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1.
Protein J ; 43(3): 437-446, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38492187

RESUMO

Universal stress proteins (USPs) are widely distributed and play crucial roles in cellular responses to biotic and abiotic stresses. These roles include regulating cell growth and development, cell motility, hypoxia responses, and ion sequestration. With the increasing frequency and intensity of extreme weather events due to climate change, pathogens have developed different strategies to withstand environmental stresses, in which USPs play a significant role in their survival and virulence. In this study, we analyzed the importance of USPs in various organisms, such as archaea, plants, and fungi, as a parameter that influences their survival. We discussed the different types Of USPs and their role, aiming to carry out fundamental research in this field to identify significant constraints for better understanding of USP functions at molecular level. Additionally, we discussed concepts and research techniques that could help overcome these hurdles and facilitate new molecular approaches to better understand and target USPs as important stress adaptation and survival regulators. Although the precise characteristics of USPs are still unclear, numerous innovative uses have already been developed, tested, and implemented. Complementary approaches to basic research and applications, as well as new technology and analytical techniques, may offer insights into the cryptic but crucial activities of USPs in various living systems.


Assuntos
Proteínas de Bactérias , Proteínas de Choque Térmico , Proteínas de Plantas , Bactérias/genética , Bactérias/metabolismo , Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biotecnologia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas/química , Plantas/genética , Plantas/metabolismo , Estresse Fisiológico
2.
Biochem Genet ; 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427123

RESUMO

Salmonella Typhimurium (ST) is a zoonotic pathogen that can cause gastroenteritis in humans when they consume contaminated food or water. When exposed to various stressors, both from living organisms (biotic) and the environment (abiotic), Salmonella Typhimurium produces Universal Stress Proteins (USPs). These proteins are gaining recognition for their crucial role in bacterial stress resistance and the ability to enter a prolonged state of growth arrest. Additionally, USPs exhibit diverse structures due to the fusion of the USP domain with different catalytic motifs, enabling them to participate in various reactions and cellular activities during stressful conditions. In this particular study, researchers cloned and analyzed the uspA gene obtained from poultry-derived strains of Salmonella Typhimurium. The gene comprises 435 base pairs, encoding a USP family protein consisting of 144 amino acids. Phylogenetic analysis demonstrated a close relationship between the uspA genes of Salmonella Typhimurium and those found in other bacterial species. We used molecular dynamics simulations and 3D structure prediction to ensure that the USPA protein was stable. Furthermore, we also carried out motif search and network analysis of protein-protein interactions. The findings from this study offer valuable insights for the development of inhibitors targeted against Salmonella Typhimurium.

3.
Microb Pathog ; 181: 106182, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37263448

RESUMO

Efflux proteins are transporter molecules that actively pump out a variety of substrates, including antibiotics, from cells to the environment. They are found in both Gram-positive and Gram-negative bacteria and eukaryotic cells. Based on their protein sequence homology, energy source, and overall structure, efflux proteins can be divided into seven groups. Multidrug efflux pumps are transmembrane proteins produced by microbes to enhance their survival in harsh environments and contribute to antibiotic resistance. These pumps are present in all bacterial genomes studied, indicating their ancestral origins. Many bacterial genes encoding efflux pumps are involved in transport, a significant contributor to antibiotic resistance in microbes. Efflux pumps are widely implicated in the extrusion of clinically relevant antibiotics from cells to the extracellular environment and, as such, represent a significant challenge to antimicrobial therapy. This review aims to provide an overview of the structures and mechanisms of action, substrate profiles, regulation, and possible inhibition of clinically relevant efflux pumps. Additionally, recent advances in research and the pharmacological exploitation of efflux pump inhibitors as a promising intervention for combating drug resistance will be discussed.


Assuntos
Proteínas de Bactérias , Bactérias Gram-Negativas , Proteínas de Bactérias/metabolismo , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/metabolismo
4.
World J Microbiol Biotechnol ; 39(6): 162, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37067651

RESUMO

Salmonella enterica serovar Typhimurium is becoming a leading cause of gastroenteritis and mortality. The use of antibiotics has increased natural resistance of S. Typhimurium to antibiotics. This study aims to isolate and characterize multi-drug-resistant (MDR) Salmonella strains from hospital sewage samples in Bhopal City, central India. The MDR isolates were characterized by molecular identification, antimicrobial resistance patterns, multi-locus sequence typing, and efflux pump activity. Specific genes (hilA, stn, invA, typh, and iroB) were used to confirm S. Typhimurium isolates. The Kirbey-Bauer method was employed to profile antimicrobial resistance using 20 antibiotics. Multi-locus sequence typing confirmed S. Typhimurium using seven housekeeping genes (aroC, dnaN, hemD, hisD, purE, sucA, and thr). Out of five strains, only four were confirmed as S. Typhimurium during MLST analysis. Efflux pump activity was determined using the ethidium bromide (EtBr) cartwheel test. Of the 160 isolates, 38 were presumptively confirmed as S. Typhimurium based on biochemical characterization, and only five MDR Salmonella strains were selected for their resistance against most antibiotics. Efflux pump activity revealed that five out of the four MDR isolates did not retain EtBr inside the cells, indicating pronounced efflux activity. Additionally, the isolated strains showed a specific correlation between the antimicrobial phenotypes and genotypes. The results of this study provide a better understanding of the characterization of S. Typhimurium serotype in Bhopal City. Future studies should focus on understanding changing antimicrobial resistance patterns, pathogenicity, and the genetic background of Salmonella serotypes. Further surveillance activities for antimicrobial-resistant Salmonella in different environmental sources should be prioritized.


