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1.
Microorganisms ; 10(12)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36557613

RESUMEN

New generation antibiotics are needed to combat the development of resistance to antimicrobials. One of the most promising new classes of antibiotics is cannabidiol (CBD). It is a non-toxic and low-resistance chemical that can be used to treat bacterial infections. The antibacterial activity of Cannabis sativa L. byproducts, specifically CBD, has been of growing interest in the field of novel therapeutics. As research continues to define and characterize the antibacterial activity that CBD possesses against a wide variety of bacterial species, it is important to examine potential interactions between CBD and common therapeutics such as broad-spectrum antibiotics. In this study it is demonstrated that CBD-antibiotic (combination of CBD and antibiotic) co-therapy can effectively fight Salmonella typhimurium (S. typhimurium) via membrane integrity disruption. This research serves to examine the potential synergy between CBD and three broad-spectrum antibiotics (ampicillin, kanamycin, and polymyxin B) for potential CBD-antibiotic co-therapy. In this study, it is revealed that S. typhimurium growth is inhibited at very low dosages of CBD-antibiotic. This interesting finding demonstrates that CBD and CBD-antibiotic co-therapies are viable novel alternatives to combating S. typhimurium.

2.
Arch Microbiol ; 205(1): 5, 2022 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36441284

RESUMEN

The relationship between human health and gut microbiota is becoming more apparent. It is now widely believed that healthy gut flora plays a vital role in the overall well-being of the individual. There are spatial and temporal variations in the distribution of microbes from the esophagus to the rectum throughout an individual's lifetime. Through the development of genome sequencing technologies, scientists have been able to study the interactions between different microorganisms and their hosts to improve the health and disease of individuals. The normal gut microbiota provides various functions to the host, whereas the host, in turn, provides nutrients and promotes the development of healthy and resilient microbiota communities. Thus, the microbiota provides and maintains the gut's structural integrity and protects the gut against pathogens. The development of the normal gut microbiota is influenced by various factors. Some of these include the mode of delivery, diet, and antibiotics. In addition, the environment can also affect the development of the gut microbiota. For example, one of the main concerns of antibiotic use is the alteration of the gut microbiota, which could lead to the development of multidrug-resistant organisms. When microbes are disturbed, it can potentially lead to various diseases. Depending on the species' ability to adapt to the human body's environment, the fate of the microbes in the host and their relationship with the human body are decided. This review aims to provide a comprehensive analysis of microbe, microbes-host immune interactions, and factors that can disturb their interactions.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Humanos , Nutrientes , Antibacterianos , Mapeo Cromosómico
3.
Arch Microbiol Immunol ; 6(1): 81-100, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35996377

RESUMEN

The prevalence of multidrug resistant bacterial diseases is a major global health risk. Multidrug resistant bacterial diseases are prevalent, and the need for novel methods of treatment is essential to the preservation of public health. Annually foodborne pathogens cause 1.35 million infections and 26,500 hospitalizations in the United States alone. Foodborne pathogens such as Salmonella spp. are a major threat to public health. Bacteriophages offer a unique method for the treatment of these multidrug resistant bacteria. We studied the infection dynamics of a potential mono-phage therapy of Salmonella typhimurium under various pathophysiological conditions. Furthermore, we determined the resistance dynamics of Salmonella typhimurium against P22 phage treatment. We also determined synergy with antibiotics such as ampicillin and kanamycin. This research helps to further define and show the versatility of bacteriophages as potential novel treatment methods.

4.
Molecules ; 27(9)2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35566019

RESUMEN

Products derived from Cannabis sativa L. have gained increased interest and popularity. As these products become common amongst the public, the health and potential therapeutic values associated with hemp have become a premier focus of research. While the psychoactive and medicinal properties of Cannabis products have been extensively highlighted in the literature, the antibacterial properties of cannabidiol (CBD) have not been explored in depth. This research serves to examine the antibacterial potential of CBD against Salmonella newington and S. typhimurium. In this study, we observed bacterial response to CBD exposure through biological assays, bacterial kinetics, and fluorescence microscopy. Additionally, comparative studies between CBD and ampicillin were conducted against S. typhimurium and S. newington to determine comparative efficacy. Furthermore, we observed potential resistance development of our Salmonella spp. against CBD treatment.


