Uses of Staphylococcus aureus GeneChips in Genotyping and Genetic Composition Analysis

Orbignya speciosa (babassu) is an important palm tree in Brazil whose fixed almond oil is used in popular medicine and especially in food, in addition to being a research target for the manufacture of biofuels. The aim of this study was to evaluate the fixed almond oil physicochemical characterization and its antibacterial activity in isolation and in association with aminoglycosides against standard and multidrug-resistant bacteria. Analyses such as water content, pH, acidity, peroxide index, relative density, and refractive index indicate the stability and chemical quality of the oil. In the oil’s GC/MS chemical composition analysis, a high saturated fatty acid (76.90%) content was observed. Lauric acid (56.28%) and oleic acid (23.10%) were the major oil components. In the antibacterial test, a more significant oil activity was observed against K. pneumoniae KP-ATCC 10031 (minimal inhibitory concentration (MIC) = 406.37 μg/mL) and Staphylococcus aureus ATCC 6538 (MIC = 812.75 μg/mL), but for the other strains—including standard and multi-resistant strains—the oil presented an MIC ≥ 1024 μg/mL. Furthermore, a synergistic effect was observed when the oil was associated with amikacin and gentamicin against S. aureus (SA-10) and an antagonistic effect was observed with amikacin against Escherichia coli. Data indicate the O. speciosa oil as a valuable nutritional source of lauric, oleic, and myristic fatty acids with an ability to modulate aminoglycoside activity.

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Inhibition of Staphylococcus aureus Cell Wall Biosynthesis by Desleucyl-Oritavancin: a Quantitative Peptidoglycan Composition Analysis by Mass Spectrometry

Journal of Bacteriology ◽

10.1128/jb.00278-17 ◽

2017 ◽

Vol 199 (15) ◽

Cited By ~ 6

Author(s):

James D. Chang ◽

Erin E. Foster ◽

Aanchal N. Thadani ◽

Alejandro J. Ramirez ◽

Sung Joon Kim

Keyword(s):

Mass Spectrometry ◽

Staphylococcus Aureus ◽

Cell Wall ◽

Binding Site ◽

Mode Of Action ◽

Composition Analysis ◽

Edman Degradation ◽

Glycopeptide Antibiotics ◽

Content Type ◽

The Cross

ABSTRACT Oritavancin is a lipoglycopeptide antibiotic that exhibits potent activities against vancomycin-resistant Gram-positive pathogens. Oritavancin differs from vancomycin by a hydrophobic side chain attached to the drug disaccharide, which forms a secondary binding site to enable oritavancin binding to the cross-linked peptidoglycan in the cell wall. The mode of action of secondary binding site was investigated by measuring the changes in the peptidoglycan composition of Staphylococcus aureus grown in the presence of desleucyl-oritavancin at subinhibitory concentration using liquid chromatography-mass spectrometry (LC-MS). Desleucyl-oritavancin is an Edman degradation product of oritavancin that exhibits potent antibacterial activities despite the damaged d-Ala–d-Ala binding site due to its functional secondary binding site. Accurate quantitative peptidoglycan composition analysis based on 83 muropeptide ions determined that cell walls of S. aureus grown in the presence of desleucyl-oritavancin showed a reduction of peptidoglycan cross-linking, increased muropeptides with a tetrapeptide-stem structure, decreased O-acetylation of MurNAc, and increased N-deacetylation of GlcNAc. The changes in peptidoglycan composition suggest that desleucyl-oritavancin targets the peptidoglycan template to induce cell wall disorder and interferes with cell wall maturation. IMPORTANCE Oritavancin is a lipoglycopeptide antibiotic with a secondary binding site that targets the cross-linked peptidoglycan bridge structure in the cell wall. Even after the loss of its primary d-Ala–d-Ala binding site through Edman degradation, desleucyl-oritavancin exhibits potent antimicrobial activities through its still-functioning secondary binding site. In this study, we characterized the mode of action for desleucyl-oritavancin's secondary binding site using LC-MS. Peptidoglycan composition analysis of desleucyl-oritavancin-treated S. aureus was performed by determining the relative abundances of 83 muropeptide ions matched from a precalculated library through integrating extracted ion chromatograms. Our work highlights the use of quantitative peptidoglycan composition analysis by LC-MS to provide insights into the mode of action of glycopeptide antibiotics.

