The Isolation of a Novel Streptomyces sp. CJ13 from a Traditional Irish Folk Medicine Alkaline Grassland Soil that Inhibits Multiresistant Pathogens and Yeasts

The World Health Organization recently stated that new sources of antibiotics are urgently required to stem the global spread of antibiotic resistance, especially in multiresistant Gram-negative bacteria. Although it was thought that many of the original sources of antibiotics were exhausted, innovative research has revealed promising new sources of antibiotic discovery in traditional medicine associated with Streptomyces. In this work we investigated the potential of a specific limestone grassland soil, associated with Irish folk medicine, as a new source of antimicrobial discovery. Using selective enrichment and isolation techniques on a limestone grassland soil sample obtained from Boho, West Fermanagh, we isolated Streptomyces sp. CJ13. This bacterium inhibited the growth of a broad range of pathogens in vitro including Gram positive Staphylococcus aureus (MRSA 43300) and Gram negative multiresistant Pseudomonas aeruginosa (PA01), as well as the anaerobic bacteria Propionibacterium acnes and the yeast Starmerella bombicola. Genome sequencing and phylogenetic analysis revealed Streptomyces sp. CJ13 to be closely related to an unclassified Streptomyces sp. MJM1172, Streptomyces sp. Mg1 and two species known as Streptomyces sp. ICC1 and ICC4 from a karst region in British Columbia. The closest type species to Streptomyces sp. CJ13 was Streptomyces lavendulae subspecies lavendulae. Analysis of Streptomyces sp. CJ13 whole genome sequence using the secondary metabolite prediction tool antiSMASH revealed similarities to several antibiotic gene synthesis clusters including salinichelin, mediomycin A, weishanmycin, combamide, heat stable antifungal factor and SAL-2242. These results demonstrate the potential of this alkaline grassland soil as a new resource for the discovery of a broad range of antimicrobial compounds including those effective against multiresistant Gram negative bacteria.

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Synthesis, In Vitro and In Silico Studies of Indolequinone Derivatives against Clinically Relevant Bacterial Pathogens

Current Topics in Medicinal Chemistry ◽

10.2174/1568026620666191223110518 ◽

2020 ◽

Vol 20 (3) ◽

pp. 192-208 ◽

Cited By ~ 1

Author(s):

Talita Odriane Custodio Leite ◽

Juliana Silva Novais ◽

Beatriz Lima Cosenza de Carvalho ◽

Vitor Francisco Ferreira ◽

Leonardo Alves Miceli ◽

...

Keyword(s):

In Silico ◽

Bacterial Infections ◽

Antimicrobial Agents ◽

Mass Spectrometry Analysis ◽

World Health ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Dione Derivative ◽

In Silico Studies

Background: According to the World Health Organization, antimicrobial resistance is one of the most important public health threats of the 21st century. Therefore, there is an urgent need for the development of antimicrobial agents with new mechanism of action, especially those capable of evading known resistance mechanisms. Objective: We described the synthesis, in vitro antimicrobial evaluation, and in silico analysis of a series of 1H-indole-4,7-dione derivatives. Methods: The new series of 1H-indole-4,7-diones was prepared with good yield by using a copper(II)- mediated reaction between bromoquinone and β-enamino ketones bearing alkyl or phenyl groups attached to the nitrogen atom. The antimicrobial potential of indole derivatives was assessed. Molecular docking studies were also performed using AutoDock 4.2 for Windows. Characterization of all compounds was confirmed by one- and two-dimensional NMR techniques 1H and 13C NMR spectra [1H, 13C – APT, 1H x 1H – COSY, HSQC and HMBC], IR and mass spectrometry analysis. Results: Several indolequinone compounds showed effective antimicrobial profile against Grampositive (MIC = 16 µg.mL-1) and Gram-negative bacteria (MIC = 8 µg.mL-1) similar to antimicrobials current on the market. The 3-acetyl-1-(2,5-dimethylphenyl)-1H-indole-4,7-dione derivative exhibited an important effect against different biofilm stages formed by a serious hospital life-threatening resistant strain of Methicillin-Resistant Staphylococcus aureus (MRSA). A hemocompatibility profile analysis based on in vitro hemolysis assays revealed the low toxicity effects of this new series. Indeed, in silico studies showed a good pharmacokinetics and toxicological profiles for all indolequinone derivatives, reinforcing their feasibility to display a promising oral bioavailability. An elucidation of the promising indolequinone derivatives binding mode was achieved, showing interactions with important sites to biological activity of S. aureus DNA gyrase. These results highlighted 3-acetyl-1-(2-hydroxyethyl)-1Hindole- 4,7-dione derivative as broad-spectrum antimicrobial prototype to be further explored for treating bacterial infections. Conclusion: The highly substituted indolequinones were obtained in moderate to good yields. The pharmacological study indicated that these compounds should be exploited in the search for a leading substance in a project aimed at obtaining new antimicrobials effective against Gram-negative bacteria.

