Phylogeny Characterization of Seb Gene Encoding Enterotoxins in Staphylococcus aureus Isolated from Raw Milk and Cheese

2019 ◽  
Vol 9 (o3) ◽  
Author(s):  
Fatima N. Aziz ◽  
Laith Abdul Hassan Mohammed-Jawad
Keyword(s):  
Staphylococcus Aureus ◽  
Food Poisoning ◽  
Raw Milk ◽  
Staphylococcal Enterotoxin B ◽  
Human Pathogen ◽  
Conventional Pcr ◽  
Biochemical Tests ◽  
Specific Primers ◽  
Gene Encoding

Food poisoning due to the bacteria is a big global problem in economically and human's health. This problem refers to an illness which is due to infection or the toxin exists in nature and the food that use. Milk is considered a nutritious food because it contains proteins and vitamins. The aim of this study is to detect and phylogeny characterization of staphylococcal enterotoxin B gene (Seb). A total of 200 milk and cheese samples were screened. One hundred ten isolates of Staphylococcus aureus pre-confirmed using selective and differential media with biochemical tests. Genomic DNA was extracted from the isolates and the SEB gene detects using conventional PCR with specific primers. Three staphylococcus aureus isolates were found to be positive for Seb gene using PCR and confirmed by sequencing. Sequence homology showed variety range of identity starting from (100% to 38%). Phylogenetic tree analyses show that samples (6 and 5) are correlated with S. epidermidis. This study discovered that isolates (A6-RLQ and A5-RLQ) are significantly clustered in a group with non- human pathogen Staphylococcus agnetis.

scholarly journals MOLECULAR DETECTION AND CHARACTERIZATION OF STAPHYLOCOCCUS AUREUS ISOLATED FROM RAW MILK SOLD IN DIFFERENT MARKETS OF BANGLADESH

2017 ◽  
Vol 14 (2) ◽  
pp. 277-282 ◽  
Author(s):  
M. A. Islam ◽  
S. M. L. Kabir ◽  
M. T. Rahman
Keyword(s):  
Molecular Detection ◽  
Culture Media ◽  
Raw Milk ◽  
Rrna Gene ◽  
Biochemical Tests ◽  
Selective Media ◽  
Milk Samples ◽  
Antimicrobial Sensitivity ◽  
Antimicrobial Sensitivity Test

The study was intended for molecular detection of S. aureus isolated from raw cow’s milk. A total of 20 milk samples were collected from different upazila markets of Jamalpur, Tangail, Kishoreganj and Netrokona districts of Bangladesh. Milk samples were cultured onto various culture media for the isolation of bacteria. The isolated bacteria were identified by studying cultural properties on different selective media, biochemical tests, and finally by PCR. Out of 20 samples, 15 (75%) milk samples were found to be positive for S. aureus. S. aureus specific 16S rRNA gene was amplified from all isolates and identified as S. aureus. Antimicrobial sensitivity test was carried out to ascertain the susceptibility of the organism to various antibiotics. Its results showed that the S. aureus isolates were resistant to amoxicillin (100%), erythromycin (73.33%) and tetracycline (73.33%) but sensitive to azithromycin (93.33%), ciprofloxacin (93.33%), gentamicin (100%), norfloxacin (86.67%) and streptomycin (86.67%).

scholarly journals Molecular Detection of Staphylococcal Enterotoxins and mecA Genes Products in Selected Food Samples Collected from Different Areas in Khartoum State

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Mohammed Yahya Ahmed ◽  
Hashim Abdalbagi Ali ◽  
Babbiker Mohammed Taher Gorish ◽  
Sara Omer Ali ◽  
Eman Saif Aldein Abdalrhim ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Meca Gene ◽  
Food Poisoning ◽  
Meat Products ◽  
Low Frequency ◽  
Raw Milk ◽  
Food Samples ◽  
Increased Risk ◽  
Enterotoxin B ◽  
Staphylococcus Aureus Enterotoxins

