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1.
Oncol Res ; 32(8): 1257-1264, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39055890

RESUMEN

The Kirsten rat sarcoma virus-son of sevenless 1 (KRAS-SOS1) axis drives tumor growth preferentially in pancreatic, colon, and lung cancer. Now, KRAS G12C mutated tumors can be successfully treated with inhibitors that covalently block the cysteine of the switch II binding pocket of KRAS. However, the range of other KRAS mutations is not amenable to treatment and the G12C-directed agents Sotorasib and Adragrasib show a response rate of only approximately 40%, lasting for a mean period of 8 months. One approach to increase the efficacy of inhibitors is their inclusion into proteolysis-targeting chimeras (PROTACs), which degrade the proteins of interest and exhibit much higher antitumor activity through multiple cycles of activity. Accordingly, PROTACs have been developed based on KRAS- or SOS1-directed inhibitors coupled to either von Hippel-Lindau (VHL) or Cereblon (CRBN) ligands that invoke the proteasomal degradation. Several of these PROTACs show increased activity in vitro and in vivo compared to their cognate inhibitors but their toxicity in normal tissues is not clear. The CRBN PROTACs containing thalidomide derivatives cannot be tested in experimental animals. Resistance to such PROTACS arises through downregulation or inactivation of CRBN or factors of the functional VHL E3 ubiquitin ligase. Although highly active KRAS and SOS1 PROTACs have been formulated their clinical application remains difficult.


Asunto(s)
Proteolisis , Proteínas Proto-Oncogénicas p21(ras) , Proteína SOS1 , Humanos , Proteína SOS1/metabolismo , Proteína SOS1/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Animales , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/patología , Antineoplásicos/farmacología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Quimera Dirigida a la Proteólisis
2.
Biochem Biophys Res Commun ; 723: 150190, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-38838447

RESUMEN

Soil salinity pose a significant challenge to global agriculture, threatening crop yields and food security. Understanding the salt tolerance mechanisms of plants is crucial for improving their survival under salt stress. AFP2, a negative regulator of ABA signaling, has been shown to play a crucial role in salt stress tolerance during seed germination. Mutations in AFP2 gene lead to increased sensitivity to salt stress. However, the underline mechanisms by which AFP2 regulates seed germination under salt stress remain elusive. In this study, we identified a protein interaction between AFP2 and SOS2, a Ser/Thr protein kinase known to play a critical role in salt stress response. Using a combination of genetic, biochemical, and physiological approaches, we investigated the role of the SOS2-AFP2 module in regulating seed germination under salt stress. Our findings reveal that SOS2 physically interacts with AFP2 and stabilizes it, leading to the degradation of the ABI5 protein, a negative transcription factor in seed germination under salt stress. This study sheds light on previously unknown connections within salt stress and ABA signaling, paving the way for novel strategies to enhance plant resilience against environmental challenges.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Germinación , Estrés Salino , Semillas , Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Germinación/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteolisis/efectos de los fármacos , Tolerancia a la Sal/genética , Semillas/metabolismo , Semillas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Semillas/genética , Transducción de Señal/efectos de los fármacos
3.
Int J Mol Sci ; 25(11)2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38892328

RESUMEN

Curcumin is a natural compound that is considered safe and may have potential health benefits; however, its poor stability and water insolubility limit its therapeutic applications. Different strategies aim to increase its water solubility. Here, we tested the compound PVP-curcumin as a photosensitizer for antimicrobial photodynamic therapy (aPDT) as well as its potential to act as an adjuvant in antibiotic drug therapy. Gram-negative E. coli K12 and Gram-positive S. capitis were subjected to aPDT using various PVP-curcumin concentrations (1-200 µg/mL) and 475 nm blue light (7.5-45 J/cm2). Additionally, results were compared to aPDT using 415 nm blue light. Gene expression of recA and umuC were analyzed via RT-qPCR to assess effects on the bacterial SOS response. Further, the potentiation of Ciprofloxacin by PVP-curcumin was investigated, as well as its potential to prevent the emergence of antibiotic resistance. Both bacterial strains were efficiently reduced when irradiated with 415 nm blue light (2.2 J/cm2) and 10 µg/mL curcumin. Using 475 nm blue light, bacterial reduction followed a biphasic effect with higher efficacy in S. capitis compared to E. coli K12. PVP-curcumin decreased recA expression but had limited effect regarding enhancing antibiotic treatment or impeding resistance development. PVP-curcumin demonstrated effectiveness as a photosensitizer against both Gram-positive and Gram-negative bacteria but did not modulate the bacterial SOS response.