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832. Assessment of Risk Factors Associated with Wide-resistance Gram-negative Bacteria Infections

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.1021 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S457-S457

Author(s):

Henry Pablo Lopes Campos e Reis ◽

Ana Beatriz Ferreira Rodrigues ◽

Julio César Castro Silva ◽

Lia Pinheiro de Lima ◽

Talita Lima Quinaher ◽

...

Keyword(s):

Risk Factors ◽

Mechanical Ventilation ◽

Univariate Analysis ◽

Multidrug Resistant ◽

University Hospital ◽

Gram Negative Bacteria ◽

Multiresistant Pathogens ◽

Gram Negative ◽

Contact Isolation ◽

Bladder Catheter

Abstract Background Enterobacteria and multidrug-resistant non-fermenting Gram-negative bacilli present a challenge in the management of invasive infections, leading to mortality rates due to their limited therapeutic arsenal. The objective of this work was to analyze risk factors that may be associated with these infections, for a better situational mapping and assertive decision-making in a university hospital in Brazil. Methods The study was conducted between January and September 2019, with 167 patients in contact isolation at a university hospital in Brazil. Potential outcome-related variables for wide-resistance Gram-negative bacteria (BGN) infections were evaluated. Risk factors were identified from univariate statistical analysis using Fisher’s test. Results 51 (30.5%) out of 167 patients in contact isolation evolved with wide-resistance BGN infection. Risk factors in univariate analysis were age, hospital unit and previous use of invasive devices. Patients aged up to 59 years were more likely to progress to infection than those aged over 60 years (p 0.0274, OR 2.2, 95% CI 1.1-4.5). Those admitted to the oncohematology (p < 0.001, OR 32.5, Cl 9.1-116.3) and intensive care unit (p < 0.001, OR 28.0, Cl 3.5-225.9) units were more likely to develop this type of infection. The least likely were those admitted to a kidney transplant unit (p 0.0034, OR 15.33, Cl 1.8-131.0). Prior use of mechanical ventilation (p 0.0058, OR 12.2, Cl 2.0-76.1) and delayed bladder catheter (p 0.0266, OR 5.0, Cl 1.2-20.1) in patients with respiratory and urinary tract infection, respectively, were also reported as risk factors related to these infections. The gender of the patients was not significant for the study. Conclusion This study determined that variables such as age, hospitalization unit, use of mechanical ventilation and delayed bladder catheter could be considered important risk factors in triggering the infectious process by wide-resistant gram-negative bacteria. Thus, the analysis of these factors becomes a great foundation to prevent the development of multiresistant pathogens through prevention strategies, prophylaxis management and more targeted empirical therapies. Disclosures All Authors: No reported disclosures

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Val-Geninthiocin: Structure Elucidation and MSn Fragmentation of Thiopeptide Antibiotics Produced by Streptomyces sp. RSF18

Zeitschrift für Naturforschung B ◽

10.1515/znb-2008-1014 ◽

2008 ◽

Vol 63 (10) ◽

pp. 1223-1230 ◽

Cited By ~ 8

Author(s):

Imran Sajid ◽

Khaled A. Shaaban ◽

Holm Frauendorf ◽

Shahida Hasnain ◽

Hartmut Laatscha

Keyword(s):

Amino Acids ◽

Biological Activity ◽

Antifungal Activity ◽

Structure Elucidation ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Unusual Amino Acids ◽

Streptomyces Sp ◽

Gram Positive Bacteria ◽

Thiopeptide Antibiotics

AbstractVal-Geninthiocin (2), a new member of thiopeptide antibiotics, was isolated from the mycelium of Streptomyces sp. RSF18, along with the closely related geninthiocin (1) and the macrolide, chalcomycin. By intensive NMR and MS studies, Val-geninthiocin (2) was identified as desoxygeninthiocin, a thiopeptide, containing several oxazole and thiazole units and a number of unusual amino acids. Compound 2 shows potent activity against Gram-positive bacteria and minor antifungal activity, while it is not effective against Gram-negative bacteria or microalgae. Here we describe the fermentation, isolation and structure elucidation as well as the biological activity of 2.

