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1.
Nucleic Acids Res ; 51(15): 7900-7913, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37462073

RESUMO

PHO84 is a budding yeast gene reported to be negatively regulated by its cognate antisense transcripts both in cis and in trans. In this study, we performed Transient-transcriptome sequencing (TT-seq) to investigate the correlation of sense/antisense pairs in a dbp2Δ strain and found over 700 sense/antisense pairs, including PHO84, to be positively correlated, contrasting the prevailing model. To define what mechanism regulates the PHO84 gene and how this regulation could have been originally attributed to repression by the antisense transcript, we conducted a series of molecular biology and genetics experiments. We now report that the 3' untranslated region (3'UTR) of PHO84 plays a repressive role in sense expression, an activity not linked to the antisense transcripts. Moreover, we provide results of a genetic screen for 3'UTR-dependent repression of PHO84 and show that the vast majority of identified factors are linked to negative regulation. Finally, we show that the PHO84 promoter and terminator form gene loops which correlate with transcriptional repression, and that the RNA-binding protein, Tho1, increases this looping and the 3'UTR-dependent repression. Our results negate the current model for antisense non-coding transcripts of PHO84 and suggest that many of these transcripts are byproducts of open chromatin.


Assuntos
RNA Antissenso , Saccharomyces cerevisiae , Regiões 3' não Traduzidas/genética , Cromatina , Genômica , RNA Antissenso/genética , RNA Antissenso/metabolismo , Saccharomyces cerevisiae/metabolismo , Regulação Fúngica da Expressão Gênica
2.
BMC Plant Biol ; 24(1): 237, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38566021

RESUMO

BACKGROUND: Onions are economically and nutritionally important vegetable crops. Despite advances in technology and acreage, Indian onion growers face challenges in realizing their full productivity potential. This study examines the technical efficiency of onion growers, the factors influencing it, and the constraints faced by those adopting drip irrigation in the Ghod river basin of western Maharashtra. A sample of 480 farmers including those practicing drip irrigation and those not practicing it, was selected from Junnar, Shirur, Parner, and Shrigonda blocks of the basin. The primary data was collected through semi-structured interviews. Analytical tools such as the Cobb-Douglas production function (represents technological relationship between multiple inputs and the resulting output), a single-stage stochastic frontier model, the Tobit model, and descriptive statistics were used to assess the technical efficiency of onion production at the farm level. RESULTS: According to the maximum likelihood estimates of the stochastic frontier analysis, drip adopters exhibited a mean technical efficiency of 92%, while for non-adopters it was 65%. It indicates that the use of drip irrigation technology is associated with higher technical efficiency. The association of technical efficiency and socio-economic characters of households showed that education, extension contacts, social participation, and use of information sources had a positive influence on technical efficiency, while family size had a negative influence on the drip irrigation adopters. For non-drip adopters, significant positive effects were observed for landholding, extension contact, and information source use. The major constraints faced by drip system adopters included a lack of knowledge about the proper operating techniques for drip systems and the cost of maintenance. CONCLUSION: The differences with inputs associated with two irrigation methods showed that the response of inputs to increase onion yield is greater for farmers who use drip irrigation than for farmers who do not, and are a result of the large differences in the technical efficiencies. These inefficiencies and other limitations following the introduction of drip irrigation, such as lack of knowledge about the proper operations, need to be addressed through tailored training for farmers and further interventions.


Assuntos
Irrigação Agrícola , Cebolas , Irrigação Agrícola/métodos , Índia , Fazendas , Produtos Agrícolas
3.
Semin Dial ; 37(3): 269-272, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38418259

RESUMO

Stenosis in the anastomotic site or venous limb of an arteriovenous fistula (AVF) is the most frequent cause of AVF failure. Percutaneous angioplasty with a standard or high-pressure balloon is the first-line treatment for AVF stenosis due to its higher technical success rate (90%) and lower complication rate (4%). Almost 20% of stenosis cases are resistant or undilatable by regular-pressure balloon angioplasty due to fibrosis, leading to technical failure or restenosis. Alternative therapies, such as atherectomy devices or cutting balloons, are expensive and difficult to obtain in low-income developing countries. We successfully treated resistant AVF stenosis with a coronary OPN-NC® ultra-high-pressure balloon and produced a good angiographic result with technical success. Coronary hardware is easily available and relatively cheaper compared to dedicated peripheral balloons or devices in our country due to reuse, which can be a boon in such type of cases. According to the standard hospital protocol, Cathlab hardware was reused.


