Emergence of Staphylococcus aureus Carrying Multiple Drug Resistance Genes on a Plasmid Encoding Exfoliative Toxin B

ABSTRACTWe report the complete nucleotide sequence and analysis of pETBTY825, aStaphylococcus aureusTY825 plasmid encoding exfoliative toxin B (ETB).S. aureusTY825 is a clinical isolate obtained from an impetigo patient in 2002. The size of pETBTY825, 60.6 kbp, was unexpectedly larger than that of the archetype pETBTY4(∼30 kbp). Genomic comparison of the plasmids shows that pETBTY825has the archetype pETBTY4as the backbone and has a single large extra DNA region of 22.4 kbp. The extra DNA region contains genes for resistance to aminoglycoside [aac(6′)/aph(2″)], macrolide (msrA), and penicillin (blaZ). A plasmid deletion experiment indicated that these three resistance elements were functionally active. We retrospectively examined the resistance profile of the clinical ETB-producingS. aureusstrains isolated in 1977 to 2007 using a MIC determination with gentamicin (GM), arbekacin (ABK), and erythromycin (EM) and by PCR analyses foraac(6′)/aph(2″) andmsrAusing purified plasmid preparations. The ETB-producingS. aureusstrains began to display high resistance to GM, which was parallel with the detection ofaac(6′)/aph(2″) andmecA, after 1990. Conversely, there was no significant change in the ABK MIC during the testing period, although it had a tendency to slightly increase. After 2001, isolates resistant to EM significantly increased; however,msrAwas hardly detected in ETB-producingS. aureusstrains, and only five isolates were positive for bothaac(6′)/aph(2″) andmsrA. In this study, we report the emergence of a fusion plasmid carrying the toxin geneetband drug resistance genes. Prevalence of the pETBTY825carrier may further increase the clinical threat, since ETB-producingS. aureusis closely related to more severe impetigo or staphylococcal scalded-skin syndrome (SSSS), which requires a general antimicrobial treatment.

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P133 Localization of resistance genes on the multiple-drug resistance plasmids in Escherichia coli isolated from beef cattle

International Journal of Antimicrobial Agents ◽

10.1016/s0924-8579(13)70377-7 ◽

2013 ◽

Vol 42 ◽

pp. S84

Author(s):

S. Yamamoto ◽

M. Nakano ◽

M. Tanaka ◽

W. Kitagawa ◽

T. Sone ◽

...

Keyword(s):

Escherichia Coli ◽

Drug Resistance ◽

Beef Cattle ◽

Resistance Genes ◽

Multiple Drug Resistance ◽

Multiple Drug ◽

Resistance Plasmids

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Relationship between multiple drug resistance and biofilm formation in Staphylococcus aureus isolated from medical and non-medical personnel in Yaounde, Cameroon

Pan African Medical Journal ◽

10.11604/pamj.2014.17.186.2363 ◽

2014 ◽

Vol 17 ◽

Cited By ~ 5

Author(s):

Agnes Bedie Eyoh ◽

Michel Toukam ◽

Julius Atashili ◽

Charles Fokunang ◽

Hortense Gonsu ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Drug Resistance ◽

Biofilm Formation ◽

Multiple Drug Resistance ◽

Medical Personnel ◽

Multiple Drug

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MRSA REMAINS A GREAT PRIORITY DUE TO THE TREMENDOUS MORTALITY --- A BIRD'S EYE VIEW

10.36106/gjra/0811782 ◽

2021 ◽

pp. 114-118

Author(s):

Raghavendra Rao M. V ◽

Mubasheer Ali ◽

Yogendra Kumar Verma ◽

Dilip Mathai ◽

Tina Priscilla ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Drug Resistance ◽

Chronic Infection ◽

Methicillin Resistant Staphylococcus Aureus ◽

Multiple Drug Resistance ◽

Multiple Drug ◽

High Dose ◽

Benzyl Penicillin ◽

Methicillin Resistant ◽

Antimicrobial Sensitivity

Methicillin-resistant Staphylococcus aureus (MRSA) is difcult to treat with methicillin, amoxicillin, penicillin, oxacillin, and other commonly used antibiotics because of its resistance. Staphylococcus organisms rapidly develop drug resistance as many as 50% of the domiciliary and 80% of the hospital strains are now penicillin resistant. Staphylococcus aureus also show multiple drug resistance. Therefore, Staphylococcal isolates should always be tested for antimicrobial sensitivity and chronic infection should be treated by more than one drug. Before 1960,when methicillin, is the rst penicillin's-resistant penicillin's, was brought into use, about 1%of the strains of the Staphylococcus aureus were "methicillin resistant" and by 1970 in Britain their proportion has risen to about 5%.These strains are tolerant of, low therapeutic concentrations of methicillin, cloxacillin, benzyl penicillin and ampicillin.They do not destroy methicillin and cloxacillin, but most of them are penicillinase-producing as well as being "methicillin resistant" and therefore inactivate benzyl penicillin and ampicillin. Its resistance is uncertain since infections may be cured with a high dose of methicillin.

