивность метаболизма бактериальных клеток, что дало возможность выявить различия в характере воздействия бактенецинов, отличающихся по структуре молекулы, на исследуемые микроорганизмы. Установлено, что действие каждого из трех исследованных бактенецинов в бактерицидных концентрациях отличается по эффективности нарушения целостности бактериальных мембран и в скорости подавления метаболизма клеток. Заключение. Полученная информация дополнит существующие фундаментальные представления о механизмах действия пролин-богатых пептидов врожденного иммунитета, а также послужит основой для биотехнологических исследований, направленных на разработку на базе этих соединений новых антибиотических препаратов для коррекции инфекционных заболеваний, вызываемых АБР и являющимися причинами тяжелых внутрибольничных инфекций. Antimicrobial peptides (AMPs) of the innate immunity are compounds that play an important role in pathogenesis of infectious diseases due to their ability to inactivate a broad array of pathogenic bacteria, thereby providing anti-microbial host defense. AMPs are currently considered promising compounds for treatment of infectious diseases caused by antibiotic-resistant bacteria. The aim of this study was to investigate molecular mechanisms of the antibacterial action of three peptides from the bactenecin family, ChBac3.4, ChBac5, and mini-ChBac7.5Nb. These chemically synthesized peptides are analogues of natural proline-rich AMPs previously discovered by the authors of the present study in leukocytes of the domestic goat, Capra hircus. These peptides exhibit a high antimicrobial activity, in particular, against antibiotic-resistant gram-negative bacteria. Methods. Minimum inhibitory and minimum bactericidal concentrations of the peptides (MIC and MBC) were determined using the broth microdilution assay followed by subculturing on agar plates. Effects of the AMPs on bacterial cytoplasmic membrane permeability for a chromogenic marker were explored using a genetically modified strain, Escherichia coli ML35p. The effect of bactenecins on bacterial metabolic activity was studied using a resazurin marker. Results. All the studied peptides showed a high in vitro antimicrobial activity against Escherichia coli ML35p and antibiotic-resistant strains, Escherichia coli ESBL and Acinetobacter baumannii, but differed in features of their action on bacterial cells. The used combination of techniques allowed the real-time monitoring of effects of bactenecin at different concentrations (including their MIC and MBC) on the cell membrane barrier function and metabolic activity of bacteria. The differences in effects of these three structurally different bactenecins on the studied microorganisms implied that these peptides at bactericidal concentrations differed in their capability for disintegrating bacterial cell membranes and rate of inhibiting bacterial metabolism. Conclusion. The obtained information will supplement the existing basic concepts on mechanisms involved in effects of proline-rich peptides of the innate immunity. This information will also stimulate biotechnological research aimed at development of new antibiotics for treatment of infectious diseases, such as severe in-hospital infections, caused by antibiotic-resistant strains.

scholarly journals Study of the Effect of Carob (Ceratoniasiliqua L.) Extract Activity as Antibiotic from UTI

2018 ◽  
Vol 8 (1) ◽  
pp. 17-25
Author(s):  
Iman Fadhil Abdul-Husin
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Plant Extracts ◽  
Ethanol Extract ◽  
Species Level ◽  
Bacterial Cells ◽  
E Coli ◽  
In Vitro Antibacterial Activity ◽  
Resistant Strains

Escherichia coli  bacterial cells have been collected and selected from(30) patients (most found strain) in urine samples 25 (83.3 %) suffering from infection of urinary tract laid down in Hashimiyaha teaching hospital, Babylon during a period from Novembertwo thousand sixty to February two thousand seventy. The isolated strain  diagnosis is confirmed withVitek2 system apparatus which performed to identify species level ofEscherichia coli  isolates.To evaluate the antimicrobialaction of the ethanol extract of  Carob (CeratoniasiliquaL.) podsonlyas well as in mixture with certain drugs (64µg /ml ampicillin, 32µg /ml gentamicin, 128µg /ml amikacin,8µg /ml clindamycin.) as the wide usageantibiotics in the treatment of UTI bacterial infectionswhich has led to the emergence and spread of resistant strains. Many studies showed that the efficacy of antimicrobials can be improved by combining them with crude plant extracts. The antimicrobial activity of the ethanol extract of pods of Carob(CeratoniasiliquaL.)alone as well as in mixture with some  standard antimicrobials has been evaluated using well diffusion methodwhich demonstrates an in-vitro antibacterial activity of the tested extracts against E. Coli bacteria.  A combination of the tested extracts( concentration 100%,50%) with antibacterial has increased that activity of the tested antimicrobials.The results revealed the importance of  Carob plant extracts when associated with antibiotics to regulatorresistance E. Coli bacteria that developed as adanger to human health