Assuntos
Angioplastia com Balão , Derivação Arteriovenosa Cirúrgica , Análise Custo-Benefício , Humanos , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Angioplastia com Balão/economia , Oclusão de Enxerto Vascular/terapia , Oclusão de Enxerto Vascular/economia , Oclusão de Enxerto Vascular/etiologia , Masculino , Diálise Renal , Feminino , Pobreza , Pessoa de Meia-Idade , Constrição Patológica
4.
J Appl Microbiol ; 135(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38178631

RESUMO

AIMS: We aimed to investigate the prevalence, pathology, and characterization of Streptococcus dysgalactiae subsp. equisimilis (SDSE) in slaughtered pigs of India. METHODS AND RESULTS: We collected 1254 morbid tissues (lungs-627 and spleen-627) and 627 heart-blood from 627 slaughtered pigs. The bacterial isolation, antibiogram, virulence gene profiling, and mouse pathogenicity testing were performed for the detection and characterization of SDSE. A total of 177 isolates (heart-blood-160 and tissues-17) were recovered from 627 slaughtered pigs with higher isolation rate in heart-blood (25.51%). The prevalence of SDSE was 11% in morbid tissues by polymerase chain reaction. Majority of isolates showed higher detection of streptolysin O, followed by streptokinase and extracellular phospholipase A virulence genes with higher degree of resistance to azithromycin, clindamycin, erythromycin, and penicillin antibiotics. Mouse pathogenicity testing confirmed virulence based on histopathological lesions and re-isolation of SDSE. CONCLUSIONS: Our findings highlight the high prevalence of SDSE in slaughtered pigs. The presence of virulence genes and mouse pathogenicity testing confirm their pathogenic potential.


Assuntos
Antibacterianos , Infecções Estreptocócicas , Streptococcus , Animais , Suínos , Camundongos , Virulência/genética , Antibacterianos/farmacologia , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/microbiologia , Farmacorresistência Bacteriana/genética
5.
Sensors (Basel) ; 24(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39123940

RESUMO

Physical therapy is often essential for complete recovery after injury. However, a significant population of patients fail to adhere to prescribed exercise regimens. Lack of motivation and inconsistent in-person visits to physical therapy are major contributing factors to suboptimal exercise adherence, slowing the recovery process. With the advancement of virtual reality (VR), researchers have developed remote virtual rehabilitation systems with sensors such as inertial measurement units. A functional garment with an integrated wearable sensor can also be used for real-time sensory feedback in VR-based therapeutic exercise and offers affordable remote rehabilitation to patients. Sensors integrated into wearable garments offer the potential for a quantitative range of motion measurements during VR rehabilitation. In this research, we developed and validated a carbon nanocomposite-coated knit fabric-based sensor worn on a compression sleeve that can be integrated with upper-extremity virtual rehabilitation systems. The sensor was created by coating a commercially available weft knitted fabric consisting of polyester, nylon, and elastane fibers. A thin carbon nanotube composite coating applied to the fibers makes the fabric electrically conductive and functions as a piezoresistive sensor. The nanocomposite sensor, which is soft to the touch and breathable, demonstrated high sensitivity to stretching deformations, with an average gauge factor of ~35 in the warp direction of the fabric sensor. Multiple tests are performed with a Kinarm end point robot to validate the sensor for repeatable response with a change in elbow joint angle. A task was also created in a VR environment and replicated by the Kinarm. The wearable sensor can measure the change in elbow angle with more than 90% accuracy while performing these tasks, and the sensor shows a proportional resistance change with varying joint angles while performing different exercises. The potential use of wearable sensors in at-home virtual therapy/exercise was demonstrated using a Meta Quest 2 VR system with a virtual exercise program to show the potential for at-home measurements.


Assuntos
Articulação do Cotovelo , Nanocompostos , Realidade Virtual , Dispositivos Eletrônicos Vestíveis , Humanos , Nanocompostos/química , Articulação do Cotovelo/fisiologia , Robótica/instrumentação , Nanotubos de Carbono/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Amplitude de Movimento Articular/fisiologia , Carbono/química
6.
Chemistry ; 29(40): e202300566, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37042421

RESUMO

Although Metal oxide ZnO is widely used as electron transport layers in all-inorganic PSCs due to high electron mobility, high transmittance, and simple preparation processing, the surface defects of ZnO suppress the quality of perovskite film and inhibit the solar cells' performance. In this work, [6,6]-Phenyl C61 butyric acid (PCBA) modified zinc oxide nanorods (ZnO NRs) is employed as electron transport layer in perovskite solar cells. The resulting perovskite film coated on the zinc oxide nanorods has better crystallinity and uniformity, facilitating charge carrier transportation, reducing recombination losses, and ultimately improving the cells' performance. The perovskite solar cell with the device configuration of ITO/ZnO nanorods/PCBA/CsPbIBr2 /Spiro-OMeTAD/Au delivers a high short circuit current density of 11.83 mA cm-2 and power conversion efficiency of 12.05 %.

7.
Virus Genes ; 59(1): 67-78, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36357764

RESUMO

Swine is considered as a suitable sentinel to predict Japanese encephalitis virus (JEV) outbreaks in humans. The present study was undertaken to determine the circulating genotypes of JEV in swine population of India. A total of 702 swine serum samples from four states of western, northern, northern-temperate, and north-eastern zones of India were screened by real-time RT-PCR targeting envelope gene of JEV, which showed positivity of 35.33%. The viral copy number ranged from 3 copies to 6.3 × 104 copies/reaction. Subsequently, the capsid/prM structural gene region of JEV positive samples was amplified by nested RT-PCR, sequenced, and genetically characterized. The phylogenetic analysis of the partial sequences of the capsid gene of 42 JEV positive samples showed that they all belonged to genotype-III (G-III) of JEV. Notably, JEV positive swine samples showed high nucleotide identity with human isolates from China and Nepal which explains the probable spillover of infection between neighboring countries probably by migratory birds. The novel mutations were observed in JEV positive sample B8 at C54 position (Phe → Ser), and JEV positive sample K50 at C62 (Thr → Ala) and C65 (Leu → Pro) positions which were absent from other JEV isolates reported till now. The mutation at the C66 position (Leu → Ser) observed in live attenuated vaccine SA14-14-2 strain was not found in JEV positive samples of our study. The detection of the G-III JE virus from climatically diverse states of India reinforces the need to continue the ongoing human vaccination program in India by extending vaccine coverage in temperate states.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Humanos , Animais , Suínos , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/epidemiologia , Encefalite Japonesa/veterinária , Filogenia , Genótipo , Índia/epidemiologia , Vacinas Atenuadas , Proteínas do Capsídeo/genética
8.
Microb Pathog ; 173(Pt A): 105790, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36170950

RESUMO

Turkey arthritis reovirus (TARV) has been established as a cause of lameness in meat type turkeys in the past decade. However, no information is available on the age susceptibility of TARV or its transmission dynamics. We conducted this study to determine the age at which turkey poults are susceptible to TARV infection and whether infected birds can horizontally transmit the virus to their non-infected pen mates (sentinels). Five groups of turkeys were orally inoculated with TARV (∼106 TCID50/ml) at 2, 7, 14, 21 and 28 days of age (DOA). Two days after each challenge, four uninfected sentinel turkeys of equal age were added to the virus-inoculated groups. At one- and two-weeks post infection, turkeys from each group, including two sentinels, were euthanized followed by necropsy. Inoculated birds in all age groups had TARV replication in the intestine and gastrocnemius tendon with no statistically significant variation at p < 0.5. Furthermore, the inoculated birds at different age groups showed consistently high gastrocnemius tendon histologic lesion scores while birds in the 28-days-old age group had numerically lower lesion scores at 14 days post inoculation (dpi). The sentinels, in turn, also showed virus replication in their intestines and tendons and histologic lesions in gastrocnemius tendons. The findings indicate that turkeys at the age of 28 days or less are susceptible to infection with TARV following oral challenge. It was also found that TARV-infected birds could transmit the infection to naïve sentinel turkeys of the same age.


