Modelling addition and replacement mechanisms of plasmid-based beta-lactam resistant E. coli infections

It is unknown whether antibiotic-resistant bacterial infections occur in addition to antibiotic-susceptible bacterial infections, thereby increasing the infection incidence, or whether they replace such infections, leaving total incidence unaffected. Observational longitudinal studies cannot separate both mechanisms. Using plasmid-based beta-lactam resistant E. coli as example, we applied a mathematical neutral null model to investigate whether biological mechanisms implying either a fitness cost or a benefit due to resistance lead to replacement or addition. Fitness costs cause resistant strains to die out if other strain characteristics are maintained equal. Under the assumptions tested, only increased virulence increases the total number of infections, while other of resistance lead to replacement without changing the total number of infections. As there is no biological evidence that plasmid-based beta-lactam resistance increases virulence, these findings suggest that the burden of disease is determined by attributable effects of resistance rather than by an increase in infections.

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

Pathogens ◽

10.3390/pathogens9100811 ◽

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.

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Beta-Lactam market research: Progress, challenges and prospects

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v11i3.2787 ◽

2020 ◽

Vol 11 (3) ◽

pp. 4879-4883

Author(s):

Bhavana B Bhat ◽

Pavithra Pradeep Prabhu ◽

Manisha Joshel Lobo ◽

Anusha ◽

Prathvi ◽

...

Keyword(s):

Market Share ◽

Bacterial Infections ◽

Pediatric Population ◽

Global Market ◽

Asia Pacific ◽

Research Progress ◽

Beta Lactam ◽

Drug Usage ◽

Capita Health Expenditure ◽

Resistant Strains

Antibiotics are robust medicines that are widely used from centuries together to treat bacterial infections such as UTI, Typhoid, and Cholera etc. The similarity between viral and bacterial infection has resulted in the misuse of these antibiotics, the result of which is the development of resistant strains. Such indiscriminate drug usage has been increasing in a vulnerable geriatric and pediatric population. The increase in per capita health expenditure has enhanced the global market of these class of drugs, and the scope is likely to shoot up in the coming years, paving the way for young investors to emerging. The Global market for antibiotics is highly competitive and has a large number of significant players dominating the market share. During the forecast period experts in the field have evaluated and segment to dominate in LAMEA (Latin America, Middle East and Africa) holding the majority of the Market share. However, Asia Pacific was found to be the highest region for contributing more revenues. Detailed market analysis for / was conducted by doing secondary research where the market segments were compared for antibiotics. The paper discusses several issues related to the area of medicines.

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Prevalence of antibiotic-resistant Escherichia coli isolated from urban and agricultural streams in Canterbury, New Zealand

FEMS Microbiology Letters ◽

10.1093/femsle/fnz104 ◽

2019 ◽

Vol 366 (8) ◽

Cited By ~ 2

Author(s):

Sophie Van Hamelsveld ◽

Muyiwa E Adewale ◽

Brigitta Kurenbach ◽

William Godsoe ◽

Jon S Harding ◽

...

Keyword(s):

Escherichia Coli ◽

New Zealand ◽

Pathogenic Bacteria ◽

Freshwater Ecosystems ◽

Urban Setting ◽

Antibiotic Resistant ◽

E Coli ◽

Mesophilic Bacteria ◽

Resistant Strains ◽

Population Counts

Abstract Baseline studies are needed to identify environmental reservoirs of non-pathogenic but associating microbiota or pathogenic bacteria that are resistant to antibiotics and to inform safe use of freshwater ecosystems in urban and agricultural settings. Mesophilic bacteria and Escherichia coli were quantified and isolated from water and sediments of two rivers, one in an urban and one in an agricultural area near Christchurch, New Zealand. Resistance of E. coli to one or more of nine different antibiotics was determined. Additionally, selected strains were tested for conjugative transfer of resistances. Despite having similar concentrations of mesophilic bacteria and E. coli, the rivers differed in numbers of antibiotic-resistant E. coli isolates. Fully antibiotic-susceptible and -resistant strains coexist in the two freshwater ecosystems. This study was the first phase of antibiotic resistance profiling in an urban setting and an intensifying dairy agroecosystem. Antibiotic-resistant E. coli may pose different ingestion and contact risks than do susceptible E. coli. This difference cannot be seen in population counts alone. This is an important finding for human health assessments of freshwater systems, particularly where recreational uses occur downstream.