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Metal-Based Nanoparticles as Antimicrobial Agents: An Overview

Nanomaterials ◽

10.3390/nano10020292 ◽

2020 ◽

Vol 10 (2) ◽

pp. 292 ◽

Cited By ~ 66

Author(s):

Elena Sánchez-López ◽

Daniela Gomes ◽

Gerard Esteruelas ◽

Lorena Bonilla ◽

Ana Laura Lopez-Machado ◽

...

Keyword(s):

Metal Nanoparticles ◽

Antimicrobial Agents ◽

Physicochemical Characterization ◽

Copper Oxide Nanoparticles ◽

Added Value ◽

World Health ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Development Of Resistance ◽

Different Types

Metal-based nanoparticles have been extensively investigated for a set of biomedical applications. According to the World Health Organization, in addition to their reduced size and selectivity for bacteria, metal-based nanoparticles have also proved to be effective against pathogens listed as a priority. Metal-based nanoparticles are known to have non-specific bacterial toxicity mechanisms (they do not bind to a specific receptor in the bacterial cell) which not only makes the development of resistance by bacteria difficult, but also broadens the spectrum of antibacterial activity. As a result, a large majority of metal-based nanoparticles efficacy studies performed so far have shown promising results in both Gram-positive and Gram-negative bacteria. The aim of this review has been a comprehensive discussion of the state of the art on the use of the most relevant types of metal nanoparticles employed as antimicrobial agents. A special emphasis to silver nanoparticles is given, while others (e.g., gold, zinc oxide, copper, and copper oxide nanoparticles) commonly used in antibiotherapy are also reviewed. The novelty of this review relies on the comparative discussion of the different types of metal nanoparticles, their production methods, physicochemical characterization, and pharmacokinetics together with the toxicological risk encountered with the use of different types of nanoparticles as antimicrobial agents. Their added-value in the development of alternative, more effective antibiotics against multi-resistant Gram-negative bacteria has been highlighted.

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Complete Genome Sequence of Streptomyces sp. Strain BSE7F, a Bali Mangrove Sediment Actinobacterium with Antimicrobial Activities

Genome Announcements ◽

10.1128/genomea.00618-18 ◽

2018 ◽

Vol 6 (26) ◽

Cited By ~ 1

Author(s):

Ira Handayani ◽

Shanti Ratnakomala ◽

Puspita Lisdiyanti ◽

Fahrurrozi ◽

Mohammad Alanjary ◽

...

Keyword(s):

Genome Sequence ◽

Complete Genome Sequence ◽

Complete Genome ◽

Antimicrobial Activities ◽

Mangrove Sediment ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Content Type ◽

Streptomyces Sp ◽

Gram Positive Bacteria

The strain Streptomyces sp. BSE7F, a novel Streptomyces strain isolated from Indonesian mangrove sediment, displays antimicrobial activities against Gram-positive bacteria, Gram-negative bacteria, and yeast.

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Bacteriology and Antibiotic Prescription Patterns in a Malawian Tertiary Hospital Burns Unit

10.1101/419713 ◽

2018 ◽

Author(s):

Stephen Kasenda ◽

Donnie Mategula ◽

Geoffrey Elihu Manda ◽

Tilinde Keith Chokotho

Keyword(s):