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Inhibition of Antibiotic Efflux in Bacteria by the Novel Multidrug Resistance Inhibitors Biricodar (VX-710) and Timcodar (VX-853)

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.48.11.4171-4176.2004 ◽

2004 ◽

Vol 48 (11) ◽

pp. 4171-4176 ◽

Cited By ~ 56

Author(s):

Steve Mullin ◽

Nagraj Mani ◽

Trudy H. Grossman

Keyword(s):

Staphylococcus Aureus ◽

Drug Resistance ◽

Multiple Drug Resistance ◽

Antibiotic Activity ◽

Multiple Drug ◽

The Novel ◽

Multidrug Efflux ◽

New Class ◽

Clinically Significant ◽

Antibiotic Efflux

ABSTRACT Inhibitors of mammalian multidrug efflux, such as the plant alkaloid reserpine, are also active in potentiating antibiotic activity by inhibiting bacterial efflux. Based on this precedent, two novel mammalian multiple drug resistance inhibitors, biricodar (VX-710) and timcodar (VX-853), were evaluated for activity in a variety of bacteria. Both VX-710 and VX-853 potentiated the activity of ethidium bromide (EtBr), a model efflux substrate, against three clinically significant gram-positive pathogens: Staphylococcus aureus, Enterococcus faecalis, and Streptococcus pneumoniae. Similar to reserpine, VX-710 and VX-853 directly blocked EtBr efflux in S. aureus. Furthermore, these compounds were effective in lowering the MICs of several clinically used antibiotics, including fluoroquinolones, suggesting that VX-710 and VX-853 are representatives of a new class of bacterial efflux inhibitors with the potential for use in combination therapy.

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Antibacterial effect of S-Porphin sodium photodynamic therapy on Staphylococcus aureus and multiple drug resistance Staphylococcus aureus

Photodiagnosis and Photodynamic Therapy ◽

10.1016/j.pdpdt.2019.08.031 ◽

2019 ◽

Vol 28 ◽

pp. 80-87 ◽

Cited By ~ 4

Author(s):

Mengqi Jia ◽

Bingjie Mai ◽

Shupei Liu ◽

Zhaozhao Li ◽

Quanhong Liu ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Drug Resistance ◽

Photodynamic Therapy ◽

Antibacterial Effect ◽

Multiple Drug Resistance ◽

Multiple Drug

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Tissue Distribution and Chemical Induction of Multiple Drug Resistance Genes in Rats

Drug Metabolism and Disposition ◽

10.1124/dmd.30.7.838 ◽

2002 ◽

Vol 30 (7) ◽

pp. 838-844 ◽

Cited By ~ 110

Author(s):

James M. Brady ◽

Nathan J. Cherrington ◽

Dylan P. Hartley ◽

Susan C. Buist ◽

Ning Li ◽

...

Keyword(s):

Drug Resistance ◽

Tissue Distribution ◽

Resistance Genes ◽

Multiple Drug Resistance ◽

Multiple Drug ◽

Chemical Induction

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Mechanisms of bacterial multiresistance to antibiotics

Ecological genetics ◽

10.17816/ecogen1634-17 ◽

2018 ◽

Vol 16 (3) ◽

pp. 4-17 ◽

Cited By ~ 4

Author(s):

Olga M. Zemlyanko ◽

Tatyana M. Rogoza ◽

Galina A. Zhouravleva

Keyword(s):

Drug Resistance ◽

Clinical Practice ◽

Resistance Genes ◽

Horizontal Transfer ◽

Pathogenic Bacteria ◽

Multiple Drug Resistance ◽

Multiple Drug ◽

Bacterial Strains ◽

Current Review

Multiple drug resistance (MDR) to widening range of antibiotics emerging in increasing variety of pathogenic bacteria is a serious threat to the health of mankind nowadays. This is partially due to an uncontrolled usage of antibiotics not only in clinical practice, but also in various branches of agriculture. MDR is affected by two mechanisms: (1) accumulation of resistance genes as a result of intensive selection caused by antibiotics, and (2) active horizontal transfer of resistance genes. To unveil the reasons of bacterial multiresistance to antibiotics, it is necessary to understand the mechanisms of antibiotics action as well as the ways how either resistance to certain antibiotics emerge or resistance genes accumulate and transfer among bacterial strains. Current review is devoted to all these problems.

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Advanced molecular characterization of enteropathogenic Escherichia coli isolated from diarrheic camel neonates in Egypt

Veterinary World ◽

10.14202/vetworld.2021.85-91 ◽

2021 ◽

Vol 14 (1) ◽

pp. 85-91

Author(s):

Momtaz A. Shahein ◽

Amany N. Dapgh ◽

Essam Kamel ◽

Samah F. Ali ◽

Eman A. Khairy ◽

...

