Comparative Analysis of Antimicrobial Activities of Valinomycin and Cereulide, the Bacillus cereus Emetic Toxin

ABSTRACTCereulide and valinomycin are highly similar cyclic dodecadepsipeptides with potassium ionophoric properties. Cereulide, produced by members of theBacillus cereusgroup, is known mostly as emetic toxin, and no ecological function has been assigned. A comparative analysis of the antimicrobial activity of valinomycin produced byStreptomycesspp. and cereulide was performed at a pH range of pH 5.5 to pH 9.5, under anaerobic and aerobic conditions. Both compounds display pH-dependent activity against selected Gram-positive bacteria, includingStaphylococcus aureus,Listeria innocua,Listeria monocytogenes,Bacillus subtilis, andBacillus cereusATCC 10987. Notably,B. cereusstrain ATCC 14579 and the emeticB. cereusstrains F4810/72 and A529 showed reduced sensitivity to both compounds, with the latter two strains displaying full resistance to cereulide. Both compounds showed no activity against the selected Gram-negative bacteria. Antimicrobial activity against Gram-positive bacteria was highest at alkaline pH values, where the membrane potential (ΔΨ) is the main component of the proton motive force (PMF). Furthermore, inhibition of growth was observed in both aerobic and anaerobic conditions. Determination of the ΔΨ, using the membrane potential probe DiOC2(3) (in the presence of 50 mM KCl) in combination with flow cytometry, demonstrated for the first time the ability of cereulide to dissipate the ΔΨ in sensitive Gram-positive bacteria. The putative role of cereulide production in the ecology of emeticB. cereusis discussed.

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Synthesis and Evaluation of Antimicrobial and Cytotoxic Activity of Oxathiine-Fused Quinone-Thioglucoside Conjugates of Substituted 1,4-Naphthoquinones

Molecules ◽

10.3390/molecules25163577 ◽

2020 ◽

Vol 25 (16) ◽

pp. 3577

Author(s):

Yuri E. Sabutski ◽

Ekaterina S. Menchinskaya ◽

Ludmila S. Shevchenko ◽

Ekaterina A. Chingizova ◽

Artur R. Chingizov ◽

...

Keyword(s):

Antimicrobial Activity ◽

Cytotoxic Activity ◽

Antimicrobial Activities ◽

Biologically Active ◽

Hydroxyl Group ◽

Diffusion Method ◽

Gram Positive ◽

Gram Positive Bacteria ◽

High Cytotoxic Activity ◽

Derivatives Of

A series of new tetracyclic oxathiine-fused quinone-thioglycoside conjugates based on biologically active 1,4-naphthoquinones and 1-mercapto derivatives of per-O-acetyl d-glucose, d-galactose, d-xylose, and l-arabinose have been synthesized, characterized, and evaluated for their cytotoxic and antimicrobial activities. Six tetracyclic conjugates bearing a hydroxyl group in naphthoquinone core showed high cytotoxic activity with EC50 values in the range of 0.3 to 0.9 μM for various types of cancer and normal cells and no hemolytic activity up to 25 μM. The antimicrobial activity of conjugates was screened against Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus), Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli), and fungus Candida albicans by the agar diffusion method. The most effective juglone conjugates with d-xylose or l-arabinose moiety and hydroxyl group at C-7 position of naphthoquinone core at concentration 10 µg/well showed antimicrobial activity comparable with antibiotics vancomicin and gentamicin against Gram-positive bacteria strains. In liquid media, juglone-arabinosidic tetracycles showed highest activity with MIC 6.25 µM. Thus, a positive effect of heterocyclization with mercaptosugars on cytotoxic and antimicrobial activity for group of 1,4-naphthoquinones was shown.

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Effect of Lactose Monolaurate on Pathogenic and Nonpathogenic Bacteria

Applied and Environmental Microbiology ◽

10.1128/aem.07701-11 ◽

2012 ◽

Vol 78 (9) ◽

pp. 3465-3468 ◽

Cited By ~ 22

Author(s):

Ashwini Wagh ◽

Shujie Shen ◽

Fen Ann Shen ◽

Charles D. Miller ◽

Marie K. Walsh

Keyword(s):

Listeria Monocytogenes ◽

Antimicrobial Activities ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Content Type ◽

Gram Positive Bacteria ◽

Lactose Monolaurate

ABSTRACTThe antimicrobial activities of sucrose monolaurate and a novel ester, lactose monolaurate (LML), were tested. Gram-positive bacteria were more susceptible than Gram-negative bacteria to both esters. The minimal bactericidal concentrations of LML were 5 to 9.5 mM forListeria monocytogenesisolates and 0.2 to 2 mM forMycobacteriumisolates.