Antimicrobial Resistance ◽

Antibiotic Prescription ◽

World Health ◽

Gram Negative Bacteria ◽

Bacterial Isolates ◽

Gram Negative ◽

Prescription Patterns ◽

The World ◽

Resistance Patterns ◽

Burns Unit

ABSTRACTIntroductionInfections are responsible for up to 85% of deaths in patients with burn injuries. Proper management of infections in patients with burns requires knowledge of local microbial landscape and antimicrobial resistance patterns. Most burns units in low to middle income countries lack this data to guide patient management.Methods and resultsWe conducted a retrospective audit of adult (≥17 years) patient records admitted between at 1st June 2007 and May 2017 at Queen Elizabeth Central Hospital Burns unit in Blantyre Malawi with an index complaint of burn injury. Descriptive statistical analysis was performed to determine antibiotic prescription patterns, microbial isolates and antimicrobial resistance patterns on the 500 patient files that met the inclusion criteria. Cephalosporin’s and Penicillin’s constituted 72.3% of the 328 antibiotic prescriptions given to 212 patients and 84% of all prescriptions were potentially inappropriate. A total of 102 bacterial isolates were identified and a majority (30.4%; n=31) were resistant to Aminoglycosides and Aminocyclitols (23.5%; n=24); seconded by Penicillin’s at 19.6% (n=20). Pseudomonas, staphylococcus and streptococcus species constituted 36.1%, 25% and 16.7% of all resistant bacteria that were isolated and they were thus the most common bacterial isolates. Drug resistance was more common among gram negative bacteria (48.8% versus 26.2%) and a greater proportion of patients (74.1%) that had antibiotic sensitivity testing were affected by drug resistant gram negative bacteria which appear on the World Health Organisation list of priority pathogens.ConclusionThe results of our preliminary study point towards nosocomial gram negative bacteria which appear on the World Health Organisations list of priority pathogens as the more common sources of antibiotic resistance. This scenario is potentially driven by inappropriate antibiotic prescriptions as well as clinical and laboratory diagnostic imprecision in addition to the universally recognised post burn pathophysiological changes of hypermetabolism and immunosuppression. Improvements in the areas of antimicrobial stewardship, diagnostic capacity and burns related research are needed in order to achieve optimal therapeutic outcomes and resource utilisation.

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A Mini Review of Antibacterial Properties of ZnO Nanoparticles

Frontiers in Physics ◽

10.3389/fphy.2021.641481 ◽

2021 ◽

Vol 9 ◽

Cited By ~ 3

Author(s):

Sergey V. Gudkov ◽

Dmitriy E. Burmistrov ◽

Dmitriy A. Serov ◽

Maxim B. Rebezov ◽

Anastasia A. Semenova ◽

...

Keyword(s):

Zinc Oxide ◽

Zinc Oxide Nanoparticles ◽

Antibacterial Effect ◽

Antibacterial Properties ◽

World Health ◽

Oxide Nanoparticles ◽

Gram Negative Bacteria ◽

Gram Negative ◽

E Coli ◽

Antibacterial Potential

The development of antibiotic resistance of bacteria is one of the most pressing problems in world health care. One of the promising ways to overcome microbial resistance to antibiotics is the use of metal nanoparticles and their oxides. In particular, numerous studies have shown the high antibacterial potential of zinc oxide nanoparticles (ZnO-NP) in relation to gram-positive and gram-negative bacteria. This mini-review includes an analysis of the results of studies in recent years aimed at studying the antibacterial activity of nanoparticles based on zinc oxide. The dependence of the antibacterial effect on the size of the applied nanoparticles in relation to E. coli and S. aureus is given. The influence of various ways of synthesis of zinc oxide nanoparticles and the main types of modifications of NP-ZnO to increase the antibacterial efficiency are also considered.

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Chemical Profiling of Antimicrobial Metabolites from Halophilic Actinomycete Nocardiopsis_sp. Al-H10-1 (KF384482) Isolated from Alang, Gulf of Khambhat, India

10.1101/2021.06.12.448169 ◽

2021 ◽

Author(s):

Jignasha T. Thumar ◽

Nisha Trivedi

Keyword(s):