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Microbiological and Proximate Analyses of Lebanese Bread (Pita) from Akure Metropolis

South Asian Journal of Research in Microbiology ◽

10.9734/sajrm/2019/v3i130079 ◽

2019 ◽

pp. 1-11

Author(s):

Christiana E. Aruwa ◽

Ayobami R. Farotimi

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Proximate Composition ◽

Micrococcus Luteus ◽

Bacterial Count ◽

Composition Analysis ◽

Industrial Chemistry ◽

Microbiological Techniques ◽

Zones Of Inhibition ◽

Pita Bread

Aim: This study aimed at evaluating the microbial quality and proximate composition of pita samples from Akure metropolis. Place and Duration of Study: Microbiology and Industrial Chemistry laboratories of the Federal University of Technology, Akure (FUTA), Ondo State, Nigeria, between January 2016 and June 2016. Methodology: Pita samples were evaluated using standard microbiological techniques to ascertain microbial load and types after purchase from vendors utilizing them alone or in production of other foods. Antibiotic susceptibility profile of isolates was also determined. Proximate composition analysis of samples was also performed. Results: Average bacterial count was 1.0±0.9 cfu/g, while average fungal count was 2.0±1.2 sfu/g. The fungi isolated were Rhizopus stolonifer, Saccharomyces cerevisiae and Aspergillus niger; while the bacteria isolated were Bacillus cereus, Staphylococcus sp., Micrococcus luteus, Pseudomonas aeruginosa, and Proteus vulgaris. Microbial zones of inhibition ranged from 17 mm to 23.50 mm. Micrococcus luteus, Staphylococcus aureus and Pseudomonas aeruginosa were most susceptible to gentamycin, pefloxacin and amoxycillin, respectively. Staphylococcus aureus showed the widest antimicrobial resistant pattern. The highest carbohydrate content was recorded as 78.99 %, while bread samples showed low ash content (0.65 %). Conclusion: Pita bread is not a common staple compared to leavened breads but provides appreciable level of nutrients. Pita bread requires regular microbial assessment to determine their safety for direct consumption or use in production of other food products.

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Bovine milk somatic cell transcriptomic response to Staphylococcus aureus is dependent on strain genotype

10.1101/2021.03.04.433893 ◽

2021 ◽

Author(s):

Dagmara Niedziela ◽

Paul Cormican ◽

Gilles Foucras ◽

Finola Leonard ◽

Orla Keane

Keyword(s):

Staphylococcus Aureus ◽

Immune Response ◽

Somatic Cell ◽

Post Infection ◽

Molecular Mechanisms ◽

Clinical Signs ◽

Differentially Expressed ◽

Composition Analysis ◽

Transcriptomic Response ◽

M1 Macrophages

AbstractBackgroundMastitis is an economically important disease of dairy cows with Staphylococcus aureus a major cause worldwide. Challenge of Holstein-Friesian cows demonstrated that a strain belonging to Clonal Complex (CC)151 caused clinical mastitis, while a strain belonging to CC97 caused mild or subclinical mastitis. The aim of this study was to elucidate the molecular mechanisms of the host immune response utilising a transcriptomic approach. Milk somatic cells from cows infected with each strain of S. aureus at 0, 24, 48, 72 and 168 hours post-infection (hpi) were analysed for differentially expressed (DE) genes in response to each strain.ResultsIn response to MOK023 (CC97), 1278, 2278, 1986 and 1750 significant differentially expressed (DE) genes were found at 24, 48, 72 and 168 hpi, respectively, while 2293, 1979, 1428 and 1544 significant DE genes were found in response to MOK124 (CC151) at those time points. Genes involved in milk production (CSN1, CSN10, CSN1S2, CSN2, a-LACTA and PRLR) were downregulated in response to both strains, with a more pronounced decrease in the MOK124 group. Immune response pathways such as NF-κB and TNF signalling were overrepresented in response to both strains at 24 hpi. These immune pathways continued to be overrepresented in the MOK023 group at 48 and 72 hpi, while the Hippo signalling, extracellular matrix interaction (ECM) and tight junction pathways were overrepresented in the MOK124 group between 48 and 168 hpi. Cellular composition analysis demonstrated that a neutrophil response was predominant in response to MOK124, while M1 macrophages were the main milk cell type post-infection in the MOK023 group.ConclusionsA switch from immune response pathways to pathways involved in maintaining the integrity of the epithelial cell layer was observed in the MOK124 group from 48 hpi, which coincided with the occurrence of clinical signs in the infected animals. The higher proportion of M1 macrophages in the MOK023 group and lack of substantial neutrophil recruitment in response to MOK023 may indicate immune evasion by this strain. The results of this study highlight that the somatic cell transcriptomic response to S. aureus is dependent on the genotype of the infecting strain.