scholarly journals In vitro Antimicrobial Activity of Acne Drugs Against Skin-Associated Bacteria

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mark A. T. Blaskovich ◽  
Alysha G. Elliott ◽  
Angela M. Kavanagh ◽  
Soumya Ramu ◽  
Matthew A. Cooper
Keyword(s):  
Antimicrobial Activity ◽  
Resistant Bacteria ◽  
Microbial Infection ◽  
Antibiotic Resistant ◽  
Drug Resistant Bacteria ◽  
Cutibacterium Acnes ◽  
Common Skin ◽  
Sebum Production ◽  
Resistant Strains

Abstract Acne is a common skin affliction that involves excess sebum production and modified lipid composition, duct blockage, colonization by bacteria, and inflammation. Acne drugs target one or more of these steps, with antibiotics commonly used to treat the microbial infection for moderate to severe cases. Whilst a number of other acne therapies are purported to possess antimicrobial activity, this has been poorly documented in many cases. We conducted a comparative analysis of the activity of common topical acne drugs against the principal etiological agent associated with acne: the aerotolerant anaerobic Gram-positive organism Propionibacterium acnes (recently renamed as Cutibacterium acnes). We also assessed their impact on other bacteria that could also be affected by topical treatments, including both antibiotic-sensitive and antibiotic-resistant strains, using broth microdilution assay conditions. Drugs designated specifically as antibiotics had the greatest potency, but lost activity against resistant strains. The non-antibiotic acne agents did possess widespread antimicrobial activity, including against resistant strains, but at substantially higher concentrations. Hence, the antimicrobial activity of non-antibiotic acne agents may provide protection against a background of increased drug-resistant bacteria.

scholarly journals Biological Properties of Structurally Related α-Helical Cationic Antimicrobial Peptides

1999 ◽  
Vol 67 (4) ◽  
pp. 2005-2009 ◽  
Author(s):  
Monisha G. Scott ◽  
Hong Yan ◽  
Robert E. W. Hancock
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Tumor Necrosis ◽  
Biological Properties ◽  
Cationic Antimicrobial Peptide ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Resistant Strains ◽  
Conventional Antibiotics ◽  
Necrosis Factor

ABSTRACT A series of α-helical cationic antimicrobial peptide variants with small amino acid changes was designed. Alterations in the charge, hydrophobicity, or length of the variant peptides did not improve the antimicrobial activity, and there was no statistically significant correlation between any of these factors and the MIC forPseudomonas aeruginosa, Escherichia coli, orSalmonella typhimurium. Individual peptides demonstrated synergy with conventional antibiotics against antibiotic-resistant strains of P. aeruginosa. The peptides varied considerably in the ability to bind E. coli O111:B4 lipopolysaccharide (LPS), and this correlated significantly with their antimicrobial activity and ability to block LPS-stimulated tumor necrosis factor and interleukin-6 production. In general, the peptides studied here demonstrated a broad range of activities, including antimicrobial, antiendotoxin, and enhancer activities.

scholarly journals Antibacterial Activity of Propolis Extracts from the Central Region of Romania against Neisseria gonorrhoeae

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 689
Author(s):  
Mihaela Laura Vică ◽  
Ioana Glevitzky ◽  
Mirel Glevitzky ◽  
Costel Vasile Siserman ◽  
Horea Vladi Matei ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Neisseria Gonorrhoeae ◽  
Simultaneous Detection ◽  
Inhibition Zone ◽  
Antibiotic Resistant ◽  
Sexually Transmitted ◽  
Strain Type ◽  
Resistant Strains ◽  
Common Infections