Drug Resistance ◽

Saline Water ◽

Multiple Drug Resistance ◽

World Health ◽

Multiple Drug ◽

Gram Negative Bacteria ◽

Antimicrobial Compounds ◽

Gram Positive ◽

Gram Negative ◽

Halophilic Actinomycete

The overuse of antibiotics has resulted in the development of drug resistant, a major problem in disease curing processes i.e. development of drug resistance. The World Health Organization (WHO) released its first list of the most concerning pathogens for human health in 2017 which suggested that there are total 12 bacterial families which have developed multiple drug resistance and for which novel antibiotics are required immediately (WHO 2017). There is a requirement to explore some novel compounds to overcome this issue. Thus our study aimed at exploration of marine actinomycetes as a valuable resource for novel products with antimicrobial properties. The halophilic actinomycete Nocardiopsis_sp. Al-H10-1 (KF384482) was isolated from saline water (20 m away from shore) of Alang coast (Gulf of Khambhat), Bhavnagar, Gujarat, India. The isolate Al-H10-1 was identified as Nocardiopsis sp. through rigorous morphological and cultural characteristics; the species was confirmed through 16s rRNA phylogenetic analysis. The antimicrobial potential of Nocardiopsis sp. Al-H10-1 was assessed against a range of Gram-positive and Gram-negative bacteria as well as three fungi, there it demonstrated antimicrobial activity against four Gram negative bacteria and one Gram positive bacteria. Further active antimicrobial compounds present in ethyl acetate extract was identified using Gas Chromatography-Mass Spectroscopy (GC-MS). GC-MS analysis showed the presence of 17 compounds which included antimicrobial compounds like 2, 4-bis (1, 1-dimethylethyl)-Phenol, Dibutyl phthalate as well as various types of alkanes and their derivatives.

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Recalibration of the Antimicrobial MIC

Journal of Clinical and Laboratory Research ◽

10.31579/2768-0487/021 ◽

2021 ◽

Vol 2 (4) ◽

pp. 01-02

Author(s):

Daniel Amsterdam

Keyword(s):

Antibiotic Resistance ◽

The United States ◽

World Health ◽

Gram Negative Bacteria ◽

Antibiotic Resistant ◽

Gram Negative ◽

Gram Positive Bacteria ◽

The World ◽

Health Organization ◽

Laboratory Assay

In 2009, the World health organization (WHO) referred to the problem of antibiotics and antibiotic resistance stating, “Antibiotic Resistance – one of the three greatest threats to human health.” In 2019 (i.e., just as the COVID-19 pandemic was evolving), more than 2.8 million antibiotic-resistant infections were identified in the United States, resulting in more than 35,000 deaths (CDC 2019). The initial laboratory assay which demonstrated the activity of an antibacterial compound was performed by Alexander Fleming. He showed that an extract from the mold, Penicillium rubens, could inhibit the growth of several species of Gram-positive bacteria – but not Gram-negative bacteria that were cross-streaked on agar against the diffused Penicillium compound.

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Antibacterial activity of phytopathogenic Streptomyces strains against bacteria associated to clinical diseases

Arquivos do Instituto Biológico ◽

10.1590/1808-1657000142020 ◽

2020 ◽

Vol 87 ◽

Author(s):

Alex Augusto Tomaseto ◽

Marcel Costa Alpiste ◽

Alessandra Figueiredo de Castro Nassar ◽

Suzete Aparecida Lanza Destéfano

Keyword(s):

Antibacterial Activity ◽

Clinical Importance ◽

Gram Negative Bacteria ◽

Positive Signal ◽

Nrps Gene ◽

Genus Streptomyces ◽

Gram Negative ◽

Streptomyces Sp ◽

Streptomyces Spp ◽

Biochemical Research

ABSTRACT: The genus Streptomyces is associated with the ability to produce and excrete a variety of bioactive compounds, such as antibiotic, antifungal and antiviral. Biological active polyketide and peptide compounds with applications in medicine, agriculture and biochemical research are synthesized by PKS-I and NRPS genes. The evaluation of the presence of these genes associated with the biosynthesis of secondary metabolites in different phytopathogenic Streptomyces strains were performed using degenerated primers. The positive signal was observed in 58/63 Streptomyces strains for NRPS gene, 43/63 for PKS-I, and for PKS-II all the 63 strains showed positive signal of amplification. These strains also were tested with double layer agar-well technique against bacterial with clinical importance, and it was possible to observe the Streptomyces spp. strains were able to inhibit the growth of 14, 20, 13 and 3 isolates Gram-positive and Gram-negative bacteria, Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 14579), Pseudomonas aeruginosa (ATCC 27853) and Escherichia coli (ATCC 11775) respectively. The Streptomyces sp. strains IBSBF 2019 and IBSBF 2397 showed antibacterial activity against all four bacteria-target tested.

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