scholarly journals Serine Proteases Profiles of Leishmania (Viannia) Braziliensis Clinical Isolates With Distinct Susceptibilities to Antimony

2021 ◽  
Author(s):  
Anabel Zabala-Peñafiel ◽  
Geovane Dias-Lopes ◽  
Léa Cysne-Finkelstein ◽  
Fátima Conceição-Silva ◽  
Luciana de Freitas Campos Miranda ◽  
...  
Keyword(s):  
Serine Proteases ◽  
Principal Component ◽  
Clinical Isolates ◽  
First Line ◽  
Axenic Amastigotes ◽  
Homogeneous Cluster ◽  
Significant Difference ◽  
Tryparedoxin Peroxidase

Abstract Glucantime® (SbV) is the first-line treatment against leishmaniasis in South America. Its effectiveness has been associated with modulation of the parasite detoxification system that, in turn, is related to serine proteases such as subtilisins. In this study, 12 Leishmania (Viannia) braziliensis isolates from patients that presented clinical cure (Responders - R) and relapse or therapeutic failure (Non-responders - NR) were used. The parasites were assessed by in vitro susceptibility to SbIII and SbV, serine proteases activity – measured with z-FR-AMC as substrate and specific inhibitors – and expression of subtilisins and tryparedoxin-peroxidase (TXNPx). In vitro susceptibility of axenic amastigotes to SbIII showed a significant difference between R and NR groups. TLCK inhibited almost 100 % of activity in both axenic amastigotes and promastigotes while AEBSF inhibited around 70 %, and PMSF showed lower inhibition of specific isolates. Principal component and clustering analysis yielded one homogeneous cluster with only NR isolates and three heterogeneous clusters with R and NR isolates. Additionally, transcripts of subtilisins (LbrM.13.0860 and LbrM.28.2570) and TXNPx (LbrM.15.1080) were detected in promastigotes and axenic amastigotes from both groups. The data presented here show a phenotypic heterogeneity among the parasites, suggesting that exploration of in vitro phenotypes based on SbIII and serine proteases profiles can aid in the characterization of L. (V.) braziliensis clinical isolates.

scholarly journals Serine proteases profiles of Leishmania (Viannia) braziliensis clinical isolates with distinct susceptibilities to antimony

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anabel Zabala-Peñafiel ◽  
Geovane Dias-Lopes ◽  
Léa Cysne-Finkelstein ◽  
Fátima Conceição-Silva ◽  
Luciana de Freitas Campos Miranda ◽  
...  
Keyword(s):  
Serine Proteases ◽  
Principal Component ◽  
Clinical Isolates ◽  
In Vitro Susceptibility ◽  
Axenic Amastigotes ◽  
Homogeneous Cluster ◽  
Significant Difference ◽  
American Tegumentary Leishmaniasis

AbstractGlucantime (SbV) is the first-line treatment against American Tegumentary Leishmaniasis. Resistance cases to this drug have been reported and related to host characteristics and parasite phenotypes. In this study, 12 Leishmania (Viannia) braziliensis isolates from patients that presented clinical cure (Responders—R) and relapse or therapeutic failure (Non-responders—NR) after treatment with antimony, were analyzed. These parasites were assessed by in vitro susceptibility to SbIII and SbV, serine proteases activity measured with substrate (z-FR-AMC) and specific inhibitors (TLCK, AEBSF and PMSF). In vitro susceptibility of axenic amastigotes to SbIII showed a significant difference between R and NR groups. The protease assays showed that TLCK inhibited almost 100% of activity in both axenic amastigotes and promastigotes while AEBSF inhibited around 70%, and PMSF showed lower inhibition of some isolates. Principal component and clustering analysis performed with these data yielded one homogeneous cluster with only NR isolates and three heterogeneous clusters with R and NR isolates. Additionally, differential expression of subtilisins (LbrM.13.0860 and LbrM.28.2570) and TXNPx (LbrM.15.1080) was evaluated in promastigotes and axenic amastigotes from both groups. The results showed a higher expression of LbrM.13.0860 and LbrM.15.1080 genes in axenic amastigotes, while LbrM.28.2570 gene had the lowest expression in all isolates, regardless of the parasite form. The data presented here show a phenotypic heterogeneity among the parasites, suggesting that exploration of in vitro phenotypes based on SbIII and serine proteases profiles can aid in the characterization of L. (V.) braziliensis clinical isolates.