Assuntos
Artrite , Doenças das Aves Domésticas , Infecções por Reoviridae , Reoviridae , Animais , Perus , Anticorpos Antivirais
9.
Avian Pathol ; 51(5): 435-444, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35583932

RESUMO

Turkey reoviruses have been implicated in multiple disease syndromes resulting in significant economic losses to the turkey industry. It has been known for decades that turkey enteric reovirus (TERV) is involved in poult enteritis complex, but turkey arthritis reovirus (TARV), the causative agent of tenosynovitis in turkeys, emerged in 2011. In 2019, we isolated reovirus from several cases of hepatitis in turkeys and tentatively named it turkey hepatitis reovirus (THRV). The comparative pathogenesis of these viruses, and correlation with their genetic make-up (if any), is not known. In this study, we inoculated nine groups of 1-week-old turkey poults with two THRV, five TARV and two TERV via oral route. A tenth group served as a negative control. A subset of birds from each group was euthanised at 3, 5, 7, 14, 21, and 28 days post-inoculation (dpi). Tissues were collected for histology and real-time RT-PCR. All nine viruses were found to be enterotropic; the virus gene copy number in the intestine reached a peak at 5 dpi followed by a sharp decline at 7 dpi. All viruses caused a significant decline in body weight gain of birds as compared to the negative control group. Both TARV and THRV strains replicated in tendons and produced histologic lesions consistent with tenosynovitis. Hepatic lesions were produced by THRV only and the virus was re-isolated from liver and spleen of inoculated birds fulfilling Koch's postulates. The results of this study should be helpful in facilitating diagnosis and designing future mitigation plans.


Assuntos
Artrite , Doenças das Aves Domésticas , Infecções por Reoviridae , Reoviridae , Tenossinovite , Animais , Anticorpos Antivirais , Artrite/veterinária , Reoviridae/genética , Infecções por Reoviridae/veterinária , Tenossinovite/veterinária , Perus
10.
Sensors (Basel) ; 22(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36433205

RESUMO

Here, we report the synthesis of the WS2 nanorods (NRs) using an eco-friendly and facile hydrothermal method for an acetone-sensing application. This study explores the acetone gas-sensing characteristics of the WS2 nanorod sensor for 5, 10, and 15 ppm concentrations at 25 °C, 50 °C, 75 °C, and 100 °C. The WS2 nanorod sensor shows the highest sensitivity of 94.5% at 100 °C for the 15 ppm acetone concentration. The WS2 nanorod sensor also reveals the outstanding selectivity of acetone compared to other gases, such as ammonia, ethanol, acetaldehyde, methanol, and xylene at 100 °C with a 15 ppm concentration. The estimated selectivity coefficient indicates that the selectivity of the WS2 nanorod acetone sensor is 7.1, 4.5, 3.7, 2.9, and 2.0 times higher than xylene, acetaldehyde, ammonia, methanol, and ethanol, respectively. In addition, the WS2 nanorod sensor also divulges remarkable stability of 98.5% during the 20 days of study. Therefore, it is concluded that the WS2 nanorod can be an excellent nanomaterial for developing acetone sensors for monitoring work/public places.


Assuntos
Acetona , Nanotubos , Amônia , Xilenos , Metanol , Gases , Etanol , Acetaldeído
11.
Indian J Microbiol ; 62(4): 627-633, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36458219

RESUMO

This study reports a rare fatal case of Chromobacterium violeceum OUAT_2017 strain infection in an Asiatic elephant calf in India. Necropsy revealed pus-filled nodules in liver, spleen, and lungs. Nutrient broth cultures of nodule content showed sediment of violet pigment whereas smooth, non-diffusible, violet-pigmented, homogeneous colonies appeared on nutrient agar. The organism was found to be non-haemolytic and resistant to 8 of the 24 antibiotics tested in vitro. Partial 16S rRNA gene sequence measuring 1410 bp revealed 97% homology with C. violeceum. The bacterial genome composed of 64.87% of G + C content with total size of 4,681,202 bp. The genome annotation has 42 genes responsible for multidrug antibiotic resistance with the presence of Aminoglycoside-modifying enzymes (AAC (6')) that targets streptomycin and spectinomycin. Our findings corroborated the lethal effect of C. violeceum in a new host (elephant) that enriched scientific information on epidemiological picture and whole genome sequencing as well. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-022-01047-4.