Asunto(s)
Antibacterianos , Ciprofloxacina , Curcumina , Fármacos Fotosensibilizantes , Rec A Recombinasas , Curcumina/farmacología , Fármacos Fotosensibilizantes/farmacología , Rec A Recombinasas/metabolismo , Rec A Recombinasas/genética , Ciprofloxacina/farmacología , Antibacterianos/farmacología , Fotoquimioterapia/métodos , Respuesta SOS en Genética/efectos de los fármacos , Escherichia coli K12/efectos de los fármacos , Escherichia coli K12/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Povidona/química , Povidona/farmacología , Pruebas de Sensibilidad Microbiana , Escherichia coli/efectos de los fármacos , Luz , Proteínas de Unión al ADN
4.
ACS Synth Biol ; 13(7): 2045-2059, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38934464

RESUMEN

As the availability of data sets increases, meta-analysis leveraging aggregated and interoperable data types is proving valuable. This study leveraged a meta-analysis workflow to identify mutations that could improve robustness to reactive oxygen species (ROS) stresses using an industrially important melatonin production strain as an example. ROS stresses often occur during cultivation and negatively affect strain performance. Cellular response to ROS is also linked to the SOS response and resistance to pH fluctuations, which is important to strain robustness in large-scale biomanufacturing. This work integrated more than 7000 E. coli adaptive laboratory evolution (ALE) mutations across 59 experiments to statistically associate mutated genes to 2 ROS tolerance ALE conditions from 72 unique conditions. Mutant oxyR, fur, iscR, and ygfZ were significantly associated and hypothesized to contribute fitness in ROS stress. Across these genes, 259 total mutations were inspected in conjunction with transcriptomics from 46 iModulon experiments. Ten mutations were chosen for reintroduction based on mutation clustering and coinciding transcriptional changes as evidence of fitness impact. Strains with mutations reintroduced into oxyR, fur, iscR, and ygfZ exhibited increased tolerance to H2O2 and acid stress and reduced SOS response, all of which are related to ROS. Additionally, new evidence was generated toward understanding the function of ygfZ, an uncharacterized gene. This meta-analysis approach utilized aggregated and interoperable multiomics data sets to identify mutations conferring industrially relevant phenotypes with the least drawbacks, describing an approach for data-driven strain engineering to optimize microbial cell factories.


Asunto(s)
Escherichia coli , Mutación , Estrés Oxidativo , Especies Reactivas de Oxígeno , Estrés Oxidativo/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Melatonina/metabolismo , Evolución Molecular Dirigida/métodos
5.
ISA Trans ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38890017

RESUMEN

This work explores the polynomial fuzzy stabilization for positive systems. The traditional quadratic Lyapunov function and basic stability analysis may not be favourable for stability investigation due to the absence of the positivity property and membership functions. Therefore, a fuzzy co-positive polynomial Lyapunov-Krasovskii (FCPL) function which considers the positivity is proposed firstly through an imperfect premise matching (IPM) approach. Secondly, the symbol transfer technique which takes into account fuzzy membership knowledge relaxes the stability conditions. The number of symbols is reduced by two constraints: (1) the last and next moments of the membership functions of the FCPL function; (2) membership functions of the fuzzy model and the controller. Finally, the polynomial fuzzy controller with symbols is obtained. Two examples are implemented to verify the proposed methods.

