Characterization of a Putative Pathogenicity Island from Bovine Staphylococcus aureus Encoding Multiple Superantigens

ABSTRACT Previous studies have demonstrated that a proportion ofStaphylococcus aureus isolates from bovine mastitis coproduce toxic shock syndrome toxin (TSST) and staphylococcal enterotoxin C (SEC). In this study, molecular genetic analysis of one such strain, RF122, revealed the presence of a 15,891-bp putative pathogenicity island (SaPIbov) encoding the genes for TSST (tst), the SEC bovine variant (sec-bovine), and a gene (sel) which encodes an enterotoxin-like protein. The island contains 21 open reading frames specifying hypothetical proteins longer than 60 amino acids including an integrase-like gene. The element is bordered by 74-bp direct repeats at the left and right junctions, and the integration site lies adjacent to the 3′ end of the GMP synthase gene (gmps) in the S. aureuschromosome. SaPIbov contains a central region of sequence identity with the previously characterized tst pathogenicity island SaPI1 (J. A. Lindsay et al., Mol. Microbiol. 29:527–543, 1998). A closely related strain, RF120, of the same multilocus enzyme electrophoretic type, random amplified polymorphic DNA type, and ribotype, does not contain the island, implying that the element is mobile and that a recent insertion/deletion event has taken place. TSST and TSST/SEC-deficient mutants of S. aureus strain RF122 were constructed by allele replacement. In vitro bovine Vβ-specific lymphocyte expansion analysis by culture supernatants of wild-type strains and of tst and sec-bovine allele replacement mutants revealed that TSST stimulates BTB13-specific T cells whereas SEC-bovine stimulates BTB93-specific T cells. This suggests that the presence of SaPIbov may contribute to modulation of the bovine immune response.

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Molecular Characterization and Genetic Diversity Study in F3 Population of Rice

Progressive Agriculture ◽

10.3329/pa.v20i1-2.16839 ◽

2013 ◽

Vol 20 (1-2) ◽

pp. 1-8

Author(s):

MM Rahman ◽

L Rahman ◽

SN Begum ◽

F Nur

Keyword(s):

Genetic Distance ◽

Gene Diversity ◽

Random Amplified Polymorphic Dna ◽

Molecular Genetic ◽

Molecular Genetic Analysis ◽

Polymorphic Loci ◽

Rice Genotypes ◽

High Level ◽

Genetic Diversity Study ◽

Diversity Study

Random Amplified Polymorphic DNA (RAPD) assay was initiated for molecular genetic analysis among 13 F3 rice lines and their parents. Four out of 15 decamer random primers were used to amplify genomic DNA and the primers yielded a total of 41 RAPD markers of which 37 were considered as polymorphic with a mean of 9.25 bands per primer. The percentage of polymorphic loci was 90.24. The highest percentage of polymorphic loci (14.63) and gene diversity (0.0714) was observed in 05-6 F3 line and the lowest polymorphic loci (0.00) and gene diversity (0.00) was found in 05-12 and 05-15 F3 lines. So, relatively high level of genetic variation was found in 05-6 F3 line and it was genetically more diverse compared to others. The average co-efficient of gene differentiation (GST) and gene flow (Nm) values across all the loci were 0.8689 and 0.0755, respectively. The UPGMA dendrogram based on the Neis genetic distance differentiated the rice genotypes into two main clusters: PNR-519, 05-19, 05-14, 05-12 and 05-17 grouped in cluster 1. On the other hand, Baradhan, 05-9, 05-13, 05-11, 05-5, 05-6, 05-1, 05-4, 05-15 and 05-25 were grouped in cluster 2. The highest genetic distance (0.586) was found between 05-4 and 05-17 F3 lines and they remain in different cluster.DOI: http://dx.doi.org/10.3329/pa.v20i1-2.16839 Progress. Agric. 20(1 & 2): 1 8, 2009

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Molecular Genetic Analysis of Nucleotide Polymorphisms Associated with Ethambutol Resistance in Human Isolates ofMycobacterium tuberculosis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.2.326-336.2000 ◽

2000 ◽

Vol 44 (2) ◽

pp. 326-336 ◽

Cited By ~ 154

Author(s):

Srinivas V. Ramaswamy ◽

Amol G. Amin ◽

Servet Göksel ◽

Charles E. Stager ◽

Shu-Jun Dou ◽

...