(1) Background: Sexually transmitted infections (STIs) are among the most common infections worldwide, many of these being caused by Neisseria gonorrhoeae (NG). Increased antimicrobial NG resistance has been reported in recent decades, highlighting the need for new sources of natural compounds with valuable antimicrobial activity. This study aims to determine the effect of propolis extracts on NG strains, including antibiotic-resistant strains. (2) Methods: First void urine samples from presumed positive STI subjects were harvested. DNA was extracted, purified, and amplified via PCR for the simultaneous detection of 6 STIs. The presence of the dcmH, gyrA, and parC genes was checked in the DNA samples from NG-positive patients. The antimicrobial activity of 5 aqueous propolis extracts from central Romania was investigated in vitro against some isolated NG strains. ANOVA tests were employed to assess differences and interactions between the inhibition zone for NG strains and propolis extracts. (3) Results: 7.07% of the patients presented NG infections, some strains being resistant or intermediate-resistant to ciprofloxacin. All propolis samples exhibited an antibacterial effect, including on resistant strains. (4) Conclusions: Statistical analysis demonstrated that the diameter of the inhibition zone was influenced both by the NG strain type and the source of the propolis extracts.

scholarly journals Sensitivity of antibiotic resistant coagulase-negative staphylococci to antiseptic piсloxydin in eye drops Vitabact

2020 ◽  
Author(s):  
Anait Khalatyan ◽  
Maria Budzinskaya ◽  
Ekaterina Kholina ◽  
Marina Strakhovskaya ◽  
Nadezhda Kolyshkina ◽  
...  
Keyword(s):  
High Efficiency ◽  
In Vitro Tests ◽  
Eye Drops ◽  
Bacterial Cells ◽  
Coagulase Negative Staphylococci ◽  
Destructive Effect ◽  
Antibiotic Resistant ◽  
Normal Microflora ◽  
Resistant Strains

Background. Coagulase-negative staphylococci (CNS), primarily Staphylococcus epidermidis, predominate in the normal microflora of the eye. However, due to irrational antibiotic therapy, resistant strains are widely distributed among CNS. Objective. To study the sensitivity of the antibiotic resistant CNS isolates to the antiseptic picloxydine dihydrochloride ("Vitabact"). Methods. Species, sensitivity to antibiotics and antiseptic picloxydine dihydrochloride were determined for 39 isolates of bacteria obtained from the conjunctival swabs. The cells morphology under the influence of antiseptic was studied by electron microscopy. Results. 33 isolates of S. epidermidis (17 sensitive or resistant to drugs of no more than 2 classes of antibiotics and 16 MDR), 2 S. haemolyticus (1 resistant to 2 classes of antibiotics and 1 MDR), 3 S. hominis (1 sensitive and 2 MDR), 1 S. caprae (MDR) were characterized. In vitro tests, the antiseptic picloxydine dihydrochloride showed high efficiency in suppressing the growth of staphylococci regardless of their sensitivity to antibiotics, as well as bactericidal activity at concentration of 31.2 g/ml. In this concentration, the antiseptic had a pronounced destructive effect on the surface structures of bacterial cells. Conclusion. Antiseptic picloxydine dihydrochloride is effective against antibiotic resistant coagulase-negative staphylococci.

scholarly journals The Use of Lavender (Lavandula angustifolia) Essential Oil as an Additive to Drinking Water for Broiler Chickens and Its In Vitro Reaction with Enrofloxacin

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1535
Author(s):  
M. Adaszyńska-Skwirzyńska ◽  
D. Szczerbińska ◽  
S. Zych
Keyword(s):  
Escherichia Coli ◽  
Drinking Water ◽  
Body Weight ◽  
Essential Oil ◽  
Water Consumption ◽  
Broiler Chickens ◽  
Lavender Oil ◽  
Resistant Strains ◽  
Synergistic Reaction