6.
Proc Natl Acad Sci U S A ; 121(27): e2407832121, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38935560

RESUMEN

In 1967, in this journal, Evelyn Witkin proposed the existence of a coordinated DNA damage response in Escherichia coli, which later came to be called the "SOS response." We revisited this response using the replication inhibitor azidothymidine (AZT) and RNA-Seq analysis and identified several features. We confirm the induction of classic Save our ship (SOS) loci and identify several genes, including many of the pyrimidine pathway, that have not been previously demonstrated to be DNA damage-inducible. Despite a strong dependence on LexA, these genes lack LexA boxes and their regulation by LexA is likely to be indirect via unknown factors. We show that the transcription factor "stringent starvation protein" SspA is as important as LexA in the regulation of AZT-induced genes and that the genes activated by SspA change dramatically after AZT exposure. Our experiments identify additional LexA-independent DNA damage inducible genes, including 22 small RNA genes, some of which appear to activated by SspA. Motility and chemotaxis genes are strongly down-regulated by AZT, possibly as a result of one of more of the small RNAs or other transcription factors such as AppY and GadE, whose expression is elevated by AZT. Genes controlling the iron siderophore, enterobactin, and iron homeostasis are also strongly induced, independent of LexA. We confirm that IraD antiadaptor protein is induced independent of LexA and that a second antiadaptor, IraM is likewise strongly AZT-inducible, independent of LexA, suggesting that RpoS stabilization via these antiadaptor proteins is an integral part of replication stress tolerance.


Asunto(s)
Daño del ADN , Replicación del ADN , Proteínas de Escherichia coli , Escherichia coli , Regulación Bacteriana de la Expresión Génica , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Replicación del ADN/efectos de los fármacos , Respuesta SOS en Genética/efectos de los fármacos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Serina Endopeptidasas
7.
Adv Exp Med Biol ; 1441: 761-775, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38884747

RESUMEN

Lesions of the semilunar valve and the aortic arch can occur either in isolation or as part of well-described clinical syndromes. The polygenic cause of calcific aortic valve disease will be discussed including the key role of NOTCH1 mutations. In addition, the complex trait of bicuspid aortic valve disease will be outlined, both in sporadic/familial cases and in the context of associated syndromes, such as Alagille, Williams, and Kabuki syndromes. Aortic arch abnormalities particularly coarctation of the aorta and interrupted aortic arch, including their association with syndromes such as Turner and 22q11 deletion, respectively, are also discussed. Finally, the genetic basis of congenital pulmonary valve stenosis is summarized, with particular note to Ras-/mitogen-activated protein kinase (Ras/MAPK) pathway syndromes and other less common associations, such as Holt-Oram syndrome.


Asunto(s)
Aorta Torácica , Válvula Aórtica , Humanos , Aorta Torácica/anomalías , Aorta Torácica/patología , Válvula Aórtica/anomalías , Válvula Aórtica/patología , Anomalías Múltiples/genética , Anomalías Múltiples/patología , Cardiopatías Congénitas/genética , Cardiopatías Congénitas/patología , Enfermedad de la Válvula Aórtica Bicúspide/genética , Estenosis de la Válvula Pulmonar/genética , Mutación , Receptor Notch1/genética , Enfermedad de la Válvula Aórtica/genética , Enfermedades de las Válvulas Cardíacas/genética , Enfermedades de las Válvulas Cardíacas/patología , Calcinosis/genética , Calcinosis/patología , Enfermedades Hematológicas/genética , Enfermedades Hematológicas/patología , Enfermedades Vestibulares/genética , Enfermedades Vestibulares/patología
8.
Curr Issues Mol Biol ; 46(5): 4787-4802, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38785556

RESUMEN

Hematopoietic stem cell transplantation (HSCT) remains a cornerstone in the management of patients with hematological malignancies. Endothelial injury syndromes, such as HSCT-associated thrombotic microangiopathy (HSCT-TMA), veno-occlusive disease/sinusoidal obstruction syndrome (SOS/VOD), and capillary leak syndrome (CLS), constitute complications after HSCT. Moreover, endothelial damage is prevalent after immunotherapy with chimeric antigen receptor-T (CAR-T) and can be manifested with cytokine release syndrome (CRS) or immune effector cell-associated neurotoxicity syndrome (ICANS). Our literature review aims to investigate the genetic susceptibility in endothelial injury syndromes after HSCT and CAR-T cell therapy. Variations in complement pathway- and endothelial function-related genes have been associated with the development of HSCT-TMA. In these genes, CFHR5, CFHR1, CFHR3, CFI, ADAMTS13, CFB, C3, C4, C5, and MASP1 are included. Thus, patients with these variations might have a predisposition to complement activation, which is also exaggerated by other factors (such as acute graft-versus-host disease, infections, and calcineurin inhibitors). Few studies have examined the genetic susceptibility to SOS/VOD syndrome, and the implicated genes include CFH, methylenetetrahydrofolate reductase, and heparinase. Finally, specific mutations have been associated with the onset of CRS (PFKFB4, CX3CR1) and ICANS (PPM1D, DNMT3A, TE2, ASXL1). More research is essential in this field to achieve better outcomes for our patients.