scholarly journals Serine Proteases Profiles of Leishmania (Viannia) Braziliensis Clinical Isolates With Distinct Susceptibilities to Antimony

2020 ◽  
Author(s):  
Anabel Zabala-Peñafiel ◽  
Geovane Dias-Lopes ◽  
Léa Cysne-Finkelstein ◽  
Fátima Conceição-Silva ◽  
Luciana de Freitas Campos Miranda ◽  
...  
Keyword(s):  
Serine Proteases ◽  
Principal Component ◽  
Clinical Isolates ◽  
Clinical Group ◽  
Axenic Amastigotes ◽  
Homogeneous Cluster ◽  
American Tegumentary Leishmaniasis ◽  
Serine Protease Activity ◽  
Gene Transcripts

Abstract Background: Glucantime® (SbV) is considered the first-line treatment against American Tegumentary Leishmaniasis in South America, though increased parasite resistance towards it have been reported and hampered its effectiveness. In this context, subtilisins serine proteases have been related to parasites’ susceptibility to drugs such as SbV and derivatives, through modulation of the parasite detoxification system. However, little is known about parasites causing ATL and their distinct responses towards this treatment.Methods: The study was conducted using Leishmania (Viannia) braziliensis clinical isolates from patients that presented clinical cure or Responders (R) and relapse/therapeutic failure or Non-responders (NR). Twelve clinical isolates were used to assess their in vitro susceptibility to SbIII and SbV, serine proteases activity, and expression of subtilisins-like and tryparedoxin-peroxidase (TXNPx) transcripts. Results: SbIII was able to better distinguish axenic amastigotes from each clinical group. These isolates were also assessed for serine protease activity, using z-FR-AMC as substrate and detecting distinct enzyme profiles with specific inhibitors. TLCK inhibited almost 100% of activity in both promastigotes and axenic amastigotes while AEBSF inhibited around 70%. PMSF showed low inhibition of specific isolates (35%). Gathering all the quantitative data, we performed principal component analysis and then used the K-means algorithm to cluster the isolates. This analysis yielded one cluster with only one isolate (R isolate), one homogeneous cluster (NR isolates), and three heterogeneous clusters (R and NR isolates). Additionally, gene transcripts of subtilisins and TXNPx were detected in promastigotes and axenic amastigotes from both groups. Conclusions: Cluster analysis showed that there is a phenotypic heterogeneity among the isolates, however, exploration of in vitro phenotypes based on SbIII and serine proteases profiles can aid in the characterization and better understanding of L. (V.) braziliensis clinical isolates.

scholarly journals Comparative In Vitro Activities of Torezolid (DA-7157) against Clinical Isolates of Aerobic and Anaerobic Bacteria in South Korea

2010 ◽  
Vol 54 (12) ◽  
pp. 5381-5386 ◽  
Author(s):  
Jong Hwa Yum ◽  
Sung Hak Choi ◽  
Dongeun Yong ◽  
Yunsop Chong ◽  
Weon Bin Im ◽  
...  
Keyword(s):  
South Korea ◽  
Antimicrobial Agents ◽  
Anaerobic Bacteria ◽  
Clinical Isolates ◽  
Bacterial Isolates ◽  
First Line ◽  
Gram Positive ◽  
The World ◽  
Aerobic And Anaerobic

ABSTRACT Resistance of Gram-positive pathogens to first-line antimicrobial agents has been increasing in many parts of the world. We compared the in vitro activities of torezolid with those of other antimicrobial agents, including linezolid, against clinical isolates of major aerobic and anaerobic bacteria. Torezolid had an MIC90 of ≤0.5 μg/ml for the Gram-positive bacterial isolates tested and was more potent than either linezolid or vancomycin.

scholarly journals Characterization of Spontaneous, In Vitro-Selected, Rifampin-Resistant Mutants of Mycobacterium tuberculosisStrain H37Rv

2000 ◽  
Vol 44 (12) ◽  
pp. 3298-3301 ◽  
Author(s):  
Glenn P. Morlock ◽  
Bonnie B. Plikaytis ◽  
Jack T. Crawford
Keyword(s):  
Point Mutations ◽  
Laboratory Strain ◽  
Resistant Mutant ◽  
Small Region ◽  
Clinical Isolates ◽  
Gene Coding ◽  
Resistant Mutants ◽  
Strain H37rv

