Essential Role for Estrogen in Protection againstVibrio vulnificus-Induced Endotoxic Shock

ABSTRACT Little is known about the underlying mechanisms that result in a sexually dimorphic response to Vibrio vulnificus endotoxic shock. V. vulnificus is a gram-negative bacterium, considered one of the most invasive and rapidly fatal human pathogens known. However, 85% of individuals that develop endotoxic shock fromV. vulnificus are males. Using the rat, we have developed a model for V. vulnificus endotoxic shock that mimics the sexually dimorphic response in humans. Gonadectomy in females results in increased mortality, and estrogen replacement results in decreased mortality in both gonadectomized males and females. These results demonstrate that estrogen is providing protection against V. vulnificus lipopolysaccharide-induced endotoxic shock.

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Draft Genome Sequences of 42 Environmental Vibrio vulnificus Strains Isolated from the Northern Gulf of Mexico

Microbiology Resource Announcements ◽

10.1128/mra.00200-19 ◽

2019 ◽

Vol 8 (28) ◽

Author(s):

Megan M. Mullis ◽

I-Shuo Huang ◽

Githzette M. Planas-Costas ◽

Reavelyn Pray ◽

Gregory W. Buck ◽

...

Keyword(s):

Gulf Of Mexico ◽

Necrotizing Fasciitis ◽

Vibrio Vulnificus ◽

Draft Genome ◽

Opportunistic Pathogen ◽

Negative Bacterium ◽

Genome Sequences ◽

Gram Negative ◽

Content Type ◽

Northern Gulf Of Mexico

Vibrio vulnificus is a Gram-negative bacterium and an opportunistic pathogen that can cause septicemia or necrotizing fasciitis. Here, we report the draft genome sequences of 42 environmental V. vulnificus strains collected from the northern Gulf of Mexico. These data will allow for more robust comparisons between clinical and environmental strains.

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Oral Pathogenic Bacteria-Inducing Neurodegenerative Microgliosis in Human Neural Cell Platform

International Journal of Molecular Sciences ◽

10.3390/ijms22136925 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6925

Author(s):

Tran Thi Ai Tran ◽

You Jung Kang ◽

Hyun-Kyoung Kim ◽

Hyung-Ryong Kim ◽

Hansang Cho

Keyword(s):

Inflammatory Markers ◽

Pathogenic Bacteria ◽

Neurological Diseases ◽

Neural Cells ◽

Negative Bacterium ◽

Gram Negative ◽

Human Neural Cells ◽

Underlying Mechanisms ◽

Human Neural Cell ◽

Ptau Level

Porphyromonas gingivalis is a gram-negative bacterium found in the human oral cavity and is responsible for the development of chronic periodontitis as well as neurological diseases, including Alzheimer’s disease (AD). Given the significance of the roles of P. gingivalis in AD pathogenesis, it is critical to understand the underlying mechanisms of P. gingivalis-driven neuroinflammation and their contribution to neurodegeneration. Herein, we hypothesize that P. gingivalis produces secondary metabolites that may cause neurodegeneration through direct or indirect pathways mediated by microglia. To test our hypothesis, we treated human neural cells with bacterial conditioned media on our brain platforms and assessed microgliosis, astrogliosis and neurodegeneration. We found that bacteria-mediated microgliosis induced the production of nitric oxide, which causes neurodegeneration assessed with high pTau level. Our study demonstrated the elevation of detrimental protein mediators, CD86 and iNOS and the production of several pro-inflammatory markers from stimulated microglia. Through inhibition of LPS and succinate dehydrogenase in a bacterial conditioned medium, we showed a decrease in neurodegenerative microgliosis. In addition, we demonstrated the bidirectional effect of microgliosis and astrogliosis on each other exacerbating neurodegeneration. Overall, our study suggests that the mouth-brain axis may contribute to the pathogenesis of AD.