12.
J Biol Chem ; 295(27): 8988-8998, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32376686

RESUMO

DEAD-box helicase 5 (DDX5) is a founding member of the DEAD-box RNA helicase family, a group of enzymes that regulate ribonucleoprotein formation and function in every aspect of RNA metabolism, ranging from synthesis to decay. Our laboratory previously found that DDX5 is involved in energy homeostasis, a process that is altered in many cancers. Small cell lung cancer (SCLC) is an understudied cancer type for which effective treatments are currently unavailable. Using an array of methods, including short hairpin RNA-mediated gene silencing, RNA and ChIP sequencing analyses, and metabolite profiling, we show here that DDX5 is overexpressed in SCLC cell lines and that its down-regulation results in various metabolic and cellular alterations. Depletion of DDX5 resulted in reduced growth and mitochondrial dysfunction in the chemoresistant SCLC cell line H69AR. The latter was evidenced by down-regulation of genes involved in oxidative phosphorylation and by impaired oxygen consumption. Interestingly, DDX5 depletion specifically reduced intracellular succinate, a TCA cycle intermediate that serves as a direct electron donor to mitochondrial complex II. We propose that the oncogenic role of DDX5, at least in part, manifests as up-regulation of respiration supporting the energy demands of cancer cells.


Assuntos
RNA Helicases DEAD-box/metabolismo , Mitocôndrias/metabolismo , Carcinoma de Pequenas Células do Pulmão/metabolismo , Linhagem Celular Tumoral , Citoplasma/metabolismo , RNA Helicases DEAD-box/fisiologia , Humanos , Mitocôndrias/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Helicases/metabolismo , RNA Interferente Pequeno/metabolismo , Ribonucleoproteínas/metabolismo
13.
J Biol Chem ; 295(52): 18316-18327, 2020 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-33109600

RESUMO

Pyrroline-5-carboxylate reductase 1 (PYCR1) catalyzes the biosynthetic half-reaction of the proline cycle by reducing Δ1-pyrroline-5-carboxylate (P5C) to proline through the oxidation of NAD(P)H. Many cancers alter their proline metabolism by up-regulating the proline cycle and proline biosynthesis, and knockdowns of PYCR1 lead to decreased cell proliferation. Thus, evidence is growing for PYCR1 as a potential cancer therapy target. Inhibitors of cancer targets are useful as chemical probes for studying cancer mechanisms and starting compounds for drug discovery; however, there is a notable lack of validated inhibitors for PYCR1. To fill this gap, we performed a small-scale focused screen of proline analogs using X-ray crystallography. Five inhibitors of human PYCR1 were discovered: l-tetrahydro-2-furoic acid, cyclopentanecarboxylate, l-thiazolidine-4-carboxylate, l-thiazolidine-2-carboxylate, and N-formyl l-proline (NFLP). The most potent inhibitor was NFLP, which had a competitive (with P5C) inhibition constant of 100 µm The structure of PYCR1 complexed with NFLP shows that inhibitor binding is accompanied by conformational changes in the active site, including the translation of an α-helix by 1 Å. These changes are unique to NFLP and enable additional hydrogen bonds with the enzyme. NFLP was also shown to phenocopy the PYCR1 knockdown in MCF10A H-RASV12 breast cancer cells by inhibiting de novo proline biosynthesis and impairing spheroidal growth. In summary, we generated the first validated chemical probe of PYCR1 and demonstrated proof-of-concept for screening proline analogs to discover inhibitors of the proline cycle.


Assuntos
Neoplasias da Mama/metabolismo , Inibidores Enzimáticos/farmacologia , Prolina/análogos & derivados , Pirrolina Carboxilato Redutases/antagonistas & inibidores , Pirrolina Carboxilato Redutases/metabolismo , Neoplasias da Mama/patologia , Domínio Catalítico , Cristalografia por Raios X , Feminino , Humanos , Fenótipo , Células Tumorais Cultivadas , delta-1-Pirrolina-5-Carboxilato Redutase
14.
Arch Biochem Biophys ; 703: 108852, 2021 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-33771508