ABSTRACT Resistance to rifampin in Mycobacterium tuberculosisresults from mutations in the gene coding for the beta subunit of RNA polymerase (rpoB). At least 95% of rifampin-resistant isolates have mutations in rpoB, and the mutations are clustered in a small region. About 40 distinct point mutations and in-frame insertions and deletions in rpoB have been identified, but point mutations in two codons, those coding for Ser531 and His526, are seen in about 70% of rifampin-resistant clinical isolates, with Ser531-to-Leu (TCG-to-TGG) mutations being by far the most common. To explore this phenomenon, we isolated independent, spontaneous, rifampin-resistant mutant versions of well-characterized M. tuberculosislaboratory strain H37Rv by plating 100 separate cultures, derived from a single low-density inoculum, onto rifampin-containing medium. Rifampin-resistant mutants were obtained from 64 of these cultures. Although we anticipated that the various point mutations would occur with approximately equal frequencies, sequencing the rpoBgene from one colony per plate revealed that 39 (60.9%) were Ser531 to Leu. We conclude that, for unknown reasons, the associated rpoB mutation occurs at a substantially higher rate than other rpoB mutations. This higher mutation rate may contribute to the high percentage of this mutation seen in clinical isolates.

scholarly journals Synergy of gatifloxacin with cefoperazone and cefoperazone–sulbactam against resistant strains of Pseudomonas aeruginosa

2008 ◽  
Vol 57 (12) ◽  
pp. 1514-1517 ◽  
Author(s):  
N. Sivagurunathan ◽  
S. Krishnan ◽  
J. Venkat Rao ◽  
Anantha Naik Nagappa ◽  
V. M. Subrahmanyam ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Clinical Isolates ◽  
Significant Difference ◽  
Resistant Strains ◽  
Time Kill

Chequerboard and time–kill methods were used to compare the in vitro efficacies of the combinations gatifloxacin (GAT) with cefoperazone (CFP) and GAT with cefoperazone–sulbactam (CFP-SUL) against 58 clinical isolates of Pseudomonas aeruginosa. The combinations GAT+CFP and GAT+CFP-SUL were shown to be synergistic for 36.2 and 58.6 % of isolates tested, respectively, using the chequerboard method. Time–kill studies with 11 strains showed synergy in 54.5 % for the GAT+CFP combination and 72.7 % for the GAT+CFP-SUL combination. The agreement between these two methods was found to be 72–81 %. There was a significant difference in synergy between the two combinations tested (P=0.011).

scholarly journals Proteomic and Metabolomic Characterization of Metabolically Healthy Obesity: A Descriptive Study from a Swedish Cohort

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
J. Korduner ◽  
P. M. Nilsson ◽  
O. Melander ◽  
M. J. Gerl ◽  
G. Engström ◽  
...  
Keyword(s):  
Interleukin 1 ◽  
Principal Component ◽  
Metabolically Healthy Obesity ◽  
Established Risk Factor ◽  
The Metabolic Syndrome ◽  
Significant Difference ◽  
Metabolite Profiles ◽  
History Of ◽  
Metabolically Healthy

Background/Aims. Obesity is a well-established risk factor for the development of numerous chronic diseases. However, there is a small proportion of obese individuals that seem to escape these aforementioned conditions—Metabolically Healthy Obesity (MHO). Our aim was to do a metabolic and biomarker profiling of MHO individuals. Method. Associations between different biomarkers (proteomics, lipidomics, and metabolomics) coupled to either MHO or metabolically unhealthy obese (MUO) individuals were analyzed through principal component analysis (PCA). Subjects were identified from a subsample of 416 obese individuals, selected from the Malmö Diet and Cancer study—Cardiovascular arm (MDCS-CV, n = 3,443). They were further divided into MHO (n = 143) and MUO (n = 273) defined by a history of hospitalization, or not, at baseline inclusion, and nonobese subjects (NOC, n = 3,027). Two distinctive principle components (PL2, PP5) were discovered with a significant difference and thus further investigated through their main loadings. Results. MHO individuals had a more metabolically favorable lipid and glucose profile than MUO subjects, that is, lower levels of traditional blood glucose and triglycerides, as well as a trend of lower metabolically unfavorable lipid biomarkers. PL2 (lipidomics, p = 0.02 ) showed stronger associations of triacylglycerides with MUO, whereas phospholipids correlated with MHO. PP5 (proteomics, p = 0.01 ) included interleukin-1 receptor antagonist (IL-1ra) and leptin with positive relations to MUO and galanin that correlated positively to MHO. The group differences in metabolite profiles were to a large extent explained by factors included in the metabolic syndrome. Conclusion. Compared to MUO individuals, corresponding MHO individuals present with a more favorable lipid metabolic profile, accompanied by a downregulation of potentially harmful proteomic biomarkers. This unique and extensive biomarker profiling presents novel data on potentially differentiating traits between these two obese phenotypes.