Asunto(s)
Cannabidiol , Cannabinoides , Cannabis , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Cannabidiol/farmacología , Cannabinoides/uso terapéutico , Extractos Vegetales/farmacología , Salmonella typhimurium
5.
Antibiotics (Basel) ; 11(5)2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35625310

RESUMEN

Salmonella typhimurium (S. typhimurium) is one of the major food and waterborne bacteria that causes several health outbreaks in the world. Although there are few antibiotics against this bacterium, some of these drugs are challenged with resistance and toxicity. To mitigate this challenge, our group explored the ethnomedicinal/herbalism knowledge about a certain spice used in Northern Ghana in West Africa against bacterial and viral infection. This plant is Capsicum chinense (C. chinense). The plant is one of the commonest food spices consumed across the world. The seed of the plant contains both capsaicin and dihydrocapsaicin. Apart from capsaicin and dihydrocapsaicin, other major capsaicinoids in C. chinense include nordihydrocapsaicin, homodihydrocapsaicin, and homocapsaicin. In this pilot work, we investigated the antibacterial activity of pure capsaicin and capsaicin extract obtained from C. chinense against S. typhimurium in vitro. Capsaicin extract showed potent inhibition of S. typhimurium growth at concentrations as low as 100 ng/mL, whereas pure capsaicin comparatively showed poorer inhibition of bacteria growth at such a concentration. Interestingly, both capsaicin extract and pure capsaicin were found to potently block a S. typhimurium invasion of the Vero cell in vitro. Taken together, we believed that capsaicin might work synergistically with dihydrocapsaicin or the other capsaicinoids to inhibit S. typhimurium growth, whereas individually, capsaicin or dihydrocapsaicin could potently block the bacteria entry and invasion of Vero cells.

6.
Arch Virol ; 163(6): 1623-1633, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29500571

RESUMEN

P22 bacteriophage has been studied extensively and has served as a model for many important processes such as in vivo protein folding, protein aggregation and protein-protein interactions. The trimeric tailspike protein (TSP) serves as the receptor-binding protein for the P22 bacteriophage to the bacterial host. The homotrimeric P22 tail consists of three chains of 666aa in which the first 108aa form a trimeric dome-like structure which is called the N-terminal domain (NTD) and is responsible for attachment of the tailspike protein to the rest of the phage particle structure in the phage assembly pathway. Knowledge of this interaction requires information on what amino acids are interacting in the interface and how the NTD structure is maintained. The first 23aa form the "stem peptide" which originates at the dome top and terminates at the dome bottom. It contains a hydrophobic valine patch (V8-V9-V10) located within the dome structure. It is hypothesized that the interaction between the hydrophobic valine patch located on stem peptide and the adjacent polypeptide is critical for the interchain interaction which should be important for the stability of the P22 TSP NTD itself. To test this hypothesis, each amino acid in the valine residues is substituted by an acid, a basic, and a hydrophobic amino acid. The results of such substitutions are presented as well as associated studies. The data strongly suggest that the valine patch is of critical importance in the hydrophobic interaction between stem peptide valine patch and an adjacent chain.


Asunto(s)
Bacteriófago P22/química , Valina/química , Proteínas de la Cola de los Virus/química , Sustitución de Aminoácidos , Bacteriófago P22/genética , Sitios de Unión , Clonación Molecular , Cristalografía por Rayos X , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Glicósido Hidrolasas , Interacciones Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Valina/metabolismo , Proteínas de la Cola de los Virus/genética , Proteínas de la Cola de los Virus/metabolismo
7.
Methods Mol Biol ; 501: 223-37, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19066824

RESUMEN

Recent studies have established that the most abundant life form, that of phages, has had major influence on the biosphere, bacterial evolution, bacterial genome, and lateral gene transmission. Importantly the phages have served and continue to serve as valuable model systems. Such studies have led to a renewed interest and activity in the study of phages and their genomes. In order to determine the details of the involvement of phages in these important processes and activities, it is critical to assign specific functions to the phage gene products. The initial functional and gene assignments can be made by general mutagenesis of the phage genomes and of these specific gene products. A very informative mutagenic protocol that has found renewed interest is that using hydroxylamine. This mutagenic protocol has been used to obtain gene mutations involved in the lysogenic cycle of the Salmonella enterica serovar Anatum var. 15+ phage epsilon34 (hereafter phage epsilon34) and to isolate conditional lethal mutants of phage epsilon34. A similar protocol using plasmid is also described. A plate complementation method is presented to determine quickly the number of genes which are present in the population of mutations isolated from hydroxylamine mutagenesis.