RESUMO

Pyrroline-5-carboxylate reductase (PYCR in humans) catalyzes the final step of l-proline biosynthesis by catalyzing the reduction of L-Δ1-pyrroline-5-carboxylate (L-P5C) to l-proline using NAD(P)H as the hydride donor. In humans, three isoforms PYCR1, PYCR2, and PYCR3 are known. Recent genome-wide association and clinical studies have revealed that homozygous mutations in human PYCR2 lead to postnatal microcephaly and hypomyelination, including hypomyelinating leukodystrophy type 10. To uncover biochemical and structural insights into human PYCR2, we characterized the steady-state kinetics of the wild-type enzyme along with two protein variants, Arg119Cys and Arg251Cys, that were previously identified in patients with microcephaly and hypomyelination. Kinetic measurements with PYCR2 suggest a sequential binding mechanism with L-P5C binding before NAD(P)H and NAD(P)+ releasing before L-Pro. Both disease-related variants are catalytically impaired. Depending on whether NADPH or NADH was used, the catalytic efficiency of the R119C protein variant was 40 or 366 times lower than that of the wild-type enzyme, while the catalytic efficiency of the R251C protein variant was 7 or 26 times lower than that of the wild-type enzyme. In addition, thermostability and circular dichroism measurements suggest that the R251C protein variant has a pronounced folding defect. These results are consistent with the involvement of Arg119Cys and Arg251Cys in disease pathology.


Assuntos
Doença/genética , Mutação , Pirrolina Carboxilato Redutases/genética , Estabilidade Enzimática , Humanos , Cinética , Estrutura Secundária de Proteína , Pirrolina Carboxilato Redutases/química , Pirrolina Carboxilato Redutases/metabolismo , Temperatura
15.
Amino Acids ; 53(12): 1863-1874, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34792644

RESUMO

L-Thioproline (L-thiazolidine-4-carboxylate, L-T4C) is a cyclic sulfur-containing analog of L-proline found in multiple kingdoms of life. The oxidation of L-T4C leads to L-cysteine formation in bacteria, plants, mammals, and protozoa. The conversion of L-T4C to L-Cys in bacterial cell lysates has been attributed to proline dehydrogenase and L-Δ1-pyrroline-5-carboxylate (P5C) reductase (PYCR) enzymes but detailed kinetic studies have not been conducted. Here, we characterize the dehydrogenase activity of human PYCR isozymes 1 and 2 with L-T4C using NAD(P)+ as the hydride acceptor. Both PYCRs exhibit significant L-T4C dehydrogenase activity; however, PYCR2 displays nearly tenfold higher catalytic efficiency (136 M-1 s-1) than PYCR1 (13.7 M-1 s-1). Interestingly, no activity was observed with either L-Pro or the analog DL-thiazolidine-2-carboxylate, indicating that the sulfur at the 4-position is critical for PYCRs to utilize L-T4C as a substrate. Inhibition kinetics show that L-Pro is a competitive inhibitor of PYCR1 [Formula: see text] with respect to L-T4C, consistent with these ligands occupying the same binding site. We also confirm by mass spectrometry that L-T4C oxidation by PYCRs leads to cysteine product formation. Our results suggest a new enzyme function for human PYCRs in the metabolism of L-T4C.


Assuntos
Pirrolina Carboxilato Redutases/metabolismo , Tiazolidinas/metabolismo , Sítios de Ligação/fisiologia , Cisteína/metabolismo , Humanos , Cinética , Prolina/metabolismo , Pirróis/metabolismo
16.
Mol Biol Rep ; 48(6): 5371-5376, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34232463

RESUMO

BACKGROUND: Enterococci are ubiquitous microorganisms having diverse ecological niches but most prominently in gastrointestinal tract of humans and animals. Production of enterocins makes them a good probiotic candidate. However, their role as probiotics has become ambiguous in the last few years because of the presence of virulence factors and antibiotic resistance genes. These virulence traits are known to be transferred genetically, which makes them opportunistic pathogens in the gastrointestinal tract leading to serious concerns about their being used as probiotics. In the present study, Enterococcusspp. isolated from the human gut were subjected to Whole-Genome Sequencing (WGS) to determine the presence of resistance and virulence genes. METHODS AND RESULTS: Four human origins Enterococcus spp. including Enterococcus faecalis, Enterococcus casseliflavus, and two Enterococcus gallinarum were isolated from human fecal samples and further cultured on blood agar. Sanger sequencing was done using Applied Biosystems 3730xl DNA Analyzer. These strains were further subjected to WGS using oxford nanopore technology MinION. Raw data were analyzed using the free online tool epi2me. The Comprehensive Antibiotic Resistance Database (CARD) and RAST (Rapid Annotation using Subsystem Technology) software were used to look for the presence of antibiotic resistance genes in these strains. Resistance determinants for clinically important antibiotics (vancomycin) and functional virulence factor genes were detected. G-view server was used for comparative genomics of all strains. CONCLUSION: The genomic sequencing of Enterococcus suggested that E. faecalis, E. casseliflavus, and E. gallinarum strains are opportunistic pathogens, having antibiotic resistance genes. All isolates had vancomycin resistance genes, which were expressed phenotypically. Genes related to bacteriocin resistance were also present in E. casseliflavus and E. gallinarum.