scholarly journals Heterogeneity among Isolates Reveals that Fitness in Low Oxygen Correlates withAspergillus fumigatusVirulence

mBio ◽  
2016 ◽  
Vol 7 (5) ◽  
Author(s):  
Caitlin H. Kowalski ◽  
Sarah R. Beattie ◽  
Kevin K. Fuller ◽  
Elizabeth A. McGurk ◽  
Yi-Wei Tang ◽  
...  
Keyword(s):  
Aspergillus Fumigatus ◽  
Experimental Evolution ◽  
Invasive Pulmonary Aspergillosis ◽  
Clinical Isolates ◽  
Low Oxygen ◽  
Single Strain ◽  
Hypoxia Exposure ◽  
Significant Difference

ABSTRACTPrevious work has shown that environmental and clinical isolates ofAspergillus fumigatusrepresent a diverse population that occupies a variety of niches, has extensive genetic diversity, and exhibits virulence heterogeneity in a number of animal models of invasive pulmonary aspergillosis (IPA). However, mechanisms explaining differences in virulence amongA. fumigatusisolates remain enigmatic. Here, we report a significant difference in virulence of two common lab strains, CEA10 and AF293, in the murine triamcinolone immunosuppression model of IPA, in which we previously identified severe low oxygen microenvironments surrounding fungal lesions. Therefore, we hypothesize that the ability to thrive within these lesions of low oxygen promotes virulence ofA. fumigatusin this model. To test this hypothesis, we performedin vitrofitness andin vivovirulence analyses in the triamcinolone murine model of IPA with 14 environmental and clinical isolates ofA. fumigatus. Among these isolates, we observed a strong correlation between fitness in low oxygenin vitroand virulence. In further support of our hypothesis, experimental evolution of AF293, a strain that exhibits reduced fitness in low oxygen and reduced virulence in the triamcinolone model of IPA, results in a strain (EVOL20) that has increased hypoxia fitness and a corresponding increase in virulence. Thus, the ability to thrive in low oxygen correlates with virulence ofA. fumigatusisolates in the context of steroid-mediated murine immunosuppression.IMPORTANCEAspergillus fumigatusoccupies multiple environmental niches, likely contributing to the genotypic and phenotypic heterogeneity among isolates. Despite reports of virulence heterogeneity, pathogenesis studies often utilize a single strain for the identification and characterization of virulence and immunity factors. Here, we describe significant variation betweenA. fumigatusisolates in hypoxia fitness and virulence, highlighting the advantage of including multiple strains in future studies. We also illustrate that hypoxia fitness correlates strongly with increased virulence exclusively in the nonleukopenic murine triamcinolone immunosuppression model of IPA. Through an experimental evolution experiment, we observe that chronic hypoxia exposure results in increased virulence ofA. fumigatus. We describe here the first observation of a model-specific virulence phenotype correlative within vitrofitness in hypoxia and pave the way for identification of hypoxia-mediated mechanisms of virulence in the fungal pathogenA. fumigatus.

scholarly journals Species-dependent variation of the gut bacterial communities across Trypanosoma cruzi insect vectors

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0240916
Author(s):  
Luisa M. Arias-Giraldo ◽  
Marina Muñoz ◽  
Carolina Hernández ◽  
Giovanny Herrera ◽  
Natalia Velásquez-Ortiz ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Bacterial Communities ◽  
Principal Component ◽  
Rrna Gene ◽  
Insect Vectors ◽  
Infection Frequency ◽  
Alpha And Beta Diversity ◽  
Bacterial Phyla ◽  
Significant Difference

Triatomines (Hemiptera: Reduviidae) are the insect vectors of Trypanosoma cruzi, the causative agent of Chagas disease. The gut bacterial communities affect the development of T. cruzi inside the vector, making the characterization of its composition important in the understanding of infection development. We collected 54 triatomine bugs corresponding to four genera in different departments of Colombia. DNA extraction and PCR were performed to evaluate T. cruzi presence and to determine the discrete typing unit (DTU) of the parasite. PCR products of the bacterial 16S rRNA gene were pooled and sequenced. Resulting reads were denoised and QIIME 2 was used for the identification of amplicon sequence variants (ASVs). Diversity (alpha and beta diversity) and richness analyses, Circos plots, and principal component analysis (PCA) were also performed. The overall T. cruzi infection frequency was 75.9%, with TcI being the predominant DTU. Approximately 500,000 sequences were analyzed and 27 bacterial phyla were identified. The most abundant phyla were Proteobacteria (33.9%), Actinobacteria (32.4%), Firmicutes (19.6%), and Bacteroidetes (7.6%), which together accounted for over 90% of the gut communities identified in this study. Genera were identified for these main bacterial phyla, revealing the presence of important bacteria such as Rhodococcus, Serratia, and Wolbachia. The composition of bacterial phyla in the gut of the insects was significantly different between triatomine species, whereas no significant difference was seen between the state of T. cruzi infection. We suggest further investigation with the evaluation of additional variables and a larger sample size. To our knowledge, this study is the first characterization of the gut bacterial structure of the main triatomine genera in Colombia.

scholarly journals Transcriptional Profile and Structural Conservation of SUMO-Specific Proteases inSchistosoma mansoni

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Roberta Verciano Pereira ◽  
Fernanda Janku Cabral ◽  
Matheus de Souza Gomes ◽  
Liana Konovaloff Jannotti-Passos ◽  
William Castro-Borges ◽  
...  
Keyword(s):  
Protein Localization ◽  
Cell Cycle Control ◽  
Developmentally Regulated ◽  
Cellular Processes ◽  
Significant Difference ◽  
Endopeptidase Activity ◽  
Regulated Expression ◽  
Differential Gene

Small ubiquitin-related modifier (SUMO) is involved in numerous cellular processes including protein localization, transcription, and cell cycle control. SUMOylation is a dynamic process, catalyzed by three SUMO-specific enzymes and reversed by Sentrin/SUMO-specific proteases (SENPs). Here we report the characterization of these proteases inSchistosoma mansoni. Usingin silicoanalysis, we identified two SENPs sequences, orthologs of mammalian SENP1 and SENP7, confirming their identities and conservation through phylogenetic analysis. In addition, the transcript levels ofSmsenp1/7in cercariae, adult worms, andin vitrocultivated schistosomula were measured by qRT-PCR. Our data revealed upregulation of theSmsenp1/7transcripts in cercariae and early schistosomula, followed by a marked differential gene expression in the other analyzed stages. However, no significant difference in expression profile between the paralogs was observed for the analyzed stages. Furthermore, in order to detect deSUMOylating capabilities in crude parasite extracts,SmSENP1 enzymatic activity was evaluated using SUMO-1-AMC substrate. The endopeptidase activity related to SUMO-1 precursor processing did not differ significantly between cercariae and adult worms. Taken together, these results support the developmentally regulated expression of SUMO-specific proteases inS. mansoni.

scholarly journals In Vitro Antifungal Susceptibility and Molecular Characterization of Clinical Isolates of Fusarium verticillioides (F. moniliforme) and Fusarium thapsinum

2008 ◽  
Vol 52 (6) ◽  
pp. 2228-2231 ◽  
Author(s):  
Mónica Azor ◽  
Josepa Gené ◽  
Josep Cano ◽  
Deanna A. Sutton ◽  
Annette W. Fothergill ◽  
...  
Keyword(s):  
Active Drug ◽  
Fusarium Verticillioides ◽  
Antifungal Susceptibility ◽  
Antifungal Drugs ◽  
Clinical Isolates ◽  
Microdilution Method ◽  
Fusarium Thapsinum ◽  
In Vitro Antifungal Susceptibility

ABSTRACT A microdilution method was used to test 11 antifungal drugs against clinical isolates of Fusarium thapsinum and three different phylogenetic clades of Fusarium verticillioides that were characterized by sequencing a region of the β-tubulin gene. Terbinafine was the most-active drug against both species, followed by posaconazole against F. verticillioides.

Sign in / Sign up

Export Citation Format

Share Document