Asunto(s)
Bacteriófagos/genética , Mutación/genética , Prueba de Complementación Genética , Hidroxilamina/toxicidad , Mutagénesis/efectos de los fármacos , Salmonella enterica/virología
8.
BMC Microbiol ; 8: 227, 2008 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-19091116

RESUMEN

BACKGROUND: The presence of prophages has been an important variable in genetic exchange and divergence in most bacteria. This study reports the determination of the genomic sequence of Salmonella phage epsilon 34, a temperate bacteriophage that was important in the early study of prophages that modify their hosts' cell surface and is of a type (P22-like) that is common in Salmonella genomes. RESULTS: The sequence shows that epsilon 34 is a mosaically related member of the P22 branch of the lambdoid phages. Its sequence is compared with the known P22-like phages and several related but previously unanalyzed prophage sequences in reported bacterial genome sequences. CONCLUSION: These comparisons indicate that there has been little if any genetic exchange within the procapsid assembly gene cluster with P22-like E. coli/Shigella phages that are have orthologous but divergent genes in this region. Presumably this observation reflects the fact that virion assembly proteins interact intimately and divergent proteins can no longer interact. On the other hand, non-assembly genes in the "ant moron" appear to be in a state of rapid flux, and regulatory genes outside the assembly gene cluster have clearly enjoyed numerous and recent horizontal exchanges with phages outside the P22-like group. The present analysis also shows that epsilon 34 harbors a gtrABC gene cluster which should encode the enzymatic machinery to chemically modify the host O antigen polysaccharide, thus explaining its ability to alter its host's serotype. A comprehensive comparative analysis of the known phage gtrABC gene clusters shows that they are highly mobile, having been exchanged even between phage types, and that most "bacterial" gtrABC genes lie in prophages that vary from being largely intact to highly degraded. Clearly, temperate phages are very major contributors to the O-antigen serotype of their Salmonella hosts.


Asunto(s)
Genoma Viral/genética , Fagos de Salmonella/genética , Salmonella enterica/virología , Bacteriófago P22/genética , Secuencia de Bases , ADN Viral/análisis , Evolución Molecular , Fagos de Salmonella/aislamiento & purificación
9.
Virology ; 369(1): 35-46, 2007 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-17707072

RESUMEN

Macrophages are recognized cellular compartments involved in HIV infection; however, the extent to which precursor monocytes are infected in vivo and its significance remains poorly understood. Our aim was to analyze the contribution of monocytes to HIV infection in vivo. PCR assays did not detect HIV-1 proviral DNA in monocytes of HAART-suppressed patients. Monocyte-derived macrophages from individuals under suppressive HAART did not show evidence of harboring HIV, thereby, minimizing the possibility of infection by the integration of sequestered virus after differentiation. These results suggest that the infection of permissive monocytes is directly related to the success of HAART (p<0.001). HIV-1 env was characterized from patients under sub-optimal HAART and hence, with infected monocytes. Sequence analyses showed a consistent relationship between monocytes and plasma virus. Altogether, we found that in suppressive HAART, neither monocytes nor Monocyte-derived macrophages-harbored HIV.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/clasificación , Monocitos/virología , Células Cultivadas , ADN Viral/genética , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Macrófagos/virología , Datos de Secuencia Molecular , Filogenia , Plasma/virología , Reacción en Cadena de la Polimerasa , Provirus/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética
10.
Gene ; 386(1-2): 211-7, 2007 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-17113244

RESUMEN

To understand the interaction between lipopolysaccharide (LPS) and proteins in molecular detail, a molecular genetic approach has been employed, using phage as a model system. The phage epsilon(34) is a Salmonella phage whose tailspike protein (TSP) uses the host LPS as its initial host cell receptor. Previous studies indicated that there was a similarity between the well-studied tail protein of Salmonella phage P22 and the epsilon(34). This study reports the identification of the gene for the epsilon(34) TSP as well as its initial characterization. In addition, some aspects of the structure of the epsilon(34) TSP have been deduced.


Asunto(s)
Fagos de Salmonella/genética , Proteínas de la Cola de los Virus/genética , Secuencia de Aminoácidos , Secuencia de Bases , Datos de Secuencia Molecular , Salmonella enterica/genética , Salmonella enterica/virología
11.
P R Health Sci J ; 23(2): 95-101, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15377056