Staphylococcal food poisoning is an intoxication that results from the consumption of improperly prepared or stored foods containing sufficient amounts of one or more preformed S. aureus enterotoxins. Nowadays, many researchers worldwide noted an emergence of resistant strains such as Staphylococci particularly for the antibiotic methicillin. Therefore, this study was aimed to determine the existence of Staphylococcus aureus and its enterotoxins, mecA genes, in selected food samples. A total of 400 selected food samples were collected from different areas in Khartoum State. The selected foods included cheese, meat products, fish, and raw milk. One hundred samples from each type of food were cultivated, and the resultant growth yielded 137 (34.25%) S. aureus, 126 (31.5%) bacteria other than S. aureus, and 137 (34.25%) yielded no growth. Eighty-four of the 137 S. aureus isolates were randomly selected and tested for the presence of mecA and enterotoxin genes. The oxacillin sensitivity test showed that 15 (11%) of 137 S. aureus isolates were oxacillin resistant. The PCR assay showed that the mecA gene was detected in 15 of 84 (17%) S. aureus isolates. Simultaneously, only 2 (2.385%) out of 84 S. aureus isolates showed an enterotoxin B gene product. There was a relatively moderate prevalence of methicillin-resistant Staphylococcus aureus with very low frequency of enterotoxin B gene in different kinds of selected food samples collected from Khartoum State. These findings elucidate the increased risk on public in Khartoum being affected by Staphylococcal food poisoning upon consumption of dairy or meat products prepared in unhygienic conditions that could lead to intoxication by Staphylococcus aureus enterotoxins.

scholarly journals Growth characterisation of Staphylococcus aureus in milk: a quantitative approach

2009 ◽  
Vol 27 (No. 6) ◽  
pp. 433-453 ◽  
Author(s):  
A. Medveďová ◽  
Ľ. Valík ◽  
Z. Sirotná ◽  
D. Liptáková
Keyword(s):  
Staphylococcus Aureus ◽  
Growth Rate ◽  
Incubation Temperature ◽  
Food Poisoning ◽  
Raw Milk ◽  
Lag Phase ◽  
Phase Duration ◽  
Temperature Range ◽  
Root Model ◽  
Toxigenic Strains

<i>Staphylococcus aureus</i> is a pathogenic bacterium that induces several of human illnesses. The staphylococcal enterotoxin (SE) production as the results of previous growth of toxigenic strains is the most crucial problem which may lead to the staphylococcal food poisoning outbreaks in humans. That is why the growth of three strains of <i>Staphylococcus aureus</i> was characterised in milk and modelled in dependence of temperature. For the lag phase duration of <i>S. aureus</i> 2064, the Davey model was used with the following result: ln(1/lag) = 1.973 – 87.92/<i>T</i> + 285.09/<i>T</i><sup>2</sup> (<i>R</i><sup>2</sup> = 0.962). The dependence of the growth rate on incubation temperature was modelled by the Ratkowsky square root model and Gibson in sub-optimal and whole temperature range, respectively. The validation of both models showed high significance of the growth rate data fitting. The optimal temperature of <i>T</i><sub>opt</sub> = 38.5°C was resulted from Gibson model for the <i>S. aureus</i> 2064 growth in milk. For practical purpose, the time necessary for the increase of <i>S. aureus</i> by 3 log counts was also calculated within the growth temperature range. These data may provide useful information e.g. for the producers using raw milk in their artisanal cheese practice as the specific strains were used in this study.

scholarly journals Characterization of Staphylococcus aureus strains and evidence for the involvement of non-classical enterotoxin genes in food poisoning outbreaks

2018 ◽  
Vol 365 (13) ◽  
Author(s):  
Laurentiu-Mihai Ciupescu ◽  
Frederic Auvray ◽  
Isabela Madalina Nicorescu ◽  
Thomas Meheut ◽  
Veronica Ciupescu ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Food Poisoning ◽  
Enterotoxin Genes

scholarly journals Physical and Biochemical Characterization of the qacA Gene Encoding Antiseptic and Disinfectant Resistance in Staphylococcus aureus

Microbiology ◽  
1989 ◽  
Vol 135 (1) ◽  
pp. 1-10 ◽  
Author(s):  
J. M. TENNENT ◽  
B. R. LYON ◽  
M. MIDGLEY ◽  
G. JONES ◽  
A. S. PUREWAL ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Biochemical Characterization ◽  
Gene Encoding ◽  
Disinfectant Resistance

scholarly journals Molecular detection of Staphylococcal enterotoxins and mecA genes products in food samples collected from different areas in Khartoum state

2020 ◽  
Author(s):  
Mohammed Yahya ◽  
Hashim Abdalbagi Ali ◽  
Babbiker Mohammed Taher Gorish ◽  
Sara Omer Ali ◽  
Eman Saif Aldein Abdalrhim ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Meca Gene ◽  
Food Poisoning ◽  
Meat Products ◽  
Low Frequency ◽  
Raw Milk ◽  
Food Samples ◽  
Enterotoxin Genes ◽  
Resistant Strains ◽  
Enterotoxin B

Abstract Background Staphylococcal Food Poisoning is an intoxