Capacity of adherence, invasion and intracellular survival of Streptococcus uberis biofilm‐forming strains

Mastitis is an infectious disease encountered in dairy animals worldwide that is currently a growing concern in Lebanon. This study aimed at investigating the etiology of the main mastitis-causing pathogens in Northern Lebanon, determining their antimicrobial susceptibility profiles, and identifying their antimicrobial resistance (AMR) genes. A total of 101 quarter milk samples were collected from 77 cows and 11 goats presenting symptoms of mastitis on 45 dairy farms. Bacterial identification was carried out through matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Antimicrobial susceptibility was tested by disc diffusion and broth microdilution methods. Molecular characterization included polymerase chain reaction (PCR) screening for genes encoding extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated AmpC among Enterobacterales isolates, and virulence factors among Staphylococcus isolates. Escherichia coli isolates were subjected to phylogenetic typing by a quadruplex PCR method. The most frequently identified species were Streptococcus uberis (19.2%), Streptococcus agalactiae (15.1%), E. coli (12.3%), and Staphylococcus aureus (10.96%). Gram-positive bacteria were resistant to macrolides and tetracycline, whereas gram-negative bacteria displayed resistance to ampicillin and tetracycline. Two ESBL genes, blaTEM (83.3%) and blaOXA (16.7%), and one AmpC beta-lactamase gene, blaCMY-II (16.7%), were detected among six E. coli isolates, which mainly belonged to phylogenetic group B1. Among Staphylococcus spp., the mecA gene was present in three isolates. Furthermore, four isolates contained at least one toxin gene, and all S. aureus isolates carried the ica operon. These findings revealed the alarming risk of AMR in the Lebanese dairy chain and the importance of monitoring antimicrobial usage.

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Influence of nutrient availability on in vitro growth of major bovine mastitis pathogens

Journal of Dairy Research ◽

10.1017/s0022029921000133 ◽

2021 ◽

Vol 88 (1) ◽

pp. 80-88

Author(s):

Remo Stürmlin ◽

Josef J. Gross ◽

Olga Wellnitz ◽

Lea A. Wagner ◽

Camille Monney ◽

...

Keyword(s):

Bacterial Growth ◽

Nutrient Availability ◽

Bovine Mastitis ◽

Milk Composition ◽

B Vitamins ◽

E Coli ◽

Streptococcus Uberis ◽

Whole Milk ◽

Mastitis Pathogens

AbstractThe aim of the present study was to investigate the effects of milk composition changes on the in vitro growth of bovine mastitis pathogens. Nutritional requirements of three major bovine mastitis pathogens Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Streptococcus uberis (S. uberis) were investigated in vitro. We used ultra-high temperature (UHT) treated milk with different contents of fat, protein, and carbohydrates to test the influence of the availability of various milk constituents on pathogen growth characteristics. Additionally, the bacterial growth was investigated under experimentally modified nutrient availability by dilution and subsequent supplementation with individual nutrients (carbohydrates, different nitrogen sources, minerals, and different types of B vitamins) either to milk or to a conventional medium (thioglycolate broth, TB). Varying contents of fat, protein or lactose did not affect bacterial growth with the exception of growth of S. uberis being promoted in protein-enriched milk. The addition of nutrients to diluted whole milk and TB partly revealed different effects, indicating that there are media-specific growth limiting factors after dilution. Supplementation of minerals to diluted milk did not affect growth rates of all studied bacteria. Bacterial growth in diluted whole milk was decreased by the addition of high concentrations of amino acids in S. aureus, and by urea and additional B vitamins in E. coli and S. aureus. The growth rate of S. uberis was increased by the addition of B vitamins to diluted whole milk. The present results demonstrate that growth-limiting nutrients differ among pathogen types. Because reduced bacterial growth was only shown in diluted milk or TB, it is unlikely that alterations in nutrient availability occurring as a consequence of physiological changes of milk composition in the cow's udder would directly affect the susceptibility or course of bovine mastitis.

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Post-translational knockdown and post-secretional modification of EsxA determine contribution of EsxA membrane permeabilizing activity for mycobacterial intracellular survival

Virulence ◽

10.1080/21505594.2020.1867438 ◽

2020 ◽

Author(s):

Yanqing Bao ◽

Lin Wang ◽

Jianjun Sun

Keyword(s):

Intracellular Survival

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M. tuberculosis PknG manipulates host autophagy flux to promote pathogen intracellular survival

Autophagy ◽

10.1080/15548627.2021.1938912 ◽

2021 ◽

Author(s):

Pupu Ge ◽

Zehui Lei ◽

Yang Yu ◽

Zhe Lu ◽

Lihua Qiang ◽

...

Keyword(s):

Intracellular Survival ◽

Autophagy Flux

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MicroRNA-146a inhibits autophagy to maintain the intracellular survival of Burkholderia pseudomallei by targeting LIPA

Microbial Pathogenesis ◽

10.1016/j.micpath.2021.104969 ◽

2021 ◽

pp. 104969

Author(s):

Zhi-qiang Hu ◽

Qian Li ◽

Zhen-hong Hu ◽

Hai-chao Liu ◽

Cheng-long Rao ◽

...