9.
Bioorg Med Chem Lett ; 107: 129780, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38714262

RESUMEN

Oncogenic KRAS mutations drive an approximately 25 % of all human cancers. Son of Sevenless 1 (SOS1), a critical guanine nucleotide exchange factor, catalyzes the activation of KRAS. Targeting SOS1 degradation has engaged as a promising therapeutic strategy for KRAS-mutant cancers. Herein, we designed and synthesized a series of novel CRBN-recruiting SOS1 PROTACs using the pyrido[2,3-d]pyrimidin-7-one-based SOS1 inhibitor as the warhead. One representative compound 11o effectively induced the degradation of SOS1 in three different KRAS-mutant cancer cell lines with DC50 values ranging from 1.85 to 7.53 nM. Mechanism studies demonstrated that 11o-induced SOS1 degradation was dependent on CRBN and proteasome. Moreover, 11o inhibited the phosphorylation of ERK and displayed potent anti-proliferative activities against SW620, A549 and DLD-1 cells. Further optimization of 11o may provide us promising SOS1 degraders with favorable drug-like properties for developing new chemotherapies targeting KRAS-driven cancers.


Asunto(s)
Antineoplásicos , Proliferación Celular , Diseño de Fármacos , Proteína SOS1 , Humanos , Proteína SOS1/metabolismo , Proteína SOS1/antagonistas & inhibidores , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Relación Estructura-Actividad , Línea Celular Tumoral , Estructura Molecular , Ensayos de Selección de Medicamentos Antitumorales , Relación Dosis-Respuesta a Droga , Pirimidinas/farmacología , Pirimidinas/síntesis química , Pirimidinas/química , Pirimidinonas/farmacología , Pirimidinonas/síntesis química , Pirimidinonas/química , Quimera Dirigida a la Proteólisis
10.
Ann Transl Med ; 12(2): 29, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38721455

RESUMEN

Simulated operations (SOs) are a direct application of the Integral Theory (IT) mantras, "structure and function are related" and "restore the structure and you will improve the function". SOs performed in a clinic setting, are the most effective way possible to test the validity of the IT predictions: stress urinary incontinence (SUI) and urge are mainly caused by laxity in the vagina or its supporting ligaments. The SUI prediction of the IT is validated if a hemostat applied vaginally in the position of the midurethra to mechanically support the pubourethral ligament (PUL) immediately stops urine loss on coughing. The urge and chronic pelvic pain (CPP) predictions of the IT are similarly validated if a patient states her urge and pain symptoms are relieved by insertion of the bottom blade of a bivalve speculum which supports the uterosacral ligaments (USLs). An important use of SOs is to preoperatively assess (by the hemostat test) whether sling surgery for SUI is likely to cure the patient. Similarly, the speculum is very useful for diagnosing whether severe urge or pain symptoms in a woman with minimal prolapse are originating from weak USLs. If digital support of a cystocele relieves urge symptoms, the patient can reasonably be informed that a cystocele repair should improve the urge as well her cystocele prolapse. Used intraoperatively under spinal anesthesia, SOs can determine whether a sling is sufficiently tight to reverse the loose PUL which is causing the SUI. Approximating both cardinal ligaments (CLs) intraoperatively can result in a remarkable disappearance of a transverese defect cystocele; approximating USLs intraoperatively can give an indication of how effective a USL plication would be surgically.