Keyword(s):

Amino Acid ◽

Single Gene ◽

Molecular Genetic ◽

Regulatory Region ◽

Amino Acid Replacement ◽

Molecular Genetic Analysis ◽

Central Component ◽

Nucleotide Polymorphisms ◽

Molecular Change

ABSTRACT Ethambutol (EMB) is a central component of drug regimens used worldwide for the treatment of tuberculosis. To gain insight into the molecular genetic basis of EMB resistance, approximately 2 Mb of five chromosomal regions with 12 genes in 75 epidemiologically unassociated EMB-resistant and 33 EMB-susceptible Mycobacterium tuberculosis strains isolated from human patients were sequenced. Seventy-six percent of EMB-resistant organisms had an amino acid replacement or other molecular change not found in EMB-susceptible strains. Thirty-eight (51%) EMB-resistant isolates had a resistance-associated mutation in only 1 of the 12 genes sequenced. Nineteen EMB-resistant isolates had resistance-associated nucleotide changes that conferred amino acid replacements or upstream potential regulatory region mutations in two or more genes. Most isolates (68%) with resistance-associated mutations in a single gene had nucleotide changes in embB, a gene encoding an arabinosyltransferase involved in cell wall biosynthesis. The majority of these mutations resulted in amino acid replacements at position 306 or 406 of EmbB. Resistance-associated mutations were also identified in several genes recently shown to be upregulated in response to exposure of M. tuberculosis to EMB in vitro, including genes in theiniA operon. Approximately one-fourth of the organisms studied lacked mutations inferred to participate in EMB resistance, a result indicating that one or more genes that mediate resistance to this drug remain to be discovered. Taken together, the results indicate that there are multiple molecular pathways to the EMB resistance phenotype.

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In Vitro Analysis of Predicted DNA-Binding Sites for the Stl Repressor of the Staphylococcus aureus SaPIBov1 Pathogenicity Island

PLoS ONE ◽

10.1371/journal.pone.0158793 ◽

2016 ◽

Vol 11 (7) ◽

pp. e0158793 ◽

Cited By ~ 7

Author(s):

Veronika Papp-Kádár ◽

Judit Eszter Szabó ◽

Kinga Nyíri ◽

Beata G. Vertessy

Keyword(s):

Staphylococcus Aureus ◽

Dna Binding ◽

Binding Sites ◽

Pathogenicity Island ◽

Dna Binding Sites ◽

Vitro Analysis ◽

In Vitro Analysis

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Loss of Parkin impairs mitochondrial function and leads to muscle atrophy

AJP Cell Physiology ◽

10.1152/ajpcell.00064.2017 ◽

2018 ◽

Vol 315 (2) ◽

pp. C164-C185 ◽

Cited By ~ 15

Author(s):

Nesibe Peker ◽

Vinay Donipadi ◽

Mridula Sharma ◽

Craig McFarlane ◽

Ravi Kambadur

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Mitochondrial Function ◽

Molecular Genetic ◽

Muscle Growth ◽

Molecular Genetic Analysis ◽

Muscle Stiffness ◽

C2c12 Cells ◽

Mitochondrial Uncoupler

Parkinson’s disease is a neurodegenerative disease characterized by tremors, muscle stiffness, and muscle weakness. Molecular genetic analysis has confirmed that mutations in PARKIN and PINK1 genes, which play major roles in mitochondrial quality control and mitophagy, are frequently associated with Parkinson’s disease. PARKIN is an E3 ubiquitin ligase that translocates to mitochondria during loss of mitochondrial membrane potential to increase mitophagy. Although muscle dysfunction is noted in Parkinson’s disease, little is known about the involvement of PARKIN in the muscle phenotype of Parkinson’s disease. In this study, we report that the mitochondrial uncoupler CCCP promotes PINK1/PARKIN-mediated mitophagy in myogenic C2C12 cells. As a result of this excess mitophagy, we show that CCCP treatment of myotubes leads to the development of myotube atrophy in vitro. Surprisingly, we also found that siRNA-mediated knockdown of Parkin results in impaired mitochondrial turnover. In addition, knockdown of Parkin led to myotubular atrophy in vitro. Consistent with these in vitro results, Parkin knockout muscles showed impaired mitochondrial function and smaller myofiber area, suggesting that Parkin function is required for post-natal skeletal muscle growth and development.