Assuntos
Farmacorresistência Bacteriana/genética , Enterococcus/genética , Virulência/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Enterococcus/patogenicidade , Enterococcus faecalis/genética , Fezes , Microbioma Gastrointestinal/genética , Genômica/métodos , Humanos , Testes de Sensibilidade Microbiana , Probióticos/farmacologia , Fatores de Virulência/genética , Sequenciamento Completo do Genoma/métodos
17.
Int J Mol Sci ; 22(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34445643

RESUMO

The development and spread of antibiotics and biocides resistance is a significant global challenge. To find a solution for this emerging problem, the discovery of novel bacterial cellular targets and the critical pathways associated with antimicrobial resistance is needed. In the present study, we investigated the role of the two most critical envelope stress response regulators, RpoE and CpxR, on the physiology and susceptibility of growing Salmonella enterica serovar enteritidis cells using the polycationic antimicrobial agent, chlorhexidine (CHX). It was shown that deletion of the cpxR gene significantly increased the susceptibility of this organism, whereas deletion of the rpoE gene had no effect on the pathogen's susceptibility to this antiseptic. It has been shown that a lack of the CpxR regulator induces multifaceted stress responses not only in the envelope but also in the cytosol, further affecting the key biomolecules, including DNA, RNA, and proteins. We showed that alterations in cellular trafficking and most of the stress responses are associated with a dysfunctional CpxR regulator during exponential growth phase, indicating that these physiological changes are intrinsically associated with the lack of the CpxR regulator. In contrast, induction of type II toxin-antitoxin systems and decrease of abundances of enzymes and proteins associated with the recycling of muropeptides and resistance to polymixin and cationic antimicrobial peptides were specific responses of the ∆cpxR mutant to the CHX treatment. Overall, our study provides insight into the effects of CpxR on the physiology of S. Enteritidis cells during the exponential growth phase and CHX treatment, which may point to potential cellular targets for the development of an effective antimicrobial agent.


Assuntos
Anti-Infecciosos Locais/farmacologia , Proteínas de Bactérias/metabolismo , Clorexidina/farmacologia , Regulação Bacteriana da Expressão Gênica , Salmonella enteritidis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Mutação , Proteoma/análise , Proteoma/metabolismo , Salmonella enteritidis/efeitos dos fármacos , Salmonella enteritidis/metabolismo
18.
Biochemistry ; 59(36): 3285-3289, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32841567

RESUMO

Protein biochemistry protocols typically include disulfide bond reducing agents to guard against unwanted thiol oxidation and protein aggregation. Commonly used disulfide bond reducing agents include dithiothreitol, ß-mercaptoethanol, glutathione, and the tris(alkyl)phosphine compounds tris(2-carboxyethyl)phosphine (TCEP) and tris(3-hydroxypropyl)phosphine (THPP). While studying the catalytic activity of the NAD(P)H-dependent enzyme Δ1-pyrroline-5-carboxylate reductase, we unexpectedly observed a rapid non-enzymatic chemical reaction between NAD+ and the reducing agents TCEP and THPP. The product of the reaction exhibits a maximum ultraviolet absorbance peak at 334 nm and forms with an apparent association rate constant of 231-491 M-1 s-1. The reaction is reversible, and nuclear magnetic resonance characterization (1H, 13C, and 31P) of the product revealed a covalent adduct between the phosphorus of the tris(alkyl)phosphine reducing agent and the C4 atom of the nicotinamide ring of NAD+. We also report a 1.45 Å resolution crystal structure of short-chain dehydrogenase/reductase with the NADP+-TCEP reaction product bound in the cofactor binding site, which shows that the adduct can potentially inhibit enzymes. These findings serve to caution researchers when using TCEP or THPP in experimental protocols with NAD(P)+. Because NAD(P)+-dependent oxidoreductases are widespread in nature, our results may be broadly relevant.


