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.

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 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 Integrated Bioinformatic Analyses and Immune Characterization of New Neisseria gonorrhoeae Vaccine Antigens Expressed during Natural Mucosal Infection

Vaccines ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 153 ◽  
Author(s):  
Tianmou Zhu ◽  
Ryan McClure ◽  
Odile B. Harrison ◽  
Caroline Genco ◽  
Paola Massari
Keyword(s):  
Neisseria Gonorrhoeae ◽  
Recombinant Expression ◽  
Selection Strategy ◽  
Antibiotic Resistant ◽  
Sexually Transmitted ◽  
Vaccine Antigens ◽  
Mucosal Infection ◽  
Associated Proteins

There is an increasingly severe trend of antibiotic-resistant Neisseria gonorrhoeae strains worldwide and new therapeutic strategies are needed against this sexually-transmitted pathogen. Despite the urgency, progress towards a gonococcal vaccine has been slowed by a scarcity of suitable antigens, lack of correlates of protection in humans and limited animal models of infection. N. gonorrhoeae gene expression levels in the natural human host does not reflect expression in vitro, further complicating in vitro-basedvaccine analysis platforms. We designed a novel candidate antigen selection strategy (CASS), based on a reverse vaccinology-like approach coupled with bioinformatics. We utilized the CASS to mine gonococcal proteins expressed during human mucosal infection, reported in our previous studies, and focused on a large pool of hypothetical proteins as an untapped source of potential new antigens. Via two discovery and analysis phases (DAP), we identified 36 targets predicted to be immunogenic, membrane-associated proteins conserved in N. gonorrhoeae and suitable for recombinant expression. Six initial candidates were produced and used to immunize mice. Characterization of the immune responses indicated cross-reactive antibodies and serum bactericidal activity against different N. gonorrhoeae strains. These results support the CASS as a tool for the discovery of new vaccine candidates.

scholarly journals Photoinactivation of Neisseria gonorrhoeae: A Paradigm-Changing Approach for Combating Antibiotic-Resistant Gonococcal Infection

2019 ◽  
Vol 220 (5) ◽  
pp. 873-881 ◽  
Author(s):  
Ying Wang ◽  
Raquel Ferrer-Espada ◽  
Yan Baglo ◽  
Xueping S Goh ◽  
Kathryn D Held ◽  
...  
Keyword(s):  
Public Health ◽  
Epithelial Cells ◽  
Neisseria Gonorrhoeae ◽  
Abundant Species ◽  
Gonococcal Infection ◽  
Antibiotic Resistant ◽  
Radiant Exposure ◽  
Vaginal Epithelial Cells ◽  
Resistant Strains

AbstractAntimicrobial resistance in Neisseria gonorrhoeae is a major issue of public health, and there is a critical need for the development of new antigonococcal strategies. In this study, we investigated the effectiveness of antimicrobial blue light (aBL; wavelength, 405 nm), an innovative nonpharmacological approach, for the inactivation of N. gonorrhoeae. Our findings indicated that aBL preferentially inactivated N. gonorrhoeae, including antibiotic-resistant strains, over human vaginal epithelial cells in vitro. Furthermore, no aBL-induced genotoxicity to the vaginal epithelial cells was observed at the radiant exposure used to inactivate N. gonorrhoeae. aBL also effectively inactivated N. gonorrhoeae that had attached to and invaded into the vaginal epithelial cells in their cocultures. No gonococcal resistance to aBL developed after 15 successive cycles of inactivation induced by subtherapeutic exposure to aBL. Endogenous aBL-activatable photosensitizing porphyrins in N. gonorrhoeae were identified and quantified using ultraperformance liquid chromatography, with coproporphyrin being the most abundant species in all N. gonorrhoeae strains studied. Singlet oxygen was involved in aBL inactivation of N. gonorrhoeae. Together, these findings show that aBL represents a potential potent treatment for antibiotic-resistant gonococcal infection.

scholarly journals In Vitro Antimicrobial Activity of the Siderophore Cephalosporin Cefiderocol against Acinetobacter baumannii Strains Recovered from Clinical Samples

Antibiotics ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1309
Author(s):  
Davide Carcione ◽  
Claudia Siracusa ◽  
Adela Sulejmani ◽  
Roberta Migliavacca ◽  
Alessandra Mercato ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Acinetobacter Baumannii ◽  
Inhibition Zone ◽  
Broth Microdilution ◽  
Large Variability ◽  
Gold Standard Method ◽  
Disk Diffusion Test ◽  
In Vitro Antimicrobial Activity ◽  
Broth Microdilution Method