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Thinking Outside the Bug: Molecular Targets and Strategies to Overcome Antibiotic Resistance

International Journal of Molecular Sciences ◽

10.3390/ijms20061255 ◽

2019 ◽

Vol 20 (6) ◽

pp. 1255 ◽

Cited By ~ 21

Author(s):

Ana Monserrat-Martinez ◽

Yann Gambin ◽

Emma Sierecki

Keyword(s):

Antibiotic Resistance ◽

Bacterial Infections ◽

Rational Design ◽

Disease Onset ◽

Resistant Bacteria ◽

Antibiotic Resistant ◽

New Antibiotics ◽

Resistant Strains ◽

Vancomycin Resistant ◽

Antibiotic Discovery

Since their discovery in the early 20th century, antibiotics have been used as the primary weapon against bacterial infections. Due to their prophylactic effect, they are also used as part of the cocktail of drugs given to treat complex diseases such as cancer or during surgery, in order to prevent infection. This has resulted in a decrease of mortality from infectious diseases and an increase in life expectancy in the last 100 years. However, as a consequence of administering antibiotics broadly to the population and sometimes misusing them, antibiotic-resistant bacteria have appeared. The emergence of resistant strains is a global health threat to humanity. Highly-resistant bacteria like Staphylococcus aureus (methicillin-resistant) or Enterococcus faecium (vancomycin-resistant) have led to complications in intensive care units, increasing medical costs and putting patient lives at risk. The appearance of these resistant strains together with the difficulty in finding new antimicrobials has alarmed the scientific community. Most of the strategies currently employed to develop new antibiotics point towards novel approaches for drug design based on prodrugs or rational design of new molecules. However, targeting crucial bacterial processes by these means will keep creating evolutionary pressure towards drug resistance. In this review, we discuss antibiotic resistance and new options for antibiotic discovery, focusing in particular on new alternatives aiming to disarm the bacteria or empower the host to avoid disease onset.

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Paper-based analytical devices for colorimetric detection of S. aureus and E. coli and their antibiotic resistant strains in milk

The Analyst ◽

10.1039/d0an01075h ◽

2020 ◽

Vol 145 (22) ◽

pp. 7320-7329

Author(s):

Muhammad Asif ◽

Fazli Rabbi Awan ◽

Qaiser Mahmood Khan ◽

Bongkot Ngamsom ◽

Nicole Pamme

Keyword(s):

Pathogenic Bacteria ◽

Colorimetric Detection ◽

Antibiotic Resistant ◽

Beta Lactamases ◽

E Coli ◽

Milk Samples ◽

Extended Spectrum Beta Lactamases ◽

Paper Microfluidic ◽

Resistant Strains ◽

Appropriate Prescription

We investigate paper microfluidic devices for detection of pathogenic bacteria and their sensitivity towards β-lactamase and Extended Spectrum Beta Lactamases (ESBLs) in milk samples to enable appropriate prescription of antibiotics for mastitis.

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Drug Resistance of Enterobacteriaceae Isolated from Chicken Carcasses

Journal of Food Protection ◽

10.4315/0362-028x-60.8.1001 ◽

1997 ◽

Vol 60 (8) ◽

pp. 1001-1005 ◽

Cited By ~ 4

Author(s):

MARIA A. TESSI ◽

MARIA S. SALSI ◽

MARIA I. CAFFER ◽

MARIA A. MOGUILEVSKY

Keyword(s):

Nalidixic Acid ◽

Processing Plant ◽

Antibiotic Resistant ◽

E Coli ◽

Resistance Patterns ◽

R Plasmids ◽

Resistant Strains ◽

Different Strains ◽

K 12 ◽

R Factors

The antibiotic resistance profiles and transferable R factors of Salmonella and Escherichia coli isolates from 104 broiler carcasses taken from one processing plant were determined. Carcasses were sampled after immersion chilling. All samples were transported iced and immediately analyzed upon arrival to the laboratory. The resistance patterns of isolates to 12 antibiotics were determined (i.e., ampicillin, cephalothin, streptomycin, sulfisoxazole, trim-ethoprim-sulfamethoxazole, nalidixic acid, tetracycline, neomycin, chloramphenicol, gentamicin, colistin, and nitrofurantoin). Isolates resistant to one or more antibiotics were utilized as donors of resistance to completely antibiotic-sensitive strains, an E. coli K-12, F−, J5, azide-resistant strain and a Salmonella serovar Enteritidis. Transfer of the different R plasmids was confirmed by the determination of the resistance patterns of the transconjugants. Of the 93 Salmonella and 71 E. coli strains isolated from these samples, the largest numbers were resistant to tetracycline (52.7% and 49.3%), sulfisoxazole (45.2% and 42.3%), and streptomycin (37.6% and 39.4%). Large percentages of the Salmonella (33.3%) and the E. coli (30.0%) strains transferred all or part of their resistance to E. coli K-12 in mixed cultures. Great variation was observed between different strains in the frequency at which they transferred resistance. Resistance to tetracycline, sulfisoxazole, and streptomycin was found to be conferred by 31.7%, 29.8%, and 21.6% of the 19 R factors identified. No transfer of resistance to nalidixic acid, gentamicin, cephalothin, nitrofurantoin, and chloramphenicol was detected. When 30 antibiotic-resistant E. coli strains were cultured with a sensitive strain of Salmonella serovar Enteritidis,7 (23.3%) of the resistant strains were found capable of transferring R factors. Only 2 (6.7%) of the resistant strains could transfer R factors and unusual β-galactosidase activity.

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Terminalia ferdinandiana Fruit and Leaf Extracts Inhibit Methicillin-Resistant Staphylococcus aureus Growth

Planta Medica ◽

10.1055/a-1013-0434 ◽

2019 ◽

Vol 85 (16) ◽

pp. 1253-1262 ◽

Cited By ~ 3

Author(s):

Matthew J. Cheesman ◽

Alan White ◽

Ben Matthews ◽

Ian E. Cock

Keyword(s):

Resistant Bacteria ◽

Leaf Extracts ◽

Antibiotic Resistant ◽

E Coli ◽

Growth Inhibitory ◽

Growth Inhibitory Activity ◽

Medicinal Use ◽

Spectrum Activity ◽

Resistant Strains ◽

Terminalia Ferdinandiana

AbstractThe development of multiple antibiotic–resistant bacteria has vastly depleted our repertoire of effective antibiotic chemotherapies. The development of multi-β-lactam-resistant strains are particularly concerning due to our previous reliance on this class of antibiotics because of their initial efficacy and broad-spectrum activity. With increases in extended-spectrum β-lactam-resistance and an expanded resistance to other classes of antibiotics, there is an urgent need for the development of effective new antibiotic therapies. Terminalia ferdinandiana is an endemic Australian plant known for its high antioxidant and tannin contents. T. ferdinandiana fruit and leaf extracts have strong antibacterial activity against a wide variety of bacterial pathogens. However, T. ferdinandiana extracts have not been tested against ESBL and MRSA antibiotic-resistant pathogens. An objective of this study was to screen T. ferdinandiana fruit and leaf extracts for bacterial growth inhibitory activity by disc diffusion assay against β-lactam-sensitive and -resistant E. coli strains and against methicillin-sensitive and -resistant S. aureus. The minimum inhibitory concentration (MIC) was quantified by liquid dilution techniques. The fruit methanolic extract, as well as the methanolic, aqueous, and ethyl acetate leaf extracts strongly inhibited the growth of the MRSA, with MICs as low as 223 µg/mL. In contrast, the extracts were ineffective inhibitors of ESBL growth. Metabolomic fingerprint analysis identified a diversity and relative abundance of tannins, flavonoids, and terpenoids, several of which have been reported to inhibit MRSA growth in isolation. All extracts were nontoxic in the Artemia nauplii and HDF toxicity assays, further indicating their potential for medicinal use.

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In Vitro and In Vivo Antibacterial Activities of SM-216601, a New Broad-Spectrum Parenteral Carbapenem

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.10.4185-4196.2005 ◽

2005 ◽

Vol 49 (10) ◽

pp. 4185-4196 ◽

Cited By ~ 27

Author(s):

Yutaka Ueda ◽

Katsunori Kanazawa ◽

Ken Eguchi ◽

Koji Takemoto ◽

Yoshiro Eriguchi ◽

...

Keyword(s):

Bacterial Infections ◽

Antibacterial Activities ◽

Multiresistant Pathogens ◽

E Coli ◽

Wide Range ◽

Agar Dilution ◽

Resistant Strains ◽

Mrsa Strains

ABSTRACT SM-216601 is a novel parenteral 1β-methylcarbapenem. In agar dilution susceptibility testing, the MIC of SM-216601 for 90% of the methicillin-resistant Staphylococcus aureus (MRSA) strains tested (MIC90) was 2 μg/ml, which was comparable to those of vancomycin and linezolid. SM-216601 was also very potent against Enterococcus faecium, including vancomycin-resistant strains (MIC90 = 8 μg/ml). SM-216601 exhibited potent activity against penicillin-resistant Streptococcus pneumoniae, ampicillin-resistant Haemophilus influenzae, Moraxella catarrhalis, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis, with MIC90s of less than 0.5 μg/ml, and intermediate activity against Citrobacter freundii, Enterobacter cloacae, Serratia marcescens, and Pseudomonas aeruginosa. The therapeutic efficacy of SM-216601 against experimentally induced infections in mice caused by S. aureus, E. faecium, E. coli, and P. aeruginosa reflected its in vitro activity and plasma level. Thus, SM-216601 is a promising candidate for nosocomial bacterial infections caused by a wide range of gram-positive and gram-negative bacteria, including multiresistant pathogens.

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Susceptibility of Antibiotic-Resistant and Antibiotic-Sensitive Foodborne Pathogens to Acid Anionic Sanitizers

Journal of Food Protection ◽

10.4315/0362-028x-61.10.1390 ◽

1998 ◽

Vol 61 (10) ◽

pp. 1390-1395 ◽

Cited By ~ 9

Author(s):

JOHN A. LOPES

Keyword(s):

Foodborne Pathogens ◽

Fruits And Vegetables ◽

Food Additives ◽

Attractive Alternative ◽

Gram Negative Bacteria ◽

Antibiotic Resistant ◽

Microbicidal Activity ◽

E Coli ◽

Bactericidal Efficacy ◽

Resistant Strains

Acid anionic sanitizers for treatment of fruits and vegetables were prepared using ingredients generally recognized as safe by the U.S. Food and Drug Administration or anionic surfactants and organic acid food additives. They met the regulatory definition as sanitizers by showing bactericidal efficacy of 99.999% in 30 s against Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 11229. These sanitizers showed a broad spectrum of microbicidal activity against both gram-positive and gram-negative bacteria. Antibiotic-sensitive and resistant strains of Listeria monocytogenes and Salmonella typhimurium were equally susceptible to these sanitizers. The acid anionic sanitizers showed microbicidal efficacy equal to that of hypochlorite against Aeromonas hydrophila, E. coli O157:H7, L. monocytogenes, Pseudomonas aeruginosa, S. typhimurium, and S. aureus. Unlike most other sanitizers, these agents do not covalently react with organic components of food; unlike cationic agents, they do not leave residues. The acid anionic sanitizers are prepared using stable, biodegradable, and nontoxic ingredients. Rapid microbicidal activity and the ease of storage, transportation, and use make these sanitizers an attractive alternative to hypochlorite for sanitizing fruits and vegetables.

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Biological Properties of Structurally Related α-Helical Cationic Antimicrobial Peptides

Infection and Immunity ◽

10.1128/iai.67.4.2005-2009.1999 ◽

1999 ◽

Vol 67 (4) ◽

pp. 2005-2009 ◽

Cited By ~ 103

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.

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