11.
Biochem Biophys Res Commun ; 716: 150009, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38697010

RESUMEN

The SOS response is a condition that occurs in bacterial cells after DNA damage. In this state, the bacterium is able to reсover the integrity of its genome. Due to the increased level of mutagenesis in cells during the repair of DNA double-strand breaks, the SOS response is also an important mechanism for bacterial adaptation to the antibiotics. One of the key proteins of the SOS response is the SMC-like protein RecN, which helps the RecA recombinase to find a homologous DNA template for repair. In this work, the localization of the recombinant RecN protein in living Escherichia coli cells was revealed using fluorescence microscopy. It has been shown that the RecN, outside the SOS response, is predominantly localized at the poles of the cell, and in dividing cells, also localized at the center. Using in vitro methods including fluorescence microscopy and optical tweezers, we show that RecN predominantly binds single-stranded DNA in an ATP-dependent manner. RecN has both intrinsic and single-stranded DNA-stimulated ATPase activity. The results of this work may be useful for better understanding of the SOS response mechanism and homologous recombination process.


Asunto(s)
ADN Bacteriano , Escherichia coli , Microscopía Fluorescente , Imagen Individual de Molécula , Microscopía Fluorescente/métodos , Escherichia coli/genética , Escherichia coli/metabolismo , Imagen Individual de Molécula/métodos , ADN Bacteriano/metabolismo , ADN Bacteriano/genética , Respuesta SOS en Genética , ADN de Cadena Simple/metabolismo , ADN de Cadena Simple/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Unión Proteica , Rec A Recombinasas/metabolismo , Rec A Recombinasas/genética , Pinzas Ópticas
12.
Am J Chin Med ; 52(3): 885-904, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716619

RESUMEN

Polyphyllin VII is a biologically active herbal monomer extracted from the traditional Chinese herbal medicine Chonglou. Many studies have demonstrated the anticancer activity of polyphyllin VII against various types of cancers, such as colon, liver, and lung cancer, but its effect on breast cancer has not been elucidated. In this study, we demonstrate that polyphyllin VII inhibited proliferation, increased production of intracellular reactive oxygen species, and decreased mitochondrial membrane potential in breast cancer cells. Notably, polyphyllin VII also induced apoptosis via the mitochondrial pathway. Transcriptome sequencing was used to analyze the targets of PPVII in regulating breast cancer cells. Mechanistic studies showed that polyphyllin VII downregulated Son of Sevenless1 (SOS1) and inhibited the MAPK/ERK pathway. Furthermore, PPVII exerted strong antitumor effects in vivo in nude mice injected with breast cancer cells. Our results suggest that PPVII may promote apoptosis through regulating the SOS1/MAPK/ERK pathway, making it a possible candidate target for the treatment of breast cancer.


Asunto(s)
Apoptosis , Neoplasias de la Mama , Regulación hacia Abajo , Sistema de Señalización de MAP Quinasas , Proteína SOS1 , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Animales , Humanos , Femenino , Regulación hacia Abajo/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína SOS1/metabolismo , Proteína SOS1/genética , Ratones Desnudos , Saponinas/farmacología , Saponinas/uso terapéutico , Proliferación Celular/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Ratones , Línea Celular Tumoral , Medicamentos Herbarios Chinos/farmacología , Fitoterapia , Antineoplásicos Fitogénicos/farmacología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos BALB C
13.
Environ Sci Technol ; 58(21): 9017-9030, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38753980

RESUMEN

A myriad of nonantibiotic compounds is released into the environment, some of which may contribute to the dissemination of antimicrobial resistance by stimulating conjugation. Here, we analyzed a collection of studies to (i) identify patterns of transfer stimulation across groups and concentrations of chemicals, (ii) evaluate the strength of evidence for the proposed mechanisms behind conjugal stimulation, and (iii) examine the plausibility of alternative mechanisms. We show that stimulatory nonantibiotic compounds act at concentrations from 1/1000 to 1/10 of the minimal inhibitory concentration for the donor strain but that stimulation is always modest (less than 8-fold). The main proposed mechanisms for stimulation via the reactive oxygen species/SOS cascade and/or an increase in cell membrane permeability are not unequivocally supported by the literature. However, we identify the reactive oxygen species/SOS cascade as the most likely mechanism. This remains to be confirmed by firm molecular evidence. Such evidence and more standardized and high-throughput conjugation assays are needed to create technologies and solutions to limit the stimulation of conjugal gene transfer and contribute to mitigating global antibiotic resistance.