Background: Cefiderocol is a siderophore cephalosporin that exhibits antimicrobial activity against most multi-drug resistant Gram-negative bacteria, including Enterobacterales, Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia. Methods: A total of 20 multidrug-resistant A. baumannii strains were isolated from 2020 to 2021, molecularly characterized and tested to assess the in vitro antibacterial activity of cefiderocol. Thirteen strains were carbapenem-hydrolysing oxacillinase OXA-23-like producers, while seven were non-OXA-23-like producers. Minimum inhibitory concentrations (MICs) were determined by broth microdilution, considered as the gold standard method. Disk diffusion test was also carried out using iron-depleted CAMHB plates for cefiderocol. Results: Cefiderocol MICs ranged from 0.5 to 1 mg/L for OXA-23-like non-producing A. baumannii strains and from 0.25 to >32 mg/L for OXA-23-like producers, using the broth microdilution method. Cefiderocol MIC90 was 8 mg/L. Diameter of inhibition zone of cefiderocol ranged from 18 to 25 mm for OXA-23-like non-producers and from 15 to 36 mm for OXA-23-like producers, using the diffusion disk method. A large variability and a low reproducibility were observed during the determination of diameter inhibition zone. Molecular characterization showed that all isolates presented the ISAba1 genetic element upstream the blaOXA-51. Among OXA-23-like non-producers, four were blaOXA-58 positive and two were negative for all the resistance determinants analyzed. Conclusions: Cefiderocol showed in vitro antimicrobial activity against both carbapenem-susceptible and non-susceptible A. baumannii strains, although some OXA-23-like producers were resistant. Further clinical studies are needed to consolidate the role of cefiderocol as an antibiotic against MDR A. baumannii.

scholarly journals In Vitro Antimicrobial Activity of Zodia (Evodia suaveolens) Leaf Extract on Pathogenic Agents Dragon Fruit Plant

Jurnal Biota ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 78-85
Author(s):  
Trio Ageng Prayitno ◽  
Nuril Hidayati
Keyword(s):  
Antimicrobial Activity ◽  
Leaf Extract ◽  
Plant Pathogens ◽  
Inhibition Zone ◽  
Diffusion Method ◽  
Leaf Extracts ◽  
Dragon Fruit ◽  
Fruit Plants ◽  
Pathogenic Agents

The use of antimicrobials from plant extracts has not been used optimally to control pathogenic agents in dragon fruit plants. The purpose of this research was to determine the antimicrobial activity of zodia (Evodia suaveolens) leaf extracts on pathogenic agents of dragon fruit plants in vitro. The research method is laboratory research with Completely Randomized Design (CRD). The antimicrobial concentrations of zodia (E. suaveolens) leaf extract used six types including 50%, 60%, 70%, 80%, 90%, and 100% with four replications. The research sample was the leaf of zodia (E. suaveolens), Pseudomonas aeruginosa and Fusarium oxysporum strain Malang. Test the antimicrobial activity of zodia (E. suaveolens) leaf extracts on the growth of P. aeruginosa and F. oxysporum using the disc-diffusion method and wells method. The research instrument was used the observation sheet of the diameter of inhibition zone indicated by the clear zone. The diameter of inhibition zone data were analyzed using the One Way ANOVA test. The results showed that the antimicrobial activity of zodia (E. suaveolens) leaf extract significantly inhibited the growth of P. aeruginosa and F. oxysporum (P <0.05). These results recommend zodia (E. suaveolens) leaf extract as an antimicrobial agent for dragon fruit plant pathogens.

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 Novel Trichomonacidal Spermicides

2011 ◽  
Vol 55 (9) ◽  
pp. 4343-4351 ◽  
Author(s):  
Ashish Jain ◽  
Nand Lal ◽  
Lokesh Kumar ◽  
Vikas Verma ◽  
Rajeev Kumar ◽  
...  
Keyword(s):  
Hela Cells ◽  
Trichomonas Vaginalis ◽  
Human Sperm ◽  
Content Type ◽  
Sexually Transmitted ◽  
Vaginal Microflora ◽  
Anaerobic Energy ◽  
Resistant Strains ◽  
New Compounds

ABSTRACTMetronidazole, the U.S. Food and Drug Administration-approved drug against trichomoniasis, is nonspermicidal and thus cannot offer pregnancy protection when used vaginally. Furthermore, increasing resistance ofTrichomonas vaginalisto 5-nitro-imidazoles is a cause for serious concern. On the other hand, the vaginal spermicide nonoxynol-9 (N-9) does not protect against sexually transmitted diseases and HIV in clinical situations but may in fact increase their incidence due to its nonspecific, surfactant action. We therefore designed dually active, nonsurfactant molecules that were capable of killingTrichomonas vaginalis(both metronidazole-susceptible and -resistant strains) and irreversibly inactivating 100% human sperm at doses that were noncytotoxic to human cervical epithelial (HeLa) cells and vaginal microflora (lactobacilli)in vitro. Anaerobic energy metabolism, cell motility, and defense against reactive oxygen species, which are key to survival of both sperm andTrichomonasin the host after intravaginal inoculation, depend crucially on availability of free thiols. Consequently, molecules were designed with carbodithioic acid moiety as the major pharmacophore, and chemical variations were incorporated to provide high excess of reactive thiols for interacting with accessible thiols on sperm andTrichomonas. We report here thein vitroactivities, structure-activity relationships, and safety profiles of these spermicidal antitrichomonas agents, the most promising of which was more effective than N-9 (the OTC spermicide) in inactivating human sperm and more efficacious than metronidazole in killingTrichomonas vaginalis(including metronidazole-resistant strain). It also significantly reduced the available free thiols on human sperm and inhibited the cytoadherence ofTrichomonason HeLa cells. Experimentallyin vitro, the new compounds appeared to be safer than N-9 for vaginal use.

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