scholarly journals HPLC-MS identification and expression of Candida drug-resistance proteins from African HIV-infected patients

2021 ◽  
Vol 7 (3) ◽  
pp. 320-335
Author(s):  
Pedro M D S Abrantes ◽  
◽  
Randall Fisher ◽  
Patrick J D Bouic ◽  
Carole P McArthur ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Efflux Pump ◽  
Ergosterol Biosynthesis ◽  
Hiv Positive ◽  
Multidrug Transporter ◽  
Resistance Proteins ◽  
African Patients ◽  
Shock Proteins ◽  
Estrogen Binding ◽  
Isolated Species

<abstract> <p>The objective of this study was to elucidate the proteomic mechanisms of drug resistance in HIV-infected African patients. Cell membrane fractions from forty oral <italic>Candida</italic> isolates isolated from African HIV-positive patients were analysed using HPLC-MS with the aim of identifying proteins associated with their pathogenicity and drug resistance. Heat shock proteins that mediate the fungicidal activity of salivary peptides were found in all tested <italic>Candida</italic> fractions, with pH-responsive proteins associated with increased pathogenicity only being present in the three most commonly isolated species. ABC multidrug transporter efflux pumps and estrogen binding proteins were only found in <italic>C. albicans</italic> fractions, while ergosterol biosynthesis proteins were identified in four species. The combination of various adherence, invasion, upregulation and efflux pump mechanisms appear to be instrumental for the <italic>Candida</italic> host colonization and drug resistance emergence in HIV-infected individuals.</p> </abstract>

scholarly journals Set1-mediated histone H3K4 methylation is required for azole induction of the ergosterol biosynthesis genes and antifungal drug resistance in Candida glabrata.

2021 ◽  
Author(s):  
Kortany M Baker ◽  
Smriti Hoda ◽  
Debasmita Saha ◽  
Livia Georgescu ◽  
Nina D Serratore ◽  
...  
Keyword(s):  
Gene Expression ◽  
Drug Resistance ◽  
Candida Glabrata ◽  
Efflux Pump ◽  
Opportunistic Pathogen ◽  
Ergosterol Biosynthesis ◽  
H3k4 Methylation ◽  
Antifungal Drug Resistance ◽  
H3k4 Trimethylation ◽  
Histone H3k4

Candida glabrata is an opportunistic pathogen that has developed the ability to adapt and thrive under azole treated conditions. The common mechanisms that can result in Candida drug resistance are due to mutations or overexpression of the drug efflux pump or the target of azole drugs, Cdr1 and Erg11, respectively. However, the role of epigenetic histone modifications in azole-induced gene expression and drug resistance are poorly understood in C. glabrata. In this study, we show for the first time that Set1 mediates histone H3K4 mono-, di-, and trimethylation in C. glabrata. In addition, loss of SET1 and histone H3K4 methylation results in increased susceptibility to azole drugs in both C. glabrata and S. cerevisiae. Intriguingly, this increase in susceptibility to azole drugs in strains lacking Set1-mediated histone H3K4 methylation is not due to altered transcript levels of CDR1, PDR1 or Cdr1s ability to efflux drugs. Genome-wide transcript analysis revealed that Set1 is necessary for azole-induced expression of 12 genes involved in the late biosynthesis of ergosterol including ERG11 and ERG3. Importantly, chromatin immunoprecipitation analysis showed that histone H3K4 trimethylation was detected on chromatin of actively transcribed ERG genes. Furthermore, H3K4 trimethylation increased upon azole-induced gene expression which was also found to be dependent on the catalytic activity of Set1. Altogether, our findings show that Set1-mediated histone H3K4 methylation governs the intrinsic drug resistant status in C. glabrata via epigenetic control of azole-induced ERG gene expression.

scholarly journals Genomewide Location Analysis of Candida albicans Upc2p, a Regulator of Sterol Metabolism and Azole Drug Resistance

2008 ◽  
Vol 7 (5) ◽  
pp. 836-847 ◽  
Author(s):  
Sadri Znaidi ◽  
Sandra Weber ◽  
Osman Zin Al-Abdin ◽  
Perrine Bomme ◽  
Saloua Saidane ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Candida Albicans ◽  
Efflux Pump ◽  
Ergosterol Biosynthesis ◽  
Zinc Cluster ◽  
Dna Motif ◽  
C Terminus ◽  
Genes Encoding ◽  
Important Regulator

ABSTRACT Upc2p, a transcription factor of the zinc cluster family, is an important regulator of sterol biosynthesis and azole drug resistance in Candida albicans. To better understand Upc2p function in C. albicans, we used genomewide location profiling to identify the transcriptional targets of Upc2p in vivo. A triple hemagglutinin epitope, introduced at the C terminus of Upc2p, conferred a gain-of-function effect on the fusion protein. Location profiling identified 202 bound promoters (P < 0.05). Overrepresented functional groups of genes whose promoters were bound by Upc2p included 12 genes involved in ergosterol biosynthesis (NCP1, ERG11, ERG2, and others), 18 genes encoding ribosomal subunits (RPS30, RPL32, RPL12, and others), 3 genes encoding drug transporters (CDR1, MDR1, and YOR1), 4 genes encoding transcription factors (INO2, ACE2, SUT1, and UPC2), and 6 genes involved in sulfur amino acid metabolism (MET6, SAM2, SAH1, and others). Bioinformatic analyses suggested that Upc2p binds to the DNA motif 5′-VNCGBDTR that includes the previously characterized Upc2p binding site 5′-TCGTATA. Northern blot analysis showed that increased binding correlates with increased expression for the analyzed Upc2p targets (ERG11, MDR1, CDR1, YOR1, SUT1, SMF12, and CBP1). The analysis of ERG11, MDR1, and CDR1 transcripts in wild-type and upc2Δ/upc2Δ strains grown under Upc2p-activating conditions (lovastatin treatment and hypoxia) showed that Upc2p regulates its targets in a complex manner, acting as an activator or as a repressor depending upon the target and the activating condition. Taken together, our results indicate that Upc2p is a key regulator of ergosterol metabolism. They also suggest that Upc2p may contribute to azole resistance by regulating the expression of drug efflux pump-encoding genes in addition to ergosterol biosynthesis genes.

scholarly journals Camphor and Eucalyptol—Anticandidal Spectrum, Antivirulence Effect, Efflux Pumps Interference and Cytotoxicity

2021 ◽  
Vol 22 (2) ◽  
pp. 483
Author(s):  
Marija Ivanov ◽  
Abhilash Kannan ◽  
Dejan S. Stojković ◽  
Jasmina Glamočlija ◽  
Ricardo C. Calhelha ◽  
...  
Keyword(s):  
Fungal Pathogens ◽  
Efflux Pump ◽  
Efflux Pumps ◽  
Liver Cells ◽  
Ergosterol Biosynthesis ◽  
Antifungal Compound ◽  
Porcine Liver ◽  
Fungal Virulence ◽  
Genes Encoding ◽  
Plant Constituents

Candidaalbicans represents one of the most common fungal pathogens. Due to its increasing incidence and the poor efficacy of available antifungals, finding novel antifungal molecules is of great importance. Camphor and eucalyptol are bioactive terpenoid plant constituents and their antifungal properties have been explored previously. In this study, we examined their ability to inhibit the growth of different Candida species in suspension and biofilm, to block hyphal transition along with their impact on genes encoding for efflux pumps (CDR1 and CDR2), ergosterol biosynthesis (ERG11), and cytotoxicity to primary liver cells. Camphor showed excellent antifungal activity with a minimal inhibitory concentration of 0.125–0.35 mg/mL while eucalyptol was active in the range of 2–23 mg/mL. The results showed camphor’s potential to reduce fungal virulence traits, that is, biofilm establishment and hyphae formation. On the other hand, camphor and eucalyptol treatments upregulated CDR1;CDR2 was positively regulated after eucalyptol application while camphor downregulated it. Neither had an impact on ERG11 expression. The beneficial antifungal activities of camphor were achieved with an amount that was non-toxic to porcine liver cells, making it a promising antifungal compound for future development. The antifungal concentration of eucalyptol caused cytotoxic effects and increased expression of efflux pump genes, which suggests that it is an unsuitable antifungal candidate.

scholarly journals Transporters and Efflux Pumps Are the Main Mechanisms Involved in Staphylococcus epidermidis Adaptation and Tolerance to Didecyldimethylammonium Chloride