Keyword(s):

Burkholderia Pseudomallei ◽

Intracellular Survival

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Prediction of Streptococcus uberis clinical mastitis treatment success in dairy herds by means of mass spectrometry and machine-learning

Scientific Reports ◽

10.1038/s41598-021-87300-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Alexandre Maciel-Guerra ◽

Necati Esener ◽

Katharina Giebel ◽

Daniel Lea ◽

Martin J. Green ◽

...

Keyword(s):

Machine Learning ◽

Mass Spectrometry ◽

Treatment Success ◽

Clinical Mastitis ◽

Supervised Machine Learning ◽

Structural Protein ◽

Cohen’S Kappa ◽

Maldi Tof ◽

Streptococcus Uberis ◽

Cohen's Kappa

AbstractStreptococcus uberis is one of the leading pathogens causing mastitis worldwide. Identification of S. uberis strains that fail to respond to treatment with antibiotics is essential for better decision making and treatment selection. We demonstrate that the combination of supervised machine learning and matrix-assisted laser desorption ionization/time of flight (MALDI-TOF) mass spectrometry can discriminate strains of S. uberis causing clinical mastitis that are likely to be responsive or unresponsive to treatment. Diagnostics prediction systems trained on 90 individuals from 26 different farms achieved up to 86.2% and 71.5% in terms of accuracy and Cohen’s kappa. The performance was further increased by adding metadata (parity, somatic cell count of previous lactation and count of positive mastitis cases) to encoded MALDI-TOF spectra, which increased accuracy and Cohen’s kappa to 92.2% and 84.1% respectively. A computational framework integrating protein–protein networks and structural protein information to the machine learning results unveiled the molecular determinants underlying the responsive and unresponsive phenotypes.

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Intracellular survival of Shigella

Cellular Microbiology ◽

10.1111/j.1462-5822.2005.00652.x ◽

2006 ◽

Vol 8 (2) ◽

pp. 177-184 ◽

Cited By ~ 49

Author(s):

Michinaga Ogawa ◽

Chihiro Sasakawa

Keyword(s):

Intracellular Survival

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Feeding a Saccharomyces cerevisiae fermentation product improves udder health and immune response to a Streptococcus uberis mastitis challenge in mid-lactation dairy cows

Journal of Animal Science and Biotechnology ◽

10.1186/s40104-021-00560-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

M. Vailati-Riboni ◽

D. N. Coleman ◽

V. Lopreiato ◽

A. Alharthi ◽

R. E. Bucktrout ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Somatic Cell ◽

Pathway Analysis ◽

Molecular Mechanisms ◽

Somatic Cell Score ◽

Molecular Networks ◽

Epithelial Tissue ◽

Udder Health ◽

Streptococcus Uberis ◽

Fermentation Product

Abstract Background We aimed to characterize the protective effects and the molecular mechanisms of action of a Saccharomyces cerevisiae fermentation product (NTK) in response to a mastitis challenge. Eighteen mid-lactation multiparous Holstein cows (n = 9/group) were fed the control diet (CON) or CON supplemented with 19 g/d NTK for 45 d (phase 1, P1) and then infected in the right rear quarter with 2500 CFU of Streptococcus uberis (phase 2, P2). After 36-h, mammary gland and liver biopsies were collected and antibiotic treatment started until the end of P2 (9 d post challenge). Cows were then followed until day 75 (phase 3, P3). Milk yield (MY) and dry matter intake (DMI) were recorded daily. Milk samples for somatic cell score were collected, and rectal and udder temperature, heart and respiration rate were recorded during the challenge period (P2) together with blood samples for metabolite and immune function analyses. Data were analyzed by phase using the PROC MIXED procedure in SAS. Biopsies were used for transcriptomic analysis via RNA-sequencing, followed by pathway analysis. Results DMI and MY were not affected by diet in P1, but an interaction with time was recorded in P2 indicating a better recovery from the challenge in NTK compared with CON. NTK reduced rectal temperature, somatic cell score, and temperature of the infected quarter during the challenge. Transcriptome data supported these findings, as NTK supplementation upregulated mammary genes related to immune cell antibacterial function (e.g., CATHL4, NOS2), epithelial tissue protection (e.g. IL17C), and anti-inflammatory activity (e.g., ATF3, BAG3, IER3, G-CSF, GRO1, ZFAND2A). Pathway analysis indicated upregulation of tumor necrosis factor α, heat shock protein response, and p21 related pathways in the response to mastitis in NTK cows. Other pathways for detoxification and cytoprotection functions along with the tight junction pathway were also upregulated in NTK-fed cows. Conclusions Overall, results highlighted molecular networks involved in the protective effect of NTK prophylactic supplementation on udder health during a subclinical mastitic event.

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