Asunto(s)
Conjugación Genética , Especies Reactivas de Oxígeno/metabolismo , Antibacterianos/farmacología , Transferencia de Gen Horizontal
14.
Cancers (Basel) ; 16(10)2024 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-38791980

RESUMEN

Preclinical studies rarely test the efficacy of therapies in both sexes. The field of oncology is no exception in this regard. In a model of syngeneic, orthotopic, metastasized pancreatic ductal adenocarcinoma we evaluated the impact of sex on pathological features of this disease as well as on the efficacy and possible adverse side effects of a novel, small molecule-based therapy inhibiting KRAS:SOS1, MEK1/2 and PI3K signaling in male and female C57BL/6J mice. Male mice had less tumor infiltration of CD8-positive cells, developed bigger tumors, had more lung metastasis and a lower probability of survival compared to female mice. These more severe pathological features in male animals were accompanied by higher distress at the end of the experiment. The evaluated inhibitors BI-3406, trametinib and BKM120 showed synergistic effects in vitro. This combinatorial therapy reduced tumor weight more efficiently in male animals, although the drug concentrations were similar in the tumors of both sexes. These results underline the importance of sex-specific preclinical research and at the same time provide a solid basis for future studies with the tested compounds.

15.
J Comput Chem ; 45(23): 1968-1979, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38703360

RESUMEN

A computational methodology, founded on chemical concepts, is presented for interpreting the role of nuclear motion in the electron transport through single-molecule junctions (SMJ) using many-electron ab initio quantum chemical calculations. Within this approach the many-electron states of the system, computed at the SOS-ADC(2) level, are followed along the individual normal modes of the encapsulated molecules. The inspection of the changes in the partial charge distribution of the many-electron states allows the quantification of the electron transport and the estimation of transmission probabilities. This analysis improves the understanding of the relationship between internal motions and electron transport. Two SMJ model systems are studied for validation purposes, constructed from a conductor (BDA, benzene-1,4-diamine) and an insulator molecule (DABCO, 1,4-diazabicyclo[2.2.2]octane). The trends of the resulting transmission probabilities are in agreement with the experimental observations, demonstrating the capability of the approach to distinguish between conductor and insulator type systems, thereby offering a straightforward and cost-effective tool for such classifications via quantum chemical calculations.

16.
Plant Mol Biol ; 114(3): 57, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743266

RESUMEN

A high concentration of sodium (Na+) is the primary stressor for plants in high salinity environments. The Salt Overly Sensitive (SOS) pathway is one of the best-studied signal transduction pathways, which confers plants the ability to export too much Na+ out of the cells or translocate the cytoplasmic Na+ into the vacuole. In this study, the Salt Overly Sensitive3 (MpSOS3) gene from Pongamia (Millettia pinnata Syn. Pongamia pinnata), a semi-mangrove, was isolated and characterized. The MpSOS3 protein has canonical EF-hand motifs conserved in other calcium-binding proteins and an N-myristoylation signature sequence. The MpSOS3 gene was significantly induced by salt stress, especially in Pongamia roots. Expression of the wild-type MpSOS3 but not the mutated nonmyristoylated MpSOS3-G2A could rescue the salt-hypersensitive phenotype of the Arabidopsis sos3-1 mutant, which suggested the N-myristoylation signature sequence of MpSOS3 was required for MpSOS3 function in plant salt tolerance. Heterologous expression of MpSOS3 in Arabidopsis accumulated less H2O2, superoxide anion radical (O2-), and malondialdehyde (MDA) than wild-type plants, which enhanced the salt tolerance of transgenic Arabidopsis plants. Under salt stress, MpSOS3 transgenic plants accumulated a lower content of Na+ and a higher content of K+ than wild-type plants, which maintained a better K+/Na+ ratio in transgenic plants. Moreover, no development and growth discrepancies were observed in the MpSOS3 heterologous overexpression plants compared to wild-type plants. Our results demonstrated that the MpSOS3 pathway confers a conservative salt-tolerant role and provided a foundation for further study of the SOS pathway in Pongamia.