2020 ◽  
Vol 8 (3) ◽  
pp. 344 ◽  
Author(s):  
Urška Ribič ◽  
Jernej Jakše ◽  
Nataša Toplak ◽  
Simon Koren ◽  
Minka Kovač ◽  
...  
Keyword(s):  
Staphylococcus Epidermidis ◽  
Biofilm Formation ◽  
Efflux Pump ◽  
Thioredoxin Reductase ◽  
Multidrug Transporter ◽  
Acid Biosynthesis ◽  
Tolerance Mechanisms ◽  
Down Regulation ◽  
Didecyldimethylammonium Chloride ◽  
First Time

Staphylococcus epidermidis cleanroom strains are often exposed to sub-inhibitory concentrations of disinfectants, including didecyldimethylammonium chloride (DDAC). Consequently, they can adapt or even become tolerant to them. RNA-sequencing was used to investigate adaptation and tolerance mechanisms of S. epidermidis cleanroom strains (SE11, SE18), with S. epidermidis SE11Ad adapted and S. epidermidis SE18To tolerant to DDAC. Adaptation to DDAC was identified with up-regulation of genes mainly involved in transport (thioredoxin reductase [pstS], the arsenic efflux pump [gene ID, SE0334], sugar phosphate antiporter [uhpT]), while down-regulation was seen for the Agr system (agrA, arC, agrD, psm, SE1543), for enhanced biofilm formation. Tolerance to DDAC revealed the up-regulation of genes associated with transporters (L-cysteine transport [tcyB]; uracil permease [SE0875]; multidrug transporter [lmrP]; arsenic efflux pump [arsB]); the down-regulation of genes involved in amino-acid biosynthesis (lysine [dapE]; histidine [hisA]; methionine [metC]), and an enzyme involved in peptidoglycan, and therefore cell wall modifications (alanine racemase [SE1079]). We show for the first time the differentially expressed genes in DDAC-adapted and DDAC-tolerant S. epidermidis strains, which highlight the complexity of the responses through the involvement of different mechanisms.

scholarly journals CaNdt80 Is Involved in Drug Resistance in Candida albicans by Regulating CDR1

2004 ◽  
Vol 48 (12) ◽  
pp. 4505-4512 ◽  
Author(s):  
Chia-Geun Chen ◽  
Yun-Liang Yang ◽  
Hsin-I Shih ◽  
Chia-Li Su ◽  
Hsiu-Jung Lo
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Drug Resistance ◽  
Candida Albicans ◽  
Type Strain ◽  
Antifungal Agents ◽  
Wild Type Strain ◽  
Efflux Pump ◽  
Antifungal Drugs ◽  
Galactosidase Activity ◽  
Wild Type

ABSTRACT Overexpression of CDR1, an efflux pump, is one of the major mechanisms contributing to drug resistance in Candida albicans. CDR1 p-lacZ was constructed and transformed into a Saccharomyces cerevisiae strain so that the lacZ gene could be used as the reporter to monitor the activity of the CDR1 promoter. Overexpression of CaNDT80, the C. albicans homolog of S. cerevisiae NDT80, increases the β-galactosidase activity of the CDR1 p-lacZ construct in S. cerevisiae. Furthermore, mutations in CaNDT80 abolish the induction of CDR1 expression by antifungal agents in C. albicans. Consistently, the Candt80/Candt80 mutant is also more susceptible to antifungal drugs than the wild-type strain. Thus, the gene for CaNdt80 may be the first gene among the regulatory factors involved in drug resistance in C. albicans whose function has been identified.

Antimalarial drug resistance markers in human immunodeficiency virus (HIV)-positive and HIV-negative adults with asymptomatic malaria infections in Port Harcourt, Nigeria

2021 ◽  
Author(s):  
Ifeyinwa Chijioke-Nwauche ◽  
Mary C Oguike ◽  
Chijioke A Nwauche ◽  
Khalid B Beshir ◽  
Colin J Sutherland
Keyword(s):  
Human Immunodeficiency Virus ◽  
Drug Resistance ◽  
Drug Susceptibility ◽  
Blood Film ◽  
University Hospital ◽  
Hiv Positive ◽  
Asymptomatic Malaria ◽  
Immunodeficiency Virus ◽  
Before And After ◽  
Hiv Negative

