(FBIOyF) Departamento de Bioquímica Clínica - Artículos

URI permanente para esta colección

Examinar

Envíos recientes

Mostrando 1 - 20 de 46
  • ÍtemAcceso Abierto
    Acinetobacter baumannii response to cefiderocol challenge in human urine
    (Nature, 2022-05-24) Nishimura, Brent; Escalante, Jenny; Tuttobene, Marisel Romina; Subils, Tomás; Mezcord, Vyanka; Pimentel, Camila; Georgeos, Nardin; Pasteran, Fernando; Rodríguez, Cecilia; Sieira, Rodrigo; Actis, Luis A.; Tolmasky,, Marcelo E.; Bonomo, Robert A.; Ramírez, María Soledad
    Cefiderocol (CFDC) is a novel chlorocatechol-substituted siderophore antibiotic approved to treat complicated urinary tract infections (cUTI) and hospital-acquired and ventilator-acquired pneumonia (HAP/VAP). Previous work determined that albumin-rich human fluids increase the minimum inhibitory concentration (MICs) of Acinetobacter baumannii against CFDC and reduce the expression of genes related to iron uptake systems. This latter effect may contribute to the need for higher concentrations of CFDC to inhibit growth. The presence of human urine (HU), which contains low albumin concentrations, did not modify MIC values of two carbapenem-resistant A. baumannii. Levels of resistance to CFDC were not modified by HU in strain AMA40 but were reduced in strain AB5075. Expanding the studies to other carbapenem-resistant A. baumannii isolates showed that the presence of HU resulted in unmodified or reduced MIC of CDFC values. The expression of piuA, pirA, bauA, and bfnH determined by qRT-PCR was enhanced in A. baumannii AMA40 and AB5075 by the presence of HU in the culture medium. All four tested genes code for functions related to recognition and transport of ferric-siderophore complexes. The effect of HU on expression of pbp1, pbp3, blaOXA-51-like, blaADC, and blaNDM-1, genes associated with resistance to β-lactams, as well as genes coding for efflux pumps and porins was variable, showing dependence with the strain analyzed. We conclude that the lack of significant concentrations of albumin and free iron in HU makes this fluid behave differently from others we tested. Unlike other albumin rich fluids, the presence of HU does not impact the antibacterial activity of CFDC when tested against A. baumannii.
  • ÍtemAcceso Abierto
    2-Mercaptomethyl-thiazolidines use conserved aromatic–S interactions to achieve broad-range inhibition of metallo-β-lactamases
    (Royal Society of Chemistry, 2021-01-05) Rossi, María Agustina; Martínez, Verónica; Hinchliffe, Philip; Mojica, María F.; Castillo, Valerie; Moreno, Diego M.; Smith, Ryan; Spellberg, Brad; Drusano, George L.; Banchio, Claudia; Bonomo, Robert A.; Spencer, James; Vila, Alejandro J.; Mahler, Graciela; https://orcid.org/0000-0003-4720-4070; https://orcid.org/0000-0002-3697-5219; https://orcid.org/0000-0001-8611-4743; https://orcid.org/0000-0002-1380-9824; https://orcid.org/0000-0001-5493-8537; https://orcid.org/0000-0002-4602-0571; https://orcid.org/0000-0002-7978-3233; https://orcid.org/0000-0003-0612-0516
    Infections caused by multidrug resistant (MDR) bacteria are a major public health threat. Carbapenems are among the most potent antimicrobial agents that are commercially available to treat MDR bacteria. Bacterial production of carbapenem-hydrolysing metallo-β-lactamases (MBLs) challenges their safety and efficacy, with subclass B1 MBLs hydrolysing almost all β-lactam antibiotics. MBL inhibitors would fulfil an urgent clinical need by prolonging the lifetime of these life-saving drugs. Here we report the synthesis and activity of a series of 2-mercaptomethyl-thiazolidines (MMTZs), designed to replicate MBL interactions with reaction intermediates or hydrolysis products. MMTZs are potent competitive inhibitors of B1 MBLs in vitro (e.g., Ki = 0.44 μM vs. NDM-1). Crystal structures of MMTZ complexes reveal similar binding patterns to the most clinically important B1 MBLs (NDM-1, VIM-2 and IMP-1), contrasting with previously studied thiol-based MBL inhibitors, such as bisthiazolidines (BTZs) or captopril stereoisomers, which exhibit lower, more variable potencies and multiple binding modes. MMTZ binding involves thiol coordination to the Zn(II) site and extensive hydrophobic interactions, burying the inhibitor more deeply within the active site than D/L-captopril. Unexpectedly, MMTZ binding features a thioether–π interaction with a conserved active-site aromatic residue, consistent with their equipotent inhibition and similar binding to multiple MBLs. MMTZs penetrate multiple Enterobacterales, inhibit NDM-1 in situ, and restore carbapenem potency against clinical isolates expressing B1 MBLs. Based on their inhibitory profile and lack of eukaryotic cell toxicity, MMTZs represent a promising scaffold for MBL inhibitor development. These results also suggest sulphur–π interactions can be exploited for general ligand design in medicinal chemistry.