Keyword(s):

Escherichia Coli ◽

Drug Resistance ◽

Antibiotic Resistance ◽

Resistance Genes ◽

Multiple Drug Resistance ◽

Microbial Pathogens ◽

Multiple Drug ◽

Gastrointestinal Infections ◽

Fecal Samples ◽

E Coli

Background and Aim: Camels are important livestock in Egypt on cultural and economic bases, but studies of etiological agents of camelid diseases are limited. The enteropathogen Escherichia coli is a cause of broad spectrum gastrointestinal infections among humans and animals, especially in developing countries. Severe infections can lead to death. The current study aimed to identify pathogenic E. coli strains that cause diarrhea in camel calves and characterize their virulence and drug resistance at a molecular level. Materials and Methods: Seventy fecal samples were collected from diarrheic neonatal camel calves in Giza Governorate during 2018-2019. Samples were cultured on a selective medium for E. coli, and positive colonies were confirmed biochemically, serotyped, and tested for antibiotic susceptibility. E. coli isolates were further confirmed through detection of the housekeeping gene, yaiO, and examined for the presence of virulence genes; traT and fimH and for genes responsible for antibiotic resistance, ampC, aadB, and mphA. The isolates in the important isolated serotype, E. coli O26, were examined for toxigenic genes and sequenced. Results: The bacteriological and biochemical examination identified 12 E. coli isolates from 70 fecal samples (17.1%). Serotyping of these isolates showed four types: O26, four isolates, 33.3%; O103, O111, three isolates each, 25%; and O45, two isolates, 16.7%. The isolates showed resistance to vancomycin (75%) and ampicillin (66.6%), but were highly susceptible to ciprofloxacin, norfloxacin, and tetracycline (100%). The structural gene, yaiO (115 bp), was amplified from all 12 E. coli isolates and traT and fimH genes were amplified from 10 and 8 isolates, respectively. Antibiotic resistance genes, ampC, mphA, and aadB, were harbored in 9 (75%), 8 (66.6%), and 5 (41.7%), respectively. Seven isolates (58.3%) were MDR. Real-time-polymerase chain reaction of the O26 isolates identified one isolate harboring vt1, two with vt2, and one isolate with neither gene. Sequencing of the isolates revealed similarities to E. coli O157 strains. Conclusion: Camels and other livestock suffer various diseases, including diarrhea often caused by microbial pathogens. Enteropathogenic E. coli serotypes were isolated from diarrheic neonatal camel calves. These isolates exhibited virulence and multiple drug resistance genes.

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Ciclopirox Olamine Treatment Affects the Expression Pattern of Candida albicans Genes Encoding Virulence Factors, Iron Metabolism Proteins, and Drug Resistance Factors

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.47.6.1805-1817.2003 ◽

2003 ◽

Vol 47 (6) ◽

pp. 1805-1817 ◽

Cited By ~ 73

Author(s):

Markus Niewerth ◽

Donika Kunze ◽

Michael Seibold ◽

Martin Schaller ◽

Hans Christian Korting ◽

...

Keyword(s):

Drug Resistance ◽

Candida Albicans ◽

Resistance Genes ◽

Mode Of Action ◽

Multiple Drug Resistance ◽

Expression Patterns ◽

Multiple Drug ◽

Ciclopirox Olamine ◽

Genes Encoding ◽

In Cells

ABSTRACT The hydroxypyridone ciclopirox olamine belongs to the antimycotic drugs used for the treatment of superficial mycoses. In contrast to the azoles and other antimycotic drugs, its specific mode of action is only poorly understood. To investigate the mode of action of ciclopirox olamine on fungal viability, pathogenicity, and drug resistance, we examined the expression patterns of 47 Candida albicans genes in cells grown in the presence of a subinhibitory concentration (0.6 μg/ml) of ciclopirox olamine by reverse transcription-PCR. In addition, we used suppression-subtractive hybridization to further identify genes that are up-regulated in the presence of ciclopirox olamine. The expression of essential genes such as ACT1 was not significantly modified in cells exposed to ciclopirox olamine. Most putative and known virulence genes such as genes encoding secreted proteinases or lipases had no or only moderately reduced expression levels. In contrast, exposure of cells to ciclopirox olamine led to a distinct up- or down-regulation of genes encoding iron permeases or transporters (FTR1, FTR2, FTH1), a copper permease (CCC2), an iron reductase (CFL1), and a siderophore transporter (SIT1); these effects resembled those found under iron-limited conditions. Addition of FeCl3 to ciclopirox olamine-treated cells reversed the effect of the drug. Addition of the iron chelator bipyridine to the growth medium induced similar patterns of expression of distinct iron-regulated genes (FTR1, FTR2). While serum-induced yeast-to-hyphal phase transition of C. albicans was not affected in ciclopirox olamine-treated cells in the presence of subinhibitory conditions, a dramatic increase in sensitivity to oxidative stress was noted, which may indicate the reduced activities of iron-containing gene products responsible for detoxification. Although the Candida drug resistance genes CDR1 and CDR2 were up-regulated, no change in resistance or increased tolerance could be observed even after an incubation period of 6 months. This was in contrast to control experiments with fluconazole, in which the MICs for cells incubated with this drug had noticeably increased after 2 months. These data support the view that the antifungal activity of ciclopirox olamine may at least be partially caused by iron limitation. Furthermore, neither the expression of certain multiple-drug resistance genes nor other resistance mechanisms caused C. albicans resistance to this drug even after long-term exposure.

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