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Variation in Septoria musiva and Implications for Disease Resistance Screening of Poplars

Plant Disease ◽

10.1094/pd-89-1077 ◽

2005 ◽

Vol 89 (10) ◽

pp. 1077-1082 ◽

Cited By ~ 12

Author(s):

K. T. Ward ◽

M. E. Ostry

Keyword(s):

Disease Resistance ◽

Random Amplified Polymorphic Dna ◽

Molecular Genetic ◽

Hybrid Poplar ◽

Field Resistance ◽

Leaf Disk ◽

Resistance Screening ◽

Septoria Musiva ◽

Disease Resistance Screening

A set of isolates of Septoria musiva differed in aggressiveness in hybrid poplar leaf disk and stem assays and culture growth in vitro. Clone × isolate interactions were observed in one of the stem assay experiments, but not in the leaf disk assay experiments. Random amplified polymorphic DNA (RAPD) analyses were performed using 52 isolates of S. musiva collected from hybrid poplars and a native poplar species in Minnesota, Wisconsin, Iowa, South Dakota, and North Dakota. There was a large degree of genetic similarity, although each isolate had a unique RAPD pattern. No relationships among isolates were found for molecular genetic distance and host clone, parentage, or taxonomic classification section; location or date of collection; or the previously determined level of field resistance of the host clones to Septoria canker. Results of the stem and leaf disk assays indicate that it may not be necessary to choose the most aggressive isolate for disease resistance screening. It may be more useful to select isolates that will discriminate the greatest variation in levels of disease resistance among the clones that are being screened.

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Induction of Cell-Mediated Immunity to Staphylococcus aureus in the Mouse Mammary Gland by Local Immunization with a Live Attenuated Mutant

Infection and Immunity ◽

10.1128/iai.70.8.4254-4260.2002 ◽

2002 ◽

Vol 70 (8) ◽

pp. 4254-4260 ◽

Cited By ~ 20

Author(s):

Marisa I. Gómez ◽

Daniel O. Sordelli ◽

Fernanda R. Buzzola ◽

Verónica E. García

Keyword(s):

Staphylococcus Aureus ◽

T Cells ◽

Mammary Gland ◽

Mononuclear Cells ◽

Regional Lymph Node ◽

Interleukin 2 ◽

Mouse Mammary Gland ◽

Cell Mediated Immunity ◽

Ifn Γ

ABSTRACT The efficacy of intramammary (Ima) immunization with a live attenuated (la) Staphylococcus aureus mutant to protect the mouse mammary gland from infection has previously been established. The present study was aimed at evaluating whether Ima immunization with la-S. aureus can induce cell-mediated immune responses to the pathogen within the mammary gland. Mice were immunized by Ima route with la-S. aureus, and regional lymph node mononuclear cells were obtained thereafter. A higher expression of the interleukin-2 receptor was found on B and T cells from immunized mice when they were compared with control mice. Immunization with la-S. aureus induced strong proliferative responses to S. aureus. Moreover, significantly increased levels of gamma interferon (IFN-γ) were produced by CD4+ T cells when lymphocytes from immunized mice, but not from control mice, were cultured in the presence of staphylococcal antigens. Moreover, a significant increase in the percentage of IFN-γ-producing CD4+ and CD8+ T cells was observed after S. aureus Ima challenge in immunized mice compared to challenged control mice. Our results demonstrated that Ima immunization with la-S. aureus induced primed lymphocyte populations capable of responding against staphylococcal antigens during in vitro stimulation, as well as during in vivo infection by S. aureus. CD4+ and CD8+ T cells appear to be the main lymphocyte subpopulations involved in this response. It is suggested that IFN-γ production induced by Ima immunization may play a pivotal role in the eradication of intracellular staphylococci.

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Molecular Genetic and Structural Modeling Studies of Staphylococcus aureus RNA Polymerase and the Fitness of Rifampin Resistance Genotypes in Relation to Clinical Prevalence

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.50.1.298-309.2006 ◽

2006 ◽

Vol 50 (1) ◽

pp. 298-309 ◽

Cited By ~ 74

Author(s):

A. J. O'Neill ◽

T. Huovinen ◽

C. W. G. Fishwick ◽

I. Chopra

Keyword(s):

Staphylococcus Aureus ◽

Rna Polymerase ◽

Molecular Genetic ◽

Fitness Costs ◽

Novel Mutations ◽

Resistant Strains ◽

Rifampin Resistance ◽

First Time ◽

Selection Of

ABSTRACT The adaptive and further evolutionary responses of Staphylococcus aureus to selection pressure with the antibiotic rifampin have not been explored in detail. We now present a detailed analysis of these systems. The use of rifampin for the chemotherapy of infections caused by S. aureus has resulted in the selection of mutants with alterations within the β subunit of the target enzyme, RNA polymerase. Using a new collection of strains, we have identified numerous novel mutations in the β subunits of both clinical and in vitro-derived resistant strains and established that additional, undefined mechanisms contribute to expression of rifampin resistance in clinical isolates of S. aureus. The fitness costs associated with rifampin resistance genotypes were found to have a significant influence on their clinical prevalence, with the most common clinical genotype (H481N, S529L) exhibiting no fitness cost in vitro. Intragenic mutations which compensate for the fitness costs associated with rifampin resistance in clinical strains of S. aureus were identified for the first time. Structural explanations for rifampin resistance and the loss of fitness were obtained by molecular modeling of mutated RNA polymerase enzymes.

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Deletions within the HSV-tk transgene in long-lasting circulating gene-modified T cells infused with a hematopoietic graft

Blood ◽

10.1182/blood-2007-04-087346 ◽

2007 ◽

Vol 110 (12) ◽

pp. 3842-3852 ◽

Cited By ~ 19

Author(s):

Marina Deschamps ◽

Patricia Mercier-Lethondal ◽

Jean Marie Certoux ◽

Carole Henry ◽

Bruno Lioure ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Phase 1 ◽

Patient Specific ◽

Deletion Event ◽

In Vitro Expansion ◽

Ganciclovir Treatment ◽

Simplex Virus

AbstractIn our previous phase 1/2 study aimed at controlling graft-versus-host disease, 12 patients received Herpes simplex virus thymidine kinase (HSV-tk+)/neomycin phosphotransferase (NeoR+)–expressing donor gene-modified T cells (GMCs) and underwent an HLA-identical sibling T-cell–depleted bone marrow transplantation (BMT). This study's objective was to follow up, to quantify, and to characterize persistently circulating GMCs more than 10 years after BMT. Circulating GMCs remain detectable in all 4 evaluable patients. However, NeoR- and HSV-tk–polymerase chain reaction (PCR) differently quantified in vivo counts, suggesting deletions within the HSV-tk gene. Further experiments, including a novel “transgene walking” PCR method, confirmed the presence of deletions. The deletions were unique, patient-specific, present in most circulating GMCs expressing NeoR, and shown to occur at time of GMC production. Unique patient-specific retroviral insertion sites (ISs) were found in all GMCs capable of in vitro expansion/cloning as well. These findings suggest a rare initial gene deletion event and an in vivo survival advantage of rare GMC clones resulting from an anti–HSV-tk immune response and/or ganciclovir treatment. In conclusion, we show that donor mature T cells infused with a T-cell–depleted graft persist in vivo for more than a decade. These cells, containing transgene deletions and subjected to significant in vivo selection, represent a small fraction of T cells infused at transplantation.

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Study of Phytophthora infestans Mont. de Bary isolates in the planting of potatoes

VEGETABLE CROPS OF RUSSIA ◽

10.18619/2072-9146-2021-6-86-91 ◽

2021 ◽

pp. 86-91

Author(s):

N. V. Matsishina ◽

P. V. Fisenko ◽

O. A. Sobko ◽

I. V. Kim ◽

D. I. Volkov ◽

...