  • ÍtemAcceso Abierto
    Induced Heteroresistance in Carbapenem-Resistant Acinetobacter baumannii (CRAB) via Exposure to Human Pleural Fluid (HPF) and Its Impact on Cefiderocol Susceptibility
    (MDPI, 2023-07-21) Mezcord, Vyanka; Escalante, Jenny; Nishimura, Brent; Traglia, German M.; Sharma, Rajnikant; Vallé, Quentin; Tuttobene, Marisel Romina; Subils, Tomás; Marin, Ingrid; Pasteran, Fernando; Actis, Luis A.; Tolmasky, Marcelo E.; Bonomo, Robert A.; Rao, Gauri; Ramírez, María Soledad; https://orcid.org/0000-0003-1896-8450; https://orcid.org/0000-0002-4780-5311; https://orcid.org/0000-0001-5840-5869; https://orcid.org/0000-0001-9644-9088; https://orcid.org/0000-0002-6298-7811; https://orcid.org/0000-0002-9904-7890
    Infections caused by Carbapenem-resistant Acinetobacter baumannii (CRAB) isolates, such as hospital-acquired pneumonia (HAP), bacteremia, and skin and soft tissue infections, among others, are particularly challenging to treat. Cefiderocol, a chlorocatechol-substituted siderophore antibiotic, was approved by the U.S. Food and Drug Administration (FDA) in 2019 and prescribed for the treatment of CRAB infections. Despite the initial positive treatment outcomes with this antimicrobial, recent studies reported a higher-than-average all-cause mortality rate in patients treated with cefiderocol compared to the best available therapy. The cause(s) behind these outcomes remains unconfirmed. A plausible hypothesis is heteroresistance, a phenotype characterized by the survival of a small proportion of cells in a population that is seemingly isogenic. Recent results have demonstrated that the addition of human fluids to CRAB cultures leads to cefiderocol heteroresistance. Here, we describe the molecular and phenotypic analyses of CRAB heteroresistant bacterial subpopulations to better understand the nature of the less-than-expected successful outcomes after cefiderocol treatment. Isolation of heteroresistant variants of the CRAB strain AMA40 was carried out in cultures supplemented with cefiderocol and human pleural fluid (HPF). Two AMA40 variants, AMA40 IHC1 and IHC2, were resistant to cefiderocol. To identify mutations and gene expression changes associated with cefiderocol heteroresistance, we subjected these variants to whole genome sequencing and global transcriptional analysis. We then assessed the impact of these mutations on the pharmacodynamic activity of cefiderocol via susceptibility testing, EDTA and boronic acid inhibition analysis, biofilm formation, and static time-kill assays. Heteroresistant variants AMA40 IHC1 and AMA40 IHC2 have 53 chromosomal mutations, of which 40 are common to both strains. None of the mutations occurred in genes associated with high affinity iron-uptake systems or β-lactam resistance. However, transcriptional analyses demonstrated significant modifications in levels of expression of genes associated with iron-uptake systems or β-lactam resistance. The blaNDM-1 and blaADC-2, as well as various iron-uptake system genes, were expressed at higher levels than the parental strain. On the other hand, the carO and ompA genes’ expression was reduced. One of the mutations common to both heteroresistant strains was mapped within ppiA, a gene associated with iron homeostasis in other species. Static time-kill assays demonstrated that supplementing cation-adjusted Mueller–Hinton broth with human serum albumin (HAS), the main protein component of HPF, considerably reduced cefiderocol killing activity for all three strains tested. Notably, collateral resistance to amikacin was observed in both variants. We conclude that exposing CRAB to fluids with high HSA concentrations facilitates the rise of heteroresistance associated with point mutations and transcriptional upregulation of genes coding for β-lactamases and biofilm formation. The findings from this study hold significant implications for understanding the emergence of CRAB resistance mechanisms against cefiderocol treatment. This understanding is vital for the development of treatment guidelines that can effectively address the challenges posed by CRAB infections.
  • ÍtemAcceso Abierto
    Selective inhibition of the amyloid matrix of Escherichia coli biofilms by a bifunctional microbial metabolite
    (Nature Research, 2023-10-19) Cordisco, Estefanía; Zanor, María Inés; Moreno, Diego M.; Serra, Diego Omar; https://orcid.org/0000-0002-6574-1702; https://orcid.org/0000-0002-8903-0673; https://orcid.org/0000-0001-5493-8537; https://orcid.org/0000-0002-3926-384X
    The propensity of bacteria to grow collectively in communities known as biofilms and their ability to overcome clinical treatments in this condition has become a major medical problem, emphasizing the need for anti-biofilm strategies. Antagonistic microbial interactions have extensively served as searching platforms for antibiotics, but their potential as sources for anti-biofilm compounds has barely been exploited. By screening for microorganisms that in agar-set pairwise interactions could antagonize Escherichia coli’s ability to form macrocolony biofilms, we found that the soil bacterium Bacillus subtilis strongly inhibits the synthesis of amyloid fibers –known as curli-, which are the primary extracellular matrix (ECM) components of E. coli biofilms. We identified bacillaene, a B. subtilis hybrid non-ribosomal peptide/polyketide metabolite, previously described as a bacteriostatic antibiotic, as the effector molecule. We found that bacillaene combines both antibiotic and anti-curli functions in a concentration-dependent order that potentiates the ecological competitiveness of B. subtilis, highlighting bacillaene as a metabolite naturally optimized for microbial inhibition. Our studies revealed that bacillaene inhibits curli by directly impeding the assembly of the CsgB and CsgA curli subunits into amyloid fibers. Moreover, we found that curli inhibition occurs despite E. coli attempts to reinforce its protective ECM by inducing curli genes via a RpoS-mediated competition sensing response trigged by the threatening presence of B. subtilis. Overall, our findings illustrate the relevance of exploring microbial interactions not only for finding compounds with unknown and unique activities, but for uncovering additional functions of compounds previously categorized as antibiotics.
  • ÍtemAcceso Abierto
    Factors associated with mortality among hospitalized patients with COVID-19 disease treated with convalescent plasma
    (American Society for Microbiology, 2023-11-08) Perichon, Armando M.; Acosta, Andrea; Di Tulio, Liliana; Munuce, María José; Pezzotto, Stella; Bottasso, Oscar; http://orcid.org/0000-0002-8472-7965
    The use of convalescent plasma (CP) for hospitalized patients with SARSCoV-2 infection might be a useful option in certain settings. Soon after the outbreak of COVID-19, the National Ministry of Health of Argentina recommended the use of CP transfusion for hospitalized patients with COVID-19 disease. Between 1 June and 3 October 2020, 480 patients, excluding those on invasive mechanical ventilation (IMV), received at least one CP infusion in the province of Santa Fe. We aimed to find factors associated with mortality among this cohort of patients. The median age was 60 years (interquartile range: 49–69 years) and 320 (66.7%) were males. Most of these patients (93.75%) received a single CP infusion, 82.1% and 95.6% before day 4 and day 7 of hospitalization, respectively. Anti-SARS-CoV-2 titers were determined in the CP units administered using Elecsys Anti-SARS-CoV-2 S assay. At 28 days of follow-up, 250 patients were discharged (52.1%), 131 (27.3%) remained hospitalized without and 16 (3.3%) with oxygen requirement, 27 (5.6%) were on IMV, and 56 (11.7%) had died. In the multivariate logistic regression analysis, the factors significantly associated with 28-day mortality were (i) requirement of IMV, (ii) the administration of CP after the third day of hospitalization, (iii) age, and (iv) number of comorbidities. The qualitative and quantitative analyses of antibodies against SARS-CoV-2 in the infused CP were not associated with mortality. Our findings may imply a seemingly favorable effect of CP administration among patients with severe COVID-19 disease when infused sooner after hospitalization.
  • ÍtemAcceso Abierto
    The iron content of human serum albumin nodulates the susceptibility of Acinetobacter baumannii to Cefiderocol
    (MDPI, 2023-02-20) Escalante, Jenny; Nishimura, Brent; Tuttobene, Marisel Romina; Subils, Tomás; Mezcord, Vyanka; Actis, Luis A.; Tolmasky, Marcelo E.; Bonomo, Robert A.; Ramírez, María Soledad
  • ÍtemAcceso Abierto
    Editorial: Cell polarity: Trafficking and regulatory events that determine cell asymmetry
    (Frontiers Media S.A., 2023-01-12) Zucchetti, Andrés E.; Goldenring, James R.; Larocca, María Cecilia
  • ÍtemAcceso Abierto
    A disordered region retains the full protease inhibitor activity and the capacity to induce CD8+ T cells in vivo of the oral vaccine adjuvant U-Omp19
    (Elsevier, 2022-09-06) Darriba, María Laura; Pueblas Castro, Celeste; Coria, Lorena M.; Bruno, Laura; Cerutti, María Laura; Otero, Lisandro H.; Chemes, Lucía B.; Rasia, Rodolfo M.; Klinke, Sebastián; Cassataro, Juliana; Pasquevich, Karina A.
  • ÍtemAcceso Abierto
    Longitudinal evolution of the Pseudomonas-Derived Cephalosporinase (PDC) structure and activity in a cystic fibrosis patient treated with b-Lactams
    (American Society for Microbiology, 2022-09-08) Colque, Claudia A.; Albarracín Orio, Andrea G.; Tomatis, Pablo E.; Dotta, Gina; Moreno, Diego M.; Hedemann, Laura G.; Hickman, Rachel A.; Sommer, Lea M.; Feliziani, Sofía; Moyano, Alejandro J.; Bonomo, Robert A.; Johansen, Helle K.; Molin, Soren; Vila, Alejandro J.; Smania, Andrea M.
  • ÍtemAcceso Abierto
    Human serum albumin (HSA) regulates the expression of histone-like nucleoid structure protein (H-NS) in Acinetobacter baumannii
    (Nature Research, 2022-08-27) Escalante, Jenny; Nishimura, Brent; Tuttobene, Marisel Romina; Subils, Tomás; Pimentel, Camila; Georgeos, Nardin; Sieira, Rodrigo; Bonomo, Robert A.; Tolmasky, Marcelo E.; Ramírez, María Soledad
  • ÍtemAcceso Abierto
    Human Serum Proteins and Susceptibility of Acinetobacter baumannii to Cefiderocol: Role of Iron Transport
    (MDPI, 2022-03-03) Le, Casin; Pimentel, Camila; Pasteran, Fernando; Tuttobene, Marisel Romina; Subils, Tomás; Escalante, Jenny; Nishimura, Brent; Arriaga, Susana; Carranza, Aimee; Mezcord, Vyanka; Vila, Alejandro J.; Corso, Alejandra; Actis, Luis A.; Tolmasky, Marcelo E.; Bonomo, Robert A.; Ramírez, María Soledad
  • ÍtemAcceso Abierto
    Hyponastic leaves 1 is required for proper establishment of auxin gradient in apical hooks
    (American Society of Plant Biologists, 2021-10-02) Vacs, Paula; Rasia, Rodolfo M.; González Schain, Nahuel
  • ÍtemAcceso Abierto
    Metallo-β-lactamases and a tug-of-war for the available zinc at the host–pathogen interface
    (Elsevier, 2022) Bahr, Guillermo; González, Lisandro J.; Vila, Alejandro J.
  • ÍtemAcceso Abierto
    The urgent need for metallo-β-lactamase inhibitors: an unattended global threat
    (Elsevier Ltd, 2021-07-08) Mojica, Maria F.; Rossi, María Agustina; Vila, Alejandro J.; Bonomo, Robert A.
  • ÍtemAcceso Abierto
    Deciphering the evolution of metallo-β-lactamases: A journey from the test tube to the bacterial periplasm
    (American Society for Biochemistry and Molecular Biology Inc., 2022-02-01) López, Carolina; Delmonti, Juliana; Bonomo, Robert A.; Vila, Alejandro J.
  • ÍtemAcceso Abierto
    Interaction of Acinetobacter baumannii with Human Serum Albumin: Does the host hetermine the outcome?
    (MDPI, 2021-07-08) Pimentel, Camila; Le, Casin; Tuttobene, Marisel Romina; Subils, Tomás; Bonomo, Robert A.; Tolmasky, Marcelo E.; Ramírez, María Soledad
  • ÍtemAcceso Abierto
    Histone-like nucleoid-structuring protein (H-NS) regulatory role in antibiotic resistance in Acinetobacter baumannii
    (Nature Research, 2021) Rodgers, Deja; Le, Casin; Pimentel, Camila; Tuttobene, Marisel Romina; Subils, Tomás; Escalante, Jenny; Nishimura, Brent; Vescovi, Eleonora García; Sieira, Rodrigo; Bonomo, Robert A.; Tolmasky, Marcelo E.; Ramírez, María Soledad
  • ÍtemAcceso Abierto
    Characterisation of ST25 NDM-1-producing Acinetobacter spp. strains leading the increase in NDM-1 emergence in Argentina
    (Elsevier, 2020-09-02) Rodgers, Deja; Pasteran, Fernando; Calderon, Manuel; Jaber, Sara; Traglia, German M.; Albornoz, Ezequiel; Corso, Alejandra; Vila, Alejandro J.; Bonomo, Robert A.; Adams, Mark D.; Ramírez, María Soledad
  • ÍtemAcceso Abierto
    A new model for Trypanosoma cruzi heme homeostasis depends on modulation of TcHTE protein expression
    (American Society for Biochemistry and Molecular Biology, 2020-07-23) Pagura, Lucas; Tevere, Evelyn; Merli, Marcelo Luciano; Cricco, Julia Alejandra
  • ÍtemAcceso Abierto
    Metallo-β-lactamase inhibitors inspired on snapshots from the catalytic mechanism
    (MDPI, 2020-06-03) Palacios, Antonela R.; Rossi, María Agustina; Mahler, Graciela S.; Vila, Alejandro J.