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Essential Oil of Galinsoga Parviflora Leaves from Colombia

Natural Product Communications ◽

10.1177/1934578x1000501129 ◽

2010 ◽

Vol 5 (11) ◽

pp. 1934578X1000501

Author(s):

Jorge A. Pino ◽

Mauricio Gaviria ◽

Juana Quevedo-Vega ◽

Laura García-Lesmes ◽

Clara E. Quijano-Celis

Keyword(s):

Staphylococcus Aureus ◽

Chemical Composition ◽

Essential Oil ◽

Bacillus Cereus ◽

Volatile Compounds ◽

Antimicrobial Activities ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Leaf Oil

The chemical composition of the volatile compounds from the leaves of Galinsoga parviflora Cav. (Asteraceae) from Colombia was studied by GC and GC/MS. Eighty-eight volatile compounds were identified, of which the major ones were (Z)-3-hexen-1-ol (21.7%), β-caryophyllene (12.4%), and 6-demethoxy-ageratochrome (14%). The leaf oil presented antimicrobial activities against the Gram-positive bacteria Staphylococcus aureus and Bacillus cereus.

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Antimicrobial activities of Antarctic sponges

Antarctic Science ◽

10.1017/s0954102092000270 ◽

1992 ◽

Vol 4 (2) ◽

pp. 179-183 ◽

Cited By ~ 20

Author(s):

J.B. McClintock ◽

J.J. Gauthier

Keyword(s):

Antimicrobial Activity ◽

Growth Inhibition ◽

Antimicrobial Activities ◽

Marine Sponges ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Strong Activity ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Antarctic Marine

Methanol-toluene extracts of 17 common Antarctic marine sponges collected from shallow waters in McMurdo Sound in October–December 1989 were tested for suppression of growth of bacteria (gram-positive and negative), yeasts and fungi. Weak to moderate levels of antimicrobial activity occurred in all sponges. Antimicrobial activity was more common when gram-negative bacteria were exposed to sponge extracts; 47% of the sponge extracts caused growth inhibition in one or more gram-positive bacteria, while 100% of the extracts caused growth inhibition in gram-negative bacteria. Particularly strong activity was observed against two species of gram-positive bacteria exposed to extracts of the sponge Latrunculia apicalis and against one strain of gram-negative bacterium exposed to extracts of the sponge Haliclona sp. Antimicrobial responses against yeasts and fungi were generally non-existent or weak, with the exception of the yeast Candida tropicalis, which was strongly inhibited by extracts of the sponges Homaxonella balfourensis, Dendrilla membranosa, Kirkpatrickia variolosa, Gellius benedeni, Cinachyra antarctica and Scolymastia joubinia. Antimicrobial activity in these polar sponges is widespread but generally weaker than that found in temperate and tropical sponges.

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Cerecidins, Novel Lantibiotics from Bacillus cereus with Potent Antimicrobial Activity

Applied and Environmental Microbiology ◽

10.1128/aem.03751-13 ◽

2014 ◽

Vol 80 (8) ◽

pp. 2633-2643 ◽

Cited By ~ 36

Author(s):

Jian Wang ◽

Li Zhang ◽

Kunling Teng ◽

Shutao Sun ◽

Zhizeng Sun ◽

...

Keyword(s):

Bacillus Cereus ◽

Multidrug Resistant ◽

Regulator Gene ◽

Gram Positive ◽

Content Type ◽

Pcr Screening ◽

Gram Positive Bacteria ◽

Immunity Genes ◽

Natural Variants ◽

Vancomycin Resistant

ABSTRACTLantibiotics are ribosomally synthesized and posttranslationally modified antimicrobial peptides that are widely produced by Gram-positive bacteria, including many species of theBacillusgroup. In the present study, one novel gene cluster coding lantibiotic cerecidins was unveiled inBacillus cereusstrain As 1.1846 through genomic mining and PCR screening. The designatedcerlocus is different from that of conventional class II lantibiotics in that it included seven tandem precursorcerAgenes, one modification gene (cerM), two processing genes (cerTandcerP), one orphan regulator gene (cerR), and two immunity genes (cerFandcerE). In addition, one unprecedented quorum sensing component,comQXPA, was inserted betweencerMandcerR. The expression of cerecidins was not detected in this strain ofB. cereus, which might be due to repressed transcription ofcerM. We constitutively coexpressedcerAgenes andcerMinEscherichia coli, and purified precerecidins were proteolytically processed with the endoproteinase GluC and a truncated version of putative serine protease CerP. Thus, two natural variants of cerecidins A1 and A7 were obtained which contained two terminal nonoverlapping thioether rings rarely found in lantibiotics. Both cerecidins A1 and A7 were active against a broad spectrum of Gram-positive bacteria. Cerecidin A7, especially its mutant Dhb13A, showed remarkable efficacy against multidrug-resistantStaphylococcus aureus(MDRSA), vancomycin-resistantEnterococcus faecalis(VRE), and evenStreptomyces.