Asunto(s)
Arabidopsis , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Plantas Modificadas Genéticamente , Tolerancia a la Sal , Plantas Tolerantes a la Sal , Plantas Tolerantes a la Sal/genética , Plantas Tolerantes a la Sal/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Tolerancia a la Sal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Cloruro de Sodio/farmacología , Secuencia de Aminoácidos , Filogenia , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Estrés Salino/genética , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo
17.
Front Microbiol ; 15: 1379534, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38659986

RESUMEN

Introduction/objective: Suppression of the SOS response in combination with drugs damaging DNA has been proposed as a potential target to tackle antimicrobial resistance. The SOS response is the pathway used to repair bacterial DNA damage induced by antimicrobials such as quinolones. The extent of lexA-regulated protein expression and other associated systems under pressure of agents that damage bacterial DNA in clinical isolates remains unclear. The aim of this study was to assess the impact of this strategy consisting on suppression of the SOS response in combination with quinolones on the proteome profile of Escherichia coli clinical strains. Materials and methods: Five clinical isolates of E. coli carrying different chromosomally- and/or plasmid-mediated quinolone resistance mechanisms with different phenotypes were selected, with E. coli ATCC 25922 as control strain. In addition, from each clinical isolate and control, a second strain was created, in which the SOS response was suppressed by deletion of the recA gene. Bacterial inocula from all 12 strains were then exposed to 1xMIC ciprofloxacin treatment (relative to the wild-type phenotype for each isogenic pair) for 1 h. Cell pellets were collected, and proteins were digested into peptides using trypsin. Protein identification and label-free quantification were done by liquid chromatography-mass spectrometry (LC-MS) in order to identify proteins that were differentially expressed upon deletion of recA in each strain. Data analysis and statistical analysis were performed using the MaxQuant and Perseus software. Results: The proteins with the lowest expression levels were: RecA (as control), AphA, CysP, DinG, DinI, GarL, PriS, PsuG, PsuK, RpsQ, UgpB and YebG; those with the highest expression levels were: Hpf, IbpB, TufB and RpmH. Most of these expression alterations were strain-dependent and involved DNA repair processes and nucleotide, protein and carbohydrate metabolism, and transport. In isolates with suppressed SOS response, the number of underexpressed proteins was higher than overexpressed proteins. Conclusion: High genomic and proteomic variability was observed among clinical isolates and was not associated with a specific resistant phenotype. This study provides an interesting approach to identify new potential targets to combat antimicrobial resistance.

18.
Int J Mol Sci ; 25(8)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38674008

RESUMEN

Cysteine and its derivatives, including H2S, can influence bacterial virulence and sensitivity to antibiotics. In minimal sulfate media, H2S is generated under stress to prevent excess cysteine and, together with incorporation into glutathione and export into the medium, is a mechanism of cysteine homeostasis. Here, we studied the features of cysteine homeostasis in LB medium, where the main source of sulfur is cystine, whose import can create excess cysteine inside cells. We used mutants in the mechanisms of cysteine homeostasis and a set of microbiological and biochemical methods, including the real-time monitoring of sulfide and oxygen, the determination of cysteine and glutathione (GSH), and the expression of the Fur, OxyR, and SOS regulons genes. During normal growth, the parental strain generated H2S when switching respiration to another substrate. The mutations affected the onset time, the intensity and duration of H2S production, cysteine and glutathione levels, bacterial growth and respiration rates, and the induction of defense systems. Exposure to chloramphenicol and high doses of ciprofloxacin increased cysteine content and GSH synthesis. A high inverse relationship between log CFU/mL and bacterial growth rate before ciprofloxacin addition was revealed. The study points to the important role of maintaining cysteine homeostasis during normal growth and antibiotic exposure in LB medium.