Biological activity of lavender essential oil is a property that can potentially find an application in poultry nutrition. Nowadays, the use of bioactive compounds is encouraged in many areas of industry and agriculture, since these substances have similar properties as withdrawn antibiotic growth promoters. Additionally, antibiotic resistance bacteria are one of the most important current threats to animal health. The purpose of the study was to determine the influence of lavender essential oil on the production parameters and blood parameters in broiler chickens and to assess the lavender oil’s in vitro reaction in a combination with enrofloxacin towards Escherichia coli. One-day-old non-sexed chicks (Ross 308) were divided into three experimental groups, each consisting of 100 individuals (five replicate of 20 boiler chicken each). The chickens in the control group received drinking water with no addition of lavender essential oil. In the experimental groups, lavender oil was added to the drinking water at a concentration of 0.4 mL/L, in the LEO1–42 from 1 to 42 days of age and the LEO22–42 group from the 22 to 42 days of age. The chickens’ body weight, feed consumption, water consumption, deaths and elimination due to health reasons were determined in the experiment. On day 42 of the chickens’ lives, blood samples were collected based on which selected parameters were identified. An in vitro experiment of lavender oil in combination with enrofloxacin was investigated with a checkerboard method. The results of the experiment showed the antimicrobial and antioxidant activity of lavender essential oil and its positive effect on the production results of broiler chickens. The study results proved that the addition of lavender oil positively impacted the chickens’ final body weight and feed conversion ratio (p < 0.01). No differences were observed between the groups for water consumption, death rate and the examined biochemical and immunological blood serum indices. Lavender essential oil was demonstrated to increase the blood serum’s total antioxidant status. A synergistic reaction in vitro was observed for lavender oil combined with enrofloxacin against resistant strains of Escherichia coli. Based on our study, a health-promoting effect of adding LEO to water for broiler chickens was found. Moreover, in vitro studies indicate a significant effect of lavender essential oil on the inhibition of the resistant strains of Escherichia coli growth and synergistic reaction with enrofloxacin.

scholarly journals Synergism of the Combination of Traditional Antibiotics and Novel Phenolic Compounds against Escherichia coli

Pathogens ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 811
Author(s):  
Md. Akil Hossain ◽  
Hae-Chul Park ◽  
Sung-Won Park ◽  
Seung-Chun Park ◽  
Min-Goo Seo ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Rattus Norvegicus ◽  
Inhibitory Concentration ◽  
Epicatechin Gallate ◽  
Antibiotic Resistant ◽  
E Coli ◽  
Pathogenic Escherichia Coli ◽  
Resistant Strains ◽  
Novel Approaches ◽  
Rapid Emergence

Pathogenic Escherichia coli (E. coli)-associated infections are becoming difficult to treat because of the rapid emergence of antibiotic-resistant strains. Novel approaches are required to prevent the progression of resistance and to extend the lifespan of existing antibiotics. This study was designed to improve the effectiveness of traditional antibiotics against E. coli using a combination of the gallic acid (GA), hamamelitannin, epicatechin gallate, epigallocatechin, and epicatechin. The fractional inhibitory concentration index (FICI) of each of the phenolic compound-antibiotic combinations against E. coli was ascertained. Considering the clinical significance and FICI, two combinations (hamamelitannin-erythromycin and GA-ampicillin) were evaluated for their impact on certain virulence factors of E. coli. Finally, the effects of hamamelitannin and GA on Rattus norvegicus (IEC-6) cell viability were investigated. The FICIs of the antibacterial combinations against E. coli were 0.281–1.008. The GA-ampicillin and hamamelitannin-erythromycin combinations more effectively prohibited the growth, biofilm viability, and swim and swarm motilities of E. coli than individual antibiotics. The concentration of hamamelitannin and GA required to reduce viability by 50% (IC50) in IEC-6 cells was 988.54 μM and 564.55 μM, correspondingly. GA-ampicillin and hamamelitannin-erythromycin may be potent combinations and promising candidates for eradicating pathogenic E. coli in humans and animals.

scholarly journals Komposisi Minyak Atsiri dan Aktivitas Antimikroba Rimpang Temu Putih dan Jahe Gajah sebagai Fitobiotik Pakan Unggas