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Nisin H Is a New Nisin Variant Produced by the Gut-Derived Strain Streptococcus hyointestinalis DPC6484

Applied and Environmental Microbiology ◽

10.1128/aem.00212-15 ◽

2015 ◽

Vol 81 (12) ◽

pp. 3953-3960 ◽

Cited By ~ 35

Author(s):

Paula M. O'Connor ◽

Eileen F. O'Shea ◽

Caitriona M. Guinane ◽

Orla O'Sullivan ◽

Paul D. Cotter ◽

...

Keyword(s):

Antimicrobial Activity ◽

Immune System ◽

Bacteriocin Production ◽

Genetic Determinants ◽

Gram Positive ◽

Content Type ◽

Gram Positive Bacteria ◽

Wide Range ◽

Similar Gene ◽

Strain Genome

ABSTRACTAccumulating evidence suggests that bacteriocin production represents a probiotic trait for intestinal strains to promote dominance, fight infection, and even signal the immune system. In this respect, in a previous study, we isolated from the porcine intestine a strain ofStreptococcus hyointestinalisDPC6484 that displays antimicrobial activity against a wide range of Gram-positive bacteria and produces a bacteriocin with a mass of 3,453 Da. Interestingly, the strain was also found to be immune to a nisin-producing strain. Genome sequencing revealed the genetic determinants responsible for a novel version of nisin, designated nisin H, consisting of thenshABTCPRKGEFgenes, with transposases encoded betweennshPandnshRand betweennshKandnshG. A similar gene cluster is also found inS. hyointestinalisLMG14581. Notably, the cluster lacks an equivalent of the nisin immunity gene,nisI. Nisin H is proposed to have the same structure as the prototypical nisin A but differs at 5 amino acid positions—Ile1Phe (i.e., at position 1, nisin A has Ile while nisin H has Phe), Leu6Met, Gly18Dhb (threonine dehydrated to dehydrobutyrine), Met21Tyr, and His31Lys—-and appears to represent an intermediate between the lactococcal nisin A and the streptococcal nisin U variant of nisin. Purified nisin H inhibits a wide range of Gram-positive bacteria, including staphylococci, streptococci,Listeriaspp., bacilli, and enterococci. It represents the first example of a natural nisin variant produced by an intestinal isolate of streptococcal origin.

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Synthesis and Antimicrobial Activities of 5-Arylidene-thiazolidine-2,4-dione Derivatives

BioMed Research International ◽

10.1155/2014/316082 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Ivanildo Mangueira da Silva ◽

João da Silva Filho ◽

Priscila Brandão Gomes da Silva Santiago ◽

Micalyne Soares do Egito ◽

Carlos André de Souza ◽

...

Keyword(s):

Antimicrobial Activity ◽

Bacterial Resistance ◽

Antimicrobial Activities ◽

Diffusion Method ◽

Resistant Bacteria ◽

Disc Diffusion Method ◽

Pharmacological Activities ◽

Gram Positive ◽

Gram Positive Bacteria ◽

Repeated Use

Antibiotic resistance is considered one of the world's major public health concerns. The main cause of bacterial resistance is the improper and repeated use of antibiotics. To alleviate this problem, new chemical substances against microorganisms are being synthesized and tested. Thiazolidines are compounds having many pharmacological activities including antimicrobial activities. For this purpose some thiazolidine derivatives substituted at position 5 in the thiazolidine nucleus were synthesized and tested against several microorganisms. Using a disc diffusion method, antimicrobial activity was verified against Gram-positive, Gram-negative, and alcohol acid resistant bacteria and yeast. The minimum inhibition concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined. All derivatives showed antimicrobial activity mainly against Gram-positive bacteria, with MIC values ranging from 2 to 16 µg/mL.