Asunto(s)
Antibacterianos , Ciprofloxacina , Cisteína , Escherichia coli , Glutatión , Homeostasis , Cisteína/metabolismo , Ciprofloxacina/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/crecimiento & desarrollo , Homeostasis/efectos de los fármacos , Glutatión/metabolismo , Antibacterianos/farmacología , Medios de Cultivo/química , Sulfuro de Hidrógeno/metabolismo , Sulfuro de Hidrógeno/farmacología , Mutación , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos
19.
Bioorg Med Chem Lett ; 105: 129745, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38614151

RESUMEN

A series of 8 novel pyridinyl 4-(2-oxoimidazolidin-1-yl)benzenesulfonates (PYRIB-SOs) were designed, prepared and evaluated for their mechanism of action. PYRIB-SOs were found to have antiproliferative activity in the nanomolar to submicromolar range on several breast cancer cell lines. Moreover, subsequent biofunctional assays indicated that the most potent PYRIB-SOs 1-3 act as antimitotics binding to the colchicine-binding site (C-BS) of α, ß-tubulin and that they arrest the cell cycle progression in the G2/M phase. Microtubule immunofluorescence and tubulin polymerisation assay confirm that they disrupt the cytoskeleton through inhibition of tubulin polymerisation as observed with microtubule-destabilising agents. They also show good overall theoretical physicochemical, pharmacokinetic and druglike properties. Overall, these results show that PYRIB-SOs is a new family of promising antimitotics to be further studied in vivo for biopharmaceutical and pharmacodynamic evaluations.


Asunto(s)
Antimitóticos , Proliferación Celular , Colchicina , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Colchicina/química , Colchicina/metabolismo , Colchicina/farmacología , Sitios de Unión , Antimitóticos/farmacología , Antimitóticos/química , Antimitóticos/síntesis química , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Bencenosulfonatos/química , Bencenosulfonatos/farmacología , Bencenosulfonatos/síntesis química , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Tubulina (Proteína)/metabolismo , Estructura Molecular , Moduladores de Tubulina/farmacología , Moduladores de Tubulina/química , Moduladores de Tubulina/síntesis química , Piridinas/química , Piridinas/farmacología , Piridinas/síntesis química , Relación Dosis-Respuesta a Droga
20.
Microbiol Res ; 284: 127711, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38636240

RESUMEN

Microbial ferroptosis has been proved to combat drug-resistant pathogens, but whether this pattern can be applied to the prevention and control of Escherichia coli remains to be further explored. In this study, ferrous gluconate (FeGlu) showed remarkable efficacy in killing E. coli MG1655 with a mortality rate exceeding 99.9%, as well as enterotoxigenic E. coli H10407 (ETEC H10407) and enterohemorrhagic E. coli O157:H7 (EHEC O157:H7). Bacteria death was instigated by the infiltration of Fe2+, accompanied by a burst of intracellular reactive oxygen species (ROS) and lipid peroxidation. Notably, mitigating lipid peroxidation failed to alleviate death of E. coli. Further findings confirmed that FeGlu induced DNA damage, and ΔrecA mutant showed more sensitive, implicating that DNA damage was involved in the death of E. coli. The direct interaction of Fe2+ with DNA was demonstrated by fluorescent staining, gel electrophoresis, and circular dichroism (CD). Moreover, proteomic analysis unveiled 50 differentially expressed proteins (DEPs), including 18 significantly down-regulated proteins and 32 significantly up-regulated proteins. Among them, the down-regulation of SOS-responsive transcriptional suppressor LexA indicated DNA damage induced severely by FeGlu. Furthermore, FeGlu influenced pathways such as fatty acid metabolism (FadB, FadE), iron-sulfur cluster assembly (IscA, IscU, YadR), iron binding, and DNA-binding transcription, along with α-linolenic acid metabolism, fatty acid degradation, and pyruvate metabolism. These pathways were related to FeGlu stress, including lipid peroxidation and DNA damage. In summary, FeGlu facilitated ferroptosis in E. coli through mechanisms involving lipid peroxidation and DNA damage, which presents a new strategy for the development of innovative antimicrobial strategies targeting E. coli infections.


Asunto(s)
Daño del ADN , Escherichia coli , Ferroptosis , Compuestos Ferrosos , Peroxidación de Lípido , Especies Reactivas de Oxígeno , Ferroptosis/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Compuestos Ferrosos/metabolismo , Compuestos Ferrosos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Antibacterianos/farmacología , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Proteómica , Escherichia coli O157/efectos de los fármacos , Escherichia coli O157/genética , Escherichia coli O157/metabolismo
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