Keyword(s):

Phytophthora Infestans ◽

Molecular Genetic ◽

Microscopic Analysis ◽

Molecular Genetic Analysis ◽

In Vitro Cultivation ◽

Genetic Characteristics ◽

Potato Varieties ◽

Phytotoxic Activity ◽

Wide Range

Relevance. One of the most common diseases of potatoes and other nightshade family species is late blight caused by a pathogenic oomycete of the Phytophthora infestans (Mont.) de Bary. At least 100 species of phytophthora have been described in nature, affecting a wide range of plant species. The phytophthora population is heterogeneous and is represented by races, as well as different types of mating. This leads to a rapid adaptation of the pathogen and the emergence of new, more aggressive, and resistant races. Phytophthora is a parasite, the damage from which cannot be avoided within the organic farming framework. Therefore, it is particularly important to know the pathogenesis and racial composition of phytophthora in each individual region of Solanaceae cultivation.Research methodology. Differentiation and collection of material from the natural population were carried out using potato varieties with known R-genes in the genome. Isolation and introduction into the culture were carried out from leaves with the dampening chambers method, followed by cultivation on nutrient media. The pathogen was identified by microscopic analysis. Culture filtrates were obtained on the liquid nutritious medium, followed by liquid filtration and autoclaving. Phytotoxic activity was determined by the effect on the seedlings of the nightshade, grass, and pea families by the standard method. Molecular genetic analysis of the isolates was carried out by ISSR analysis; the primer, amplification mixture, and temperature profile of the reaction were selected according to the literature data; the calculation of genetic characteristics was carried out using POPGENE software packages.Results. Samples of seven Phytophthora infestans isolates were collected and introduced into culture. As a result of in vitro cultivation, morphological differences were revealed, expressed in the structure and color of the mycelium, the shape of the colonies, the nature of sporulation, the color of the reverse, and the medium under the colonies. The genetic differences of the natural phytophthora material introduced into the culture, collected from potato varieties with single resistance genes (R1, R3, R4), were revealed. Differences in the phytotoxic activity of the studied isolates' cultural filtrates were revealed. The isolated isolates demonstrate differentiation at the phenotypic, genetic and physiological levels, which allows us to speak about their belonging to races.

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Molecular Genetic Analysis Of C-X-C Motif Chemokine Ligand 9 (CXCL9) As A Novel Biomarker In Atherosclerosis

The American Journal of Applied Sciences ◽

10.37547/tajas/volume03issue05-05 ◽

2021 ◽

Vol 3 (05) ◽

pp. 24-30

Author(s):

Dilbar T. Mirzarakhmetova ◽

◽

Yulduz Yusupbaevna Baltaeva ◽

Keyword(s):

Adaptive Immunity ◽

Molecular Genetic ◽

Gene Signature ◽

Molecular Genetic Analysis ◽

Blood Leukocytes ◽

Innate And Adaptive Immunity ◽

Chemokine Ligand ◽

Ifn Γ ◽

Artery Disease

For almost a century, many have considered lipids as the sine qua non of atherosclerosis. However, in 1856 Rudolf Virchow introduced a theory that inflammation is the driving force of atherogenesis. Recruitment of blood leukocytes to the injured vascular endothelium characterizes the initiation and progression of atherosclerosis and involves many inflammatory mediators, modulated by cells of both innate and adaptive immunity. The pro-inflammatory cytokine, interferon (IFN)-γ derived from T cells, is vital for both innate and adaptive immunity and is also expressed at high levels in atherosclerotic lesions. As such, IFN-γ plays a crucial role in the pathology of atherosclerosis through activation of signal transducer and activator of transcription STAT1.Our study indeed provides evidence that in HMECs STAT1 coordinates a platform for cross-talk between IFNγ and TLR4, and identifies a STAT1-dependent gene signature that reflects a pro-atherogenic state in coronary artery disease (CAD) and carotid atherosclerosis. Taken together, our data indicate that in the presence of appropriate stimuli, HMECs are highly responsive and consistently express Cxcl9. HMECs may therefore provide a better model for in vitro studies of atherosclerosis.

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