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X-chromosomal STRs for genetic composition analysis of Guizhou Dong group and its phylogenetic relationships with other reference populations

Annals of Human Biology ◽

10.1080/03014460.2021.2008001 ◽

2021 ◽

pp. 1-9

Author(s):

Meiqing Yang ◽

Xiaoye Jin ◽

Zheng Ren ◽

Qiyan Wang ◽

Hongling Zhang ◽

...

Keyword(s):

Phylogenetic Relationships ◽

Composition Analysis ◽

Genetic Composition

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Bovine milk somatic cell transcriptomic response to Staphylococcus aureus is dependent on strain genotype

BMC Genomics ◽

10.1186/s12864-021-08135-7 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Dagmara A. Niedziela ◽

Paul Cormican ◽

Gilles Foucras ◽

Finola C. Leonard ◽

Orla M. Keane

Keyword(s):

Staphylococcus Aureus ◽

Immune Response ◽

Somatic Cell ◽

Post Infection ◽

Molecular Mechanisms ◽

Bovine Milk ◽

Clinical Signs ◽

Composition Analysis ◽

Transcriptomic Response ◽

M1 Macrophages

Abstract Background Mastitis is an economically important disease of dairy cows with Staphylococcus aureus a major cause worldwide. Challenge of Holstein-Friesian cows demonstrated that S. aureus strain MOK124, which belongs to Clonal Complex (CC)151, caused clinical mastitis, while strain MOK023, belonging to CC97, caused mild or subclinical mastitis. The aim of this study was to elucidate the molecular mechanisms of the host immune response utilising a transcriptomic approach. Milk somatic cells were collected from cows infected with either S. aureus MOK023 or MOK124 at 0, 24, 48, 72 and 168 h post-infection (hpi) and analysed for differentially expressed (DE) genes in response to each strain. Results In response to MOK023, 1278, 2278, 1986 and 1750 DE genes were found at 24, 48, 72 and 168 hpi, respectively, while 2293, 1979, 1428 and 1544 DE genes were found in response to MOK124 at those time points. Genes involved in milk production (CSN1, CSN10, CSN1S2, CSN2, a-LACTA and PRLR) were downregulated in response to both strains, with a more pronounced decrease in the MOK124 group. Immune response pathways such as NF-κB and TNF signalling were overrepresented in response to both strains at 24 hpi. These immune pathways continued to be overrepresented in the MOK023 group at 48 and 72 hpi, while the Hippo signalling, extracellular matrix interaction (ECM) and tight junction pathways were overrepresented in the MOK124 group between 48 and 168 hpi. Cellular composition analysis demonstrated that a neutrophil response was predominant in response to MOK124, while M1 macrophages were the main milk cell type post-infection in the MOK023 group. Conclusions A switch from immune response pathways to pathways involved in maintaining the integrity of the epithelial cell layer was observed in the MOK124 group from 48 hpi, which coincided with the occurrence of clinical signs in the infected animals. The higher proportion of M1 macrophages in the MOK023 group and lack of substantial neutrophil recruitment in response to MOK023 may indicate immune evasion by this strain. The results of this study highlight that the somatic cell transcriptomic response to S. aureus is dependent on the genotype of the infecting strain.

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Modulation of the Antibiotic Activity by the Mauritia flexuosa (Buriti) Fixed Oil against Methicillin-Resistant Staphylococcus Aureus (MRSA) and Other Multidrug-Resistant (MDR) Bacterial Strains

Pathogens ◽

10.3390/pathogens7040098 ◽

2018 ◽

Vol 7 (4) ◽

pp. 98 ◽

Cited By ~ 6

Author(s):

Yara Faustino Pereira ◽

Maria do Socorro Costa ◽

Saulo Relison Tintino ◽

Janaína Esmeraldo Rocha ◽

Fábio Fernandes Galvão Rodrigues ◽

...