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Genome sequence of Vibrio sp. OULL4 isolated from shellfish

Progress In Microbes & Molecular Biology ◽

10.36877/pmmb.a0000066 ◽

2020 ◽

Vol 3 (1) ◽

Cited By ~ 1

Author(s):

Vengadesh Letchumanan ◽

Wen-Si Tan ◽

Wai-Fong Yin ◽

Kok-Gan Chan

Keyword(s):

Vibrio Cholerae ◽

Genome Sequence ◽

Vibrio Parahaemolyticus ◽

Vibrio Vulnificus ◽

Diverse Group ◽

Seafood Consumption ◽

Negative Bacterium ◽

Antibiotic Resistant ◽

Gram Negative ◽

Resistant Strains

The members of Vibrionaceae family are Gram-negative bacterium are ubiquitous in marine and estuarine environments. This diverse group of bacteria include many pathogenic strains that potentially cause infection to humanand aquaculture animals. Vibrio cholerae, Vibrio parahaemolyticus and Vibrio vulnificus are among the few recognized as a major, worldwide cause gastroenteritis, particularly in countries where seafood consumption is high. The control of these vibrios has been a hurdle due to the rising numbers of antibiotic resistant strains in the environments. We report the genome sequence of Vibrio sp. OULL4 isolated from shellfish. The availability of this genome sequence will facilitate the study of its antimicrobial traits, as well as add our knowledge of Vibrio sp. diversity and evolution.

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Thermal Inactivation of Listeria monocytogenes and Salmonella during Water and Steam Blanching of Vegetables

Journal of Food Protection ◽

10.4315/0362-028x.jfp-16-517 ◽

2017 ◽

Vol 80 (9) ◽

pp. 1550-1556 ◽

Cited By ~ 6

Author(s):

Erdogan Ceylan ◽

Wendy McMahon ◽

Donna M. Garren

Keyword(s):

Listeria Monocytogenes ◽

Thermal Inactivation ◽

Hot Water ◽

Human Pathogens ◽

Negative Bacterium ◽

Positive Bacterium ◽

Gram Positive ◽

Gram Negative ◽

Microbiological Safety ◽

Log Reduction

ABSTRACT Thermal inactivation of Listeria monocytogenes and Salmonella was evaluated on peas, spinach, broccoli, potatoes, and carrots that were treated with hot water and steam. One gram-positive bacterium, L. monocytogenes, and one gram-negative bacterium, Salmonella, were selected as pertinent human pathogens for evaluation. Samples were inoculated with a composite of five strains each of L. monocytogenes and Salmonella to achieve approximately 108 to 109 CFU/g. Inoculated samples were treated with hot water at 85 and 87.8°C and with steam at 85 and 96.7°C for up to 3.5 min. A greater than 5-log reduction of L. monocytogenes and Salmonella was achieved on all products within 0.5 min by hot water blanching at 85 and 87.8°C. Steam blanching at 85°C reduced Salmonella populations by greater than 5 log on spinach and peas within 2 min and on carrots and broccoli within 3.5 min. Populations of Salmonella were reduced by more than 5 log within 1 min on carrot, spinach, and broccoli and within 2 min on peas by steam blanching at 96.7°C. Steam blanching at 85°C reduced L. monocytogenes populations by more than 5 log on carrots and spinach within 2 min and on broccoli and peas within 3.5 min. L. monocytogenes populations were reduced more than 5 log within 1 min on carrot, spinach, peas and broccoli by steam blanching at 96.7°C. Longer treatment times and higher temperatures were required for steam-blanched samples than for samples blanched with hot water. Results suggest that hot water and steam blanching practices commonly used by the frozen vegetable industry will achieve the desired 5-log lethality of L. monocytogenes and Salmonella and will enhance microbiological safety prior to freezing.

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Local cytokine levels associated with delayed-type hypersensitivity responses: modulation by gender, ovariectomy, and estrogen replacement

Journal of Endocrinology ◽

10.1677/joe-06-0024 ◽

2007 ◽

Vol 193 (2) ◽

pp. 291-297 ◽

Cited By ~ 13

Author(s):

Lisa J Ma ◽

Esther A Guzmán ◽

Ariel DeGuzman ◽

H Konrad Muller ◽

Ameae M Walker ◽

...

