Characterization of Trichophyton mentagrophytes multiple drug resistance genes

Abstract Background: The emergence of multi-drug resistant Citrobacter freundii poses daunting challenges to the treatment of clinical infections. The purpose of this study was to characterize the genome of a C. freundii strain with an IncX3 plasmid encoding both the blaNDM-1 and blaSHV-12 genes.Methods: Strain ZT01-0079 was isolated from a clinical urine sample. The Vitek2 system was used for identification and antimicrobial susceptibility testing. The presence of blaNDM-1 was detected by PCR and sequencing. Conjugation experiments and Southern blotting were performed to determine the transferability of the blaNDM-1- carrying plasmid. Nanopore and Illumina sequencing were performed to better understand the genomic characteristics of the strain.Results: Strain ZT01-0079 was identified as C. freundii, and the coexistence of blaNDM-1 and multiple drug resistance genes was confirmed. Electrophoresis and Southern blotting showed that blaNDM-1 was located on a ~53kb IncX3 plasmid. The NDM-1-encoding plasmid was successfully transferred at a frequency of 1.68×10−3. Both blaNDM-1 and blaSHV-12 were located on the self-transferable IncX3 plasmid.Conclusion: The rapid spread of the IncX3 plasmid highlights the importance of continuous monitoring of the prevalence of NDM-1-encoding Enterobacteriaceae. Mutations of existing carbapenem resistance genes will bring formidable challenges to clinical treatment.

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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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Ubiquitous Conjugative Mega-Plasmids of Acinetobacter Species and Their Role in Horizontal Transfer of Multi-Drug Resistance

Frontiers in Microbiology ◽

10.3389/fmicb.2021.728644 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sofia Mindlin ◽

Olga Maslova ◽

Alexey Beletsky ◽

Varvara Nurmukanova ◽

Zhiyong Zong ◽

...

Keyword(s):

Drug Resistance ◽

Multiple Drug Resistance ◽

Antibiotic Resistance Genes ◽

Multi Drug Resistance ◽

Clear Correlation ◽

Multiple Drug ◽

Special Role ◽

Acinetobacter Species ◽

Group Iii

Conjugative mega-plasmids play a special role in adaptation since they carry a huge number of accessory genes, often allowing the host to develop in new niches. In addition, due to conjugation they are able to effectively spread themselves and participate in the transfer of small mobilizable plasmids. In this work, we present a detailed characterization of a recently discovered family of multiple-drug resistance mega-plasmids of Acinetobacter species, termed group III-4a. We describe the structure of the plasmid backbone region, identify the rep gene and the origin of plasmid replication, and show that plasmids from this group are able not only to move between different Acinetobacter species but also to efficiently mobilize small plasmids containing different mob genes. Furthermore, we show that the population of natural Acinetobacter strains contains a significant number of mega-plasmids and reveal a clear correlation between the living conditions of Acinetobacter strains and the structure of their mega-plasmids. In particular, comparison of the plasmids from environmental and clinical strains shows that the genes for resistance to heavy metals were eliminated in the latter, with the simultaneous accumulation of antibiotic resistance genes by incorporation of transposons and integrons carrying these genes. The results demonstrate that this group of mega-plasmids plays a key role in the dissemination of multi-drug resistance among Acinetobacter species.

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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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