2019 ◽  
Vol 6 (2) ◽  
pp. 181
Author(s):  
Laila Nur Rohma ◽  
Laila Nur Rohma ◽  
Osfar Sjofjan ◽  
M. Halim Natsir
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Essential Oil ◽  
Essential Oils ◽  
Feed Additives ◽  
Diffusion Method ◽  
Disc Diffusion ◽  
Activity Test ◽  
Main Component

ABSTRAK                                                                        Imbuhan pakan unggas dapat berasal dari bahan herbal yang mengandung berbagai komponen aktif yang bermanfaat bagi pertumbuhan ternak.Temu putih dan jahe gajah dapat dimanfaatkan sebagai imbuhan pakan karena mengandung minyak atsiri yang dapat berperan sebagai agen antibakteri. Penelitian ini bertujuan untuk mengetahui komponen penyusun minyak atsiri dan aktivitas antimikroba pada rimpang temu putih dan jahe gajah. Penelitian dilakukan dengan percobaan in vitro menggunakan temu putih dan jahe gajah yang diolah menjadi bentuk ekstrak minyak atsiri temu putih dan jahe gajah sebagai materi uji komposisi penyusun minyak atsiri serta bentuktepung dan enkapsulasi sebagai materi uji aktivitas antimikroba. Komposisi minyak atsiri temu putih terdiri dari lima komponen penyusun dengan cis-1,7-octadien-3-yl acetat sebagai komponen utama. Komposisi minyak atsiri jahe gajah terdiri dari tujuh komponen dan benzene,1-(1,5-dimethyl-4-hexenyl)-4-methyl-(CAS) ar-curcumene sebagai komponen utama. Minyak atsiri yang terkandung pada temu putih dan jahe gajah mempunyai peran dalam menghambat mikroba. Uji komposisi penyusun minyak atsiri menggunakan alat GC-MS dan uji aktivitas antimikroba menggunakan metode disc diffusion dan. Hasil dari uji aktivitas antimikroba menunjukkan bahwa temu putih dan jahe gajah dalam bentuk tepung dan enkapsulasi memiliki perbedaan yang sangat nyata (P<0,01) terhadap aktivitas antimikroba pada bakteri asam laktat, Escherichia coli dan Salmonella sp. Campuran temu putih dan jahe gajah (1:1) menunjukkan kemampuan terbaik dalam menghambat pertumbuhan bakteri patogen dengan diameter zona hambat 5,70±0,14 mm  (Escherichia coli) dan 6,88±0,45 mm (Salmonella sp.).Kata Kunci : antimikroba, fitobiotik, jahe gajah, minyak atsiri, temu putihABSTRACTThe poultry feed additives can contain herbal ingredients that contain various beneficial components for livestock growth. White turmeric and giant ginger can be used as feed additives because they contain essential oils that can be used as antibacterial agents. This study aims to determine the constituent components of essential oils and antimicrobial activity in white turmeric and giant ginger rhizomes. The study was carried out by in vitro experiments using white turmeric and giant ginger which were processed into the form of essential oil extract as material for the composition of essential oils test, and powder and encapsulation form as antimicrobial activity test material. The composition of essential oils of white turmeric consists of five constituent components with cis-1,7-octadien-3-yl acetate as the main component. The composition of giant ginger essential oil consists of seven components with benzene, 1- (1,5-dimethyl-4-hexenyl) -4-methyl- (CAS) ar-curcumene as the main component. Essential oils contained in the white turmeric and giant ginger have a role in inhibiting microbes. The composition of the essential oil tested using GC-MS and the antimicrobial activity test used the disc diffusion method. The results of the antimicrobial activity test showed that white turmeric and giant ginger in powder and encapsulation form had significant differences (P <0.01) on antimicrobial activity in lactic acid bacteria, Escherichia coli and Salmonella sp. The mixture of white turmeric and giant ginger (1: 1) showed the best ability to inhibit the growth of pathogenic bacteria with inhibitory zone diameters of 5.70 ± 0.14 mm (Escherichia coli) and 6.88 ± 0.45 mm (Salmonella sp.).Keywords: antimicrobial, essential oil, giant ginger, phytobiotic, white turmeric

Sign in / Sign up

Export Citation Format

Share Document