RESUMEN

OBJECTIVES: The goals of these studies were to characterize the interaction of the P22 phage particle with the Salmonella cell surface and to determine the phage elements involved in this interaction by mutational analysis. BACKGROUND: The phage P22 has been characterized extensively. The gene and protein for the phage P22 tailspike, which is the phage adsorption organelle, have been intensively studied. The kinetics of the interaction of the tailspike protein with the cell surface has been studied in detail, surprisingly no mutational analysis has ever been reported that has defined these components and their interaction between themselves and the cell surface. The main and perhaps only component needed for this cell surface interaction is the tailspike protein. METHODS: Adsorption to the cell surface has been measured in the wild type phage and in mutant derivatives, isolated in this study. Phage mutants have been isolated after hydroxylamine mutagenesis. RESULTS: The adsorption of P22 to the cell surface is a temperature-independent event. Forty putative phage adsorption mutants have been isolated. A sample of them have been further analyzed. These divide the adsorption process into at least two stages. One stage contains mutants that absorb with essential wild type phage kinetics to the cell surface while the other stage with delayed adsorption kinetics. CONCLUSIONS: The interaction of the phage P22 with the Salmonella cell surface has been shown to be a complicated one which is temperature-independent and multi-stage. Mutants isolated in this study may help dissect this process even further.


Asunto(s)
Adsorción , Bacteriófago P22/metabolismo , Salmonella typhimurium/virología , Bacteriófago P22/ultraestructura , Humanos , Lipopolisacáridos/metabolismo , Salmonella typhimurium/metabolismo , Salmonella typhimurium/ultraestructura , Temperatura , Proteínas de la Cola de los Virus/metabolismo
12.
Virus Genes ; 29(1): 87-98, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15215687

RESUMEN

A distinguishing feature of many microorganisms, belonging to the Gram negative group of bacteria, is the presence of the lipopolysaccharide on their cell surface. Salmonella is a prominent member of this group of bacteria. Many Salmonella phages use the LPS as the initial receptor in the infection process and they can distinguish subtle changes in the LPS molecules. The phage protein that is responsible for recognition of these cells is the tail or tailspike protein (TSP). Those TSPs, which use LPS as a receptor, are prokaryotic LPS-binding proteins. As an initial step in using phage TSPs as model systems for a detailed molecular genetic analysis of protein-LPS interactions, a comparison of two phages and their TSPs from two different Salmonella bacterial viruses (phages), Salmonella enterica serovar Typhimurium phage P22 and Salmonella enterica serovar Anatum var. 15 + phage epsilon34, is being carried out. This present study shows significant viral protein homology between many viral structural proteins from these two phages including their TSPs. Significantly this report suggests a general structural motif for part of the TSP of phages and suggests that a more detailed comparative analysis of these TSPs is warranted.


Asunto(s)
Bacteriófago P22/genética , Fagos de Salmonella/genética , Salmonella enterica/virología , Salmonella typhimurium/virología , Animales , Bacteriófago P22/metabolismo , Tipificación de Bacteriófagos , Evolución Molecular , Glicósido Hidrolasas , Lipopolisacáridos/metabolismo , Ratones , Salmonelosis Animal/virología , Fagos de Salmonella/metabolismo , Proteínas Estructurales Virales/genética , Proteínas Estructurales Virales/metabolismo , Proteínas de la Cola de los Virus/genética , Proteínas de la Cola de los Virus/metabolismo
13.
P. R. health sci. j ; P. R. health sci. j;18(4): 363-7, dez. 1999. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-260829

RESUMEN

This brief report describes the isolation and initial characterization of revertants to the most severe temperature sensitive folding mutant known. The revertants or suppressors may describe amino acid interactions that occur during the folding of the P22 tailspike polypeptide chain. Results indicate that several different types of suppressors may have been obtained.


Asunto(s)
/genética , Genes Supresores/genética , Glicósido Hidrolasas/genética , Mutación , Pliegue de Proteína , Proteínas de la Cola de los Virus/genética
14.
P. R. health sci. j ; P. R. health sci. j;18(2): 105-15, jun. 1999. ilus, tab
Artículo en Inglés | LILACS | ID: lil-255644

RESUMEN

This review describes the use of a simple genetic system that has provided important insight into the process of folding and, of its flipside, that of protein aggregation. These studies make use of the tail protein of the bacterial virus P22 which infects Salmonella typhimurium. This folding system serves as a model for a number protein structural elements and may also provide important insights into disease-related protein folding defects at a time when an increasing number of diseases are being shown to be due to protein folding alterations


Asunto(s)
Humanos , /genética , Técnicas In Vitro , Pliegue de Proteína , Proteínas de la Cola de los Virus/genética , Aminoácidos/genética , Aminoácidos/metabolismo , /fisiología , ADN Viral/genética , Hidrólisis , Mutación , Conformación Proteica , Salmonella typhimurium/virología
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