Abstract Background In Nigeria, indiscriminate use of antimalarial drugs may contribute to the threat of drug resistance, but this has not been evaluated among people living with human immunodeficiency virus (HIV). Methods HIV-positive adults attending a university hospital HIV clinic and HIV-negative adult volunteers from the university hospital community with a positive blood film were treated with artemether–lumefantrine. Parasite DNA from before and after treatment was polymerase chain reaction amplified to identify molecular markers of drug susceptibility. Results The pfcrt76T genotype was prevalent among both HIV-positive and HIV-negative participants (78.6% and 68.2%, respectively). Three new mutations in the pfmdr1 gene—F73S, S97L and G165R—and the uncommon pfdhps S436F variant were detected, whereas pfdhps K540E and pfdhfr I164L were absent. The A437G allele of pfdhps predominated (62/66 [94%]). The I431 V mutation was found in 19 of 66 pretreatment pfdhps sequences (28.8%). The pfmdr1 86N allele was significantly more common at day 3 post-treatment than at baseline (odds ratio 8.77 [95% confidence interval 1.21 to 380]). Conclusions We found evidence of continued chloroquine use among HIV-positive individuals. Selection for the pfmdr1 86N after artemether–lumefantrine treatment was observed, indicating a possible threat to antimalarial efficacy in the study area. The complexity of pfdhps haplotypes emphasises the need for careful monitoring of anti-folate susceptibility in Nigeria.

Kinetics of the multidrug transporter (P-glycoprotein) and its reversal

1997 ◽  
Vol 77 (2) ◽  
pp. 545-590 ◽  
Author(s):  
W. D. Stein
Keyword(s):  
Final Section ◽  
Transport Kinetics ◽  
Multidrug Transporter ◽  
Chemotherapeutic Drugs ◽  
Multidrug Resistance Proteins ◽  
Binding Properties ◽  
Membrane Pump ◽  
Resistance Proteins ◽  
P Glycoprotein ◽  
Kinetics Of

Most cancer deaths result from the cancer's either being intrinsically resistant to chemotherapeutic drugs or becoming resistant after being initially sensitive. Often, in cells grown in cell culture, drug resistance correlates with the presence of one or more of the so-called P-glycoproteins or multidrug resistance proteins, products of the mdr family of genes. This review is largely concerned with the transport kinetics of the P-glycoproteins. We first present a brief overview of the P-glycoproteins, their properties, and their clinical significance. Later sections of the review expand on this material with special emphasis on the substrates of P-glycoprotein and how they cross the cell membrane, on the transport kinetics of the P-glycoprotein, on reversers of its action, and on its activity as an ATPase. In a final section, we consider the mechanism of action of P-glycoprotein as an actively transporting membrane pump. The characteristic of P-glycoprotein considered the most difficult to explain is its very broad specificity (or lack of specificity), but there are precedents for this property in well-known proteins such as serum albumin, which binds a range of molecular types, including substrates and reversers of P-glycoprotein, seemingly as broad as does P-glycoprotein. Pointing out this analogy does not provide a molecular explanation for the substrate-binding properties of P-glycoprotein but does make those properties more assimilable.

scholarly journals The Emerging Role of Extracellular Vesicle-Mediated Drug Resistance in Cancers: Implications in Advanced Prostate Cancer

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Carolina Soekmadji ◽  
Colleen C. Nelson
Keyword(s):  
Prostate Cancer ◽  
Drug Resistance ◽  
Multidrug Resistance ◽  
Advanced Prostate Cancer ◽  
Control Cell ◽  
Extracellular Vesicle ◽  
Multidrug Resistance Proteins ◽  
Acquired Drug Resistance ◽  
Resistance Proteins

Emerging evidence has shown that the extracellular vesicles (EVs) regulate various biological processes and can control cell proliferation and survival, as well as being involved in normal cell development and diseases such as cancers. In cancer treatment, development of acquired drug resistance phenotype is a serious issue. Recently it has been shown that the presence of multidrug resistance proteins such as Pgp-1 and enrichment of the lipid ceramide in EVs could have a role in mediating drug resistance. EVs could also mediate multidrug resistance through uptake of drugs in vesicles and thus limit the bioavailability of drugs to treat cancer cells. In this review, we discussed the emerging evidence of the role EVs play in mediating drug resistance in cancers and in particular the role of EVs mediating drug resistance in advanced prostate cancer. The role of EV-associated multidrug resistance proteins, miRNA, mRNA, and lipid as well as the potential interaction(s) among these factors was probed. Lastly, we provide an overview of the current available treatments for advanced prostate cancer, considering where EVs may mediate the development of resistance against these drugs.

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