Assuntos
Infecções por Salmonella , Salmonella typhimurium , Humanos , Salmonella typhimurium/genética , Tipagem de Sequências Multilocus , Esgotos , Antibacterianos/farmacologia , Infecções por Salmonella/epidemiologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla/genética
5.
Biomedicines ; 10(7)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35884849

RESUMO

From infancy through to old age, the microbiome plays an important role in modulating the host-immune system. As we age, our immune system and our gut microbiota change significantly in composition and function, which is linked to an increased vulnerability to infectious diseases and a decrease in vaccine responses. Our microbiome remains largely stable throughout adulthood; however, aging causes a major shift in the composition and function of the gut microbiome, as well as a decrease in diversity. Considering the critical role of the gut microbiome in the host-immune system, it is important to address, prevent, and ameliorate age-related dysbiosis, which could be an effective strategy for preventing/restoring functional deficits in immune responses as we grow older. Several factors, such as the host's genetics and nutritional state, along with the gut microbiome, can influence vaccine efficacy or reaction. Emerging evidence suggests that the microbiome could be a significant determinant of vaccine immunity. Physiological mechanisms such as senescence, or the steady loss of cellular functions, which affect the aging process and vaccination responses, have yet to be comprehended. Recent studies on several COVID-19 vaccines worldwide have provided a considerable amount of data to support the hypothesis that aging plays a crucial role in modulating COVID-19 vaccination efficacy across different populations.

6.
Nutrients ; 14(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35565691

RESUMO

Type-2 diabetes mellitus (T2DM) is often linked with hyperglycemia, disturbed lipid profiles, inflammation, and gut dysbiosis. Omega-3 fatty acid supplementation has a vital role in the management of T2DM. As a result, a better understanding of the potential role of omega-3 fatty acids in the development and progression of T2DM by influencing the intestinal microflora will help to improve the therapeutic intervention for T2DM and related complications. Focusing on the molecular mechanisms and signaling pathways induced by omega-3 fatty acids, this paper attempts to comprehensively review and discuss the putative associations between omega-3 fatty acids, gut dysbiosis, and the pathophysiology of T2DM and its related comorbidities. In addition, we contemplate the importance of gut microbiota in T2DM prevention and treatment and ponder the role of omega-3 fatty acids in T2DM by positively modulating gut microbiota, which may lead to discovery of novel targets and therapeutic strategies thereby paving way for further comprehensive, mechanistic, and clinical studies.


Assuntos
Diabetes Mellitus Tipo 2 , Ácidos Graxos Ômega-3 , Microbioma Gastrointestinal , Hiperglicemia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/prevenção & controle , Disbiose/prevenção & controle , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Ômega-3/uso terapêutico , Microbioma Gastrointestinal/fisiologia , Humanos , Hiperglicemia/tratamento farmacológico
7.
Arch Microbiol ; 203(9): 5509-5517, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34417854

RESUMO

Salmonella Typhimurium (ST) is a Gram-negative zoonotic pathogenic bacterium that causes infectious disease in humans as well as in animals. It causes foodborne diarrheal or gastrointestinal illness and fever called salmonellosis, which is a leading cause of millions of deaths worldwide. Salmonellaenterica serovar Typhimurium (S. Typhimurium) during its pathogenesis take away the actin cytoskeleton of their host cells and this is the crucial step of its infection cycle. Cyclophilin A, a type of peptidyl-prolyl isomerase that's encoded by the ppiA gene in ST, plays pleiotropic roles in maintaining bacterial physiology. In this investigation, the proteomic characterization of the peptidyl-prolyl cis-trans isomerase- A (Cyclophilin A) from Salmonella Typhimurium is reported. Cyclophilin A (CypA) protein from Salmonella Typhimurium proved to be highly conserved and homologous protein sequence compared to other organisms. This protein was expressed in Escherichia coli followed by its purification in a recombinant form protein exhibited a characteristic PPIases activity (Vmax = 0.8752 ± 0.13892 µmoles/min, Km = 0.9315 ± 0.5670 µM) in comparison to control. The mass spectrometry analysis of Cyp A protein-peptide showed a highest sequence similarity with the cyclophilin protein of Salmonella. PPIases proteins (enzyme) data suggest that Ppi-A has roles in the protein folding that may be contributing to the virulence of Salmonella by isomerization of protein outline. These results suggest an active and vital role of this protein in protein folding along with regulation in Salmonella Typhimurium.


Assuntos
Proteínas de Escherichia coli , Salmonella typhimurium , Animais , Proteínas da Membrana Bacteriana Externa , Ciclofilinas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Peptidilprolil Isomerase/genética , Peptidilprolil Isomerase/metabolismo , Dobramento de Proteína , Proteômica , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo
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