Assuntos
Burkholderia/enzimologia , Ditiotreitol/química , NAD/metabolismo , Fosfinas/química , Substâncias Redutoras/química , Redutases-Desidrogenases de Cadeia Curta/química , Redutases-Desidrogenases de Cadeia Curta/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Dissulfetos/química , Oxirredução , Conformação Proteica , Domínios Proteicos
19.
Vet Pathol ; 57(2): 296-310, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32096438

RESUMO

Cervidpoxvirus is one of the more recently designated genera within the subfamily Chordopoxvirinae, with Deerpox virus (DPV) as the only recognized species to date. In this study, the authors describe spontaneous disease and infection in the North American moose (Alces americanus) by a novel Cervidpoxvirus, here named Moosepox virus (MPV). Three 4-month-old moose calves developed a multifocal subacute-to-chronic, necrotizing, suppurative-to-granulomatous dermatitis that affected the face and the extremities. Ultrastructurally, all stages of MPV morphogenesis-that is, crescents, spherical immature particles, mature particles, and enveloped mature virus-were observed in skin tissue. In vitro infection with MPV confirmed that its morphogenesis was similar to that of the prototype vaccinia virus. The entire coding region, including 170 putative genes of this MPV, was sequenced and annotated. The sequence length was 164,258 bp with 98.5% nucleotide identity with DPV (strain W-1170-84) based on the whole genome. The genome of the study virus was distinct from that of the reference strain (W-1170-84) in certain genes, including the CD30-like protein (83.9% nucleotide, 81.6% amino acid), the endothelin precursor (73.2% nucleotide including some indels, 51.4% amino acid), and major histocompatibility class (MHC) class I-like protein (81.0% nucleotide, 68.2% amino acid). This study provides biological characterization of a new Cervidpoxvirus attained through in vivo and in vitro ultrastructural analyses. It also demonstrates the importance of whole-genome sequencing in the molecular characterization of poxviruses identified in taxonomically related hosts.


Assuntos
Chordopoxvirinae/genética , Cervos/virologia , Dermatite/veterinária , Genoma Viral/genética , Animais , Chordopoxvirinae/isolamento & purificação , Chordopoxvirinae/ultraestrutura , Dermatite/diagnóstico por imagem , Dermatite/patologia , Dermatite/virologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Masculino , Microscopia Eletrônica de Transmissão/veterinária , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária , Pele/patologia , Pele/virologia , Sequenciamento Completo do Genoma/veterinária
20.
Food Microbiol ; 85: 103307, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31500711

RESUMO

Cold atmospheric-gaseous plasma (CAP) is an emerging non-thermal technology for decontamination of foodborne bacterial and viral pathogens. We obtained a >5 log10 reduction in the titer (TCID50) of feline calicivirus (FCV) on stainless steel discs and Romaine lettuce leaves after 3 min wet exposure to air plasma generated by a two-dimensional array of integrated coaxial-microhollow dielectric barrier discharge (2D-AICM-DBD). However, when human norovirus (HuNoV GII.4) was treated for 5 min under the same conditions, ~2.6 log10 (>99.5%) reduction in genome copy number was observed as measured by ethidium monoazide-coupled RT-qPCR (EMA-RT-qPCR). To assess this discrepancy, we studied CAP's effect on FCV by the cell culture method and by the EMA-coupled RT-qPCR method. It was found that the molecular titration method (EMA-RT-qPCR) underestimates the level of virus reduction by CAP. Additionally, the fecal matter present in HuNoV samples partially suppressed virucidal activity of CAP. Assuming that the lower virus reduction measured by EMA-RT-qPCR method compared to cell culture method for FCV is the same as for HuNoV, we can conclude that FCV may be used as a surrogate for HuNoV to assess the virucidal effect of CAP. CAP is able to inactivate 3.5 Log10 units of HuNoV at low titers after 2 min of exposure.


Assuntos
Fezes/virologia , Norovirus/efeitos dos fármacos , Gases em Plasma/farmacologia , Inativação de Vírus/efeitos dos fármacos , Azidas , Calicivirus Felino/efeitos dos fármacos , Calicivirus Felino/genética , Desinfecção/métodos , Humanos , Lactuca/virologia , Norovirus/genética , Reação em Cadeia da Polimerase em Tempo Real , Aço Inoxidável
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