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The Mechanism of Action of Ginkgolic Acid (15:1) against Gram-Positive Bacteria Involves Cross Talk with Iron Homeostasis

Microbiology Spectrum ◽

10.1128/spectrum.00991-21 ◽

2022 ◽

Author(s):

Zewen Wen ◽

Yuxi Zhao ◽

Zhengyang Gong ◽

Yuanyuan Tang ◽

Yanpeng Xiong ◽

...

Keyword(s):

Antimicrobial Activity ◽

Natural Product ◽

Iron Homeostasis ◽

Multidrug Resistant ◽

Gram Positive ◽

Content Type ◽

Gram Positive Bacteria ◽

Ginkgolic Acid ◽

Wide Range ◽

Novel Antibiotics

The increasing emergence of infectious diseases associated with multidrug-resistant Gram-positive pathogens has raised the urgent need to develop novel antibiotics. GA (15:1) is a natural product derived from Ginkgo biloba and possesses a wide range of bioactivities, including antimicrobial activity.

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Three Novel Lantibiotics, Ticins A1, A3, and A4, Have Extremely Stable Properties and Are Promising Food Biopreservatives

Applied and Environmental Microbiology ◽

10.1128/aem.01851-15 ◽

2015 ◽

Vol 81 (20) ◽

pp. 6964-6972 ◽

Cited By ~ 10

Author(s):

Bingyue Xin ◽

Jinshui Zheng ◽

Ziya Xu ◽

Congzhi Li ◽

Lifang Ruan ◽

...

Keyword(s):

Bacillus Cereus ◽

Foodborne Pathogens ◽

Antimicrobial Activities ◽

Biochemical Properties ◽

Major Drawback ◽

Food Preservative ◽

Content Type ◽

Gram Positive Bacteria ◽

Potential Applications ◽

Over 40 Years

ABSTRACTLantibiotics are antimicrobial peptides with potential applications as the next generation of antimicrobials in the food industry and/or the pharmaceutical industry. Nisin has successfully been used as a food preservative for over 40 years, but its major drawback is its limited stability under neutral and alkaline pH conditions. To identify alternatives with better biochemical properties, we screened more than 100 strains of theBacillus cereusgroup. Three novel lantibiotics, ticins A1 (4,062.98 Da), A3 (4,048.96 Da), and A4 (4,063.02 Da), which were highly thermostable (121°C for 30 min) and extremely pH tolerant (pH 2.0 to 9.0), were identified inBacillus thuringiensisBMB3201. They all showed potent antimicrobial activities against all tested Gram-positive bacteria and greater activities than those of nisin A againstBacillus cereusandListeria monocytogenes, two important foodborne pathogens. These three novel lantibiotics, with their extremely stable properties and potent antimicrobial activities, have the potential for use as biopreservatives.

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Volatiles from Selected Apiaceae Species Cultivated in Poland—Antimicrobial Activities

Processes ◽

10.3390/pr9040695 ◽

2021 ◽

Vol 9 (4) ◽

pp. 695

Author(s):

Jaroslaw Widelski ◽

Konstantia Graikou ◽

Christos Ganos ◽

Krystyna Skalicka-Wozniak ◽

Ioanna Chinou

Keyword(s):

Antimicrobial Activity ◽

Essential Oils ◽

Antimicrobial Agents ◽

Antimicrobial Activities ◽

Gas Chromatography Mass Spectrometry ◽

Gram Positive ◽

Ongoing Research ◽

Gram Positive Bacteria ◽

Aerial Parts ◽

Bacteria And Fungi

As part of our ongoing research on phytoconstituents that can act as promising antimicrobial agents, the essential oils of nine selected Apiaceae plants, cultivated in Poland, were studied. The volatiles of the aerial parts with fruits (herba cum fructi) of Silaum silaus, Seseli devenyense, Seseli libanotis,Ferula assa-foetida, Glehnia littoralis and Heracleum dulce, in addition to the fruits (fructi) of Torilis japonica and Orlaya grandiflora as well as of the aerial parts (herba) of Peucedanum luxurians were investigated through Gas Chromatography–Mass Spectrometry to identify more than 60 different metabolites. The essential oils from S. devenyense, H. dulce, T. japonica and P. luxurians are reported for the first time. All examined species were also assayed for their antimicrobial activities against several human pathogenic Gram-positive and -negative bacteria and fungi. The species H. dulce, S. devenyense and S. libanotis exerted the strongest antimicrobial activity, mostly against Gram-positive bacteria strains (MIC values 0.90–1.20 mg/mL). To the best of our knowledge, this is the first attempt to determine the antimicrobial activity of the above Apiaceae species.

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