Keyword(s):

Fatty Acids ◽

Staphylococcus Aureus ◽

Oleic Acid ◽

Unsaturated Fatty Acids ◽

Saturated Fatty Acids ◽

Physicochemical Characterization ◽

Composition Analysis ◽

Palm Tree ◽

Bacterial Strains ◽

Mauritia Flexuosa

Mauritia flexuosa (buriti) is a typical Brazilian palm tree found in swampy regions with many plant forms. The fruit has various purposes with the pulps to the seeds being used for ice creams, sweets, creams, jellies, liqueurs, and vitamin production. A physicochemical characterization of the fixed pulp oil and its antibacterial and aminoglycoside antibiotic modifying activity against Gram-positive and Gram-negative multiresistant bacterial strains were performed using broth microdilution assays. Physical properties, such as moisture, pH, acidity, peroxide index, relative density, and refractive index, indicated oil stability and chemical quality. In the GC/MS chemical composition analysis, a high content of unsaturated fatty acids (89.81%) in relation to saturated fatty acids (10.19%) was observed. Oleic acid (89.81%) was the main fatty acid identified. In the antibacterial test, the fixed oil obtained the Minimum Inhibitory Concentration (MIC) ≥ 1024 μg/mL for all standard and multiresistant bacterial strains. The synergic effect of fixed pulp oil combined was observed only in Staphylococcus aureus SA–10, with an MIC reduction of the gentamicin and amikacin by 40.00% and 60.55%, respectively. The data indicates the M. flexuosa fixed oil as a valuable source of oleic acid and modulator of aminoglycoside activity.

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Cytochemical Studies of Cell Wall Biosynthesis in Staphylococcus Aureus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094905 ◽

1972 ◽

Vol 30 ◽

pp. 328-329

Author(s):

Masaatsu Koike ◽

Koichi Nakashima ◽

Kyoko Iida

Keyword(s):

Staphylococcus Aureus ◽

Periodate Oxidation ◽

Early Time ◽

The Other ◽

Penicillin G ◽

Cell Wall Biosynthesis ◽

Septal Wall ◽

Peptidoglycan Biosynthesis ◽

Gram Positive Bacteria ◽

Cross Linkage

Penicillin exerts the activity to inhibit the peptide cross linkage between each polysaccharide backbone at the final stage of wall-peptidoglycan biosynthesis of bacteria. Morphologically, alterations of the septal wall and mesosome in gram-positive bacteria, which were occurred in early time after treatment with penicillin, have been observed. In this experiment, these alterations were cytochemically investigated by means of silver-methenamine staining after periodate oxidation, which is applied for detection of localization of wall mucopolysaccharide.Staphylococcus aureus strain 209P treated with 100 u/ml of penicillin G was divided into two aliquotes. One was fixed by Kellenberger-Ryter's OSO4 fixative at 30, 60 and 120 min after addition of the antibiotic, dehydrated through alcohol series, and embedded in Epon 812 (Specimen A). The other was fixed by 21 glutaraldehyde, dehydrated through glycolmethacrylate series and embedded in glycolmethacrylate mixture, according to Bernhard's method (Specimen B).

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Gold labeling of teichoic acid on adjacent surfaces of staphylococcus aureus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160443 ◽

1990 ◽

Vol 48 (3) ◽

pp. 578-579

Author(s):

Margaret Hukee

Keyword(s):

Staphylococcus Aureus ◽

Teichoic Acid ◽

Protein Labeling ◽

Minimal Amount ◽

Section Thickness ◽

Double Labeling ◽

Parallel Surfaces ◽

Supporting Membrane

Gold labeling of two antigens (double labeling) is often done on two section surfaces separated by section thickness. Whether labeling is done on both sides of the same section or on two parallel surfaces separated by section thickness (PSSST), comparable results are dependent on an equal number of epitopes being exposed at each surface. We propose a method to study protein labeling within the same field of proteins, by examining two directly adjacent surfaces that were split during sectioning. The number of labeling sites on adjacent surfaces (AS) were compared to sites on PSSST surfaces in individual bacteria.Since each bacteria needed to be recognizable in all three section surfaces, one-hole grids were used for labeling. One-hole grids require a supporting membrane and excessive handling during labeling often ruptures the membrane. To minimize handling, a labeling chamber was designed that is inexpensive, disposable, minimizes contamination, and uses a minimal amount of solution.

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