Keyword(s):

Immune Responses ◽

Delayed Type Hypersensitivity ◽

Estrogen Replacement ◽

Active Response ◽

Cytokine Levels ◽

Before And After ◽

Males And Females ◽

Underlying Mechanisms ◽

First Time ◽

Local Cytokine

It is well established that females mount stronger immune responses than males, but only very little is understood about the underlying mechanisms. We have analyzed local cytokine differences among intact females, those that had been ovariectomized (OVX), those receiving estrogen replacement after OVX, and males, both before and after production of delayed-type hypersensitivity (DTH) responses. We report confirmation of a much larger DTH response in females versus males. However, OVX resulted in an even larger response, while estrogen replacement resulted in a smaller response when compared with intact females. In animals exposed for the first time to an antigen (without a DTH response), OVX increased interleukin-6 (IL-6) and estrogen replacement after OVX suppressed IL-6. Of the cytokines that differed between males and females exposed for the first time to an antigen, only IL-6 was higher in females versus males when exposure to antigen occurred for the second time (when the DTH response occurs). Analysis of cytokines with OVX and estrogen replacement after a second exposure to antigen showed that IL-6 did not significantly change. Levels of IL-4; Regulated upon Activation, Normal T-cell Expressed; and Secreted; and thrombopoietin, however, correlated with the DTH response, suggesting direct or indirect positive regulation by estrogen. These results suggest an important role for both IL-6 and IL-4 in determining the degree of DTH response, with IL-6 (which appears negatively regulated by estrogen) increasing and IL-4 (which appears positively regulated by estrogen) decreasing the response. The results further suggest that IL-6 may play a role in predisposing to a larger DTH response, while IL-4 levels seem more important during an active response.

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Isolation of d-Talomethylose (6-Deoxy-d-talose) and d-Rhamnose (6-Deoxy-d-mannose) from Capsular Polysaccharide of a Gram-negative Bacterium

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)73934-9 ◽

1962 ◽

Vol 237 (6) ◽

pp. 1767-1771

Author(s):

Alvin Markovitz

Keyword(s):

Capsular Polysaccharide ◽

Negative Bacterium ◽

Gram Negative

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Massiliamide, a cyclic tetrapeptide with potent tyrosinase inhibitory properties from the Gram-negative bacterium Massilia albidiflava DSM 17472T

The Journal of Antibiotics ◽

10.1038/s41429-020-00394-y ◽

2020 ◽

Author(s):

Andri Frediansyah ◽

Jan Straetener ◽

Heike Brötz-Oesterhelt ◽

Harald Gross

Keyword(s):

Absolute Configuration ◽

Inhibitory Activity ◽

Liquid Culture ◽

Spectroscopic Analysis ◽

2D Nmr ◽

Negative Bacterium ◽

Gram Negative ◽

The Absolute ◽

Potent Inhibitory Activity ◽

Cyclic Tetrapeptide

AbstractA cyclic tetrapeptide, designated massiliamide, was isolated from the liquid culture of the Gram-negative bacterium Massilia albidiflava DSM 17472T. The structure was elucidated through extensive spectroscopic analysis, including HR-MS and 1D and 2D NMR experiments. The absolute configuration was determined using the Marfey´s method. Massiliamide showed potent inhibitory activity towards tyrosinase with an IC50 value of 1.15 µM and no cytotoxicity.

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Porphyromonas gingivalis fimbrial protein Mfa5 contains a von Willebrand factor domain and an intramolecular isopeptide

Communications Biology ◽

10.1038/s42003-020-01621-w ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Thomas V. Heidler ◽

Karin Ernits ◽

Agnieszka Ziolkowska ◽

Rolf Claesson ◽

Karina Persson

Keyword(s):

Porphyromonas Gingivalis ◽

Von Willebrand Factor ◽

Host Cells ◽

Negative Bacterium ◽

Oral Biofilm ◽

Gram Negative ◽

Type V ◽

Von Willebrand ◽

Willebrand Factor ◽

Fimbrial Protein

AbstractThe Gram-negative bacterium Porphyromonas gingivalis is a secondary colonizer of the oral biofilm and is involved in the onset and progression of periodontitis. Its fimbriae, of type-V, are important for attachment to other microorganisms in the biofilm and for adhesion to host cells. The fimbriae are assembled from five proteins encoded by the mfa1 operon, of which Mfa5 is one of the ancillary tip proteins. Here we report the X-ray structure of the N-terminal half of Mfa5, which reveals a von Willebrand factor domain and two IgG-like domains. One of the IgG-like domains is stabilized by an intramolecular isopeptide bond, which is the first such bond observed in a Gram-negative bacterium. These features make Mfa5 structurally more related to streptococcal adhesins than to the other P. gingivalis Mfa proteins. The structure reported here indicates that horizontal gene transfer has occurred among the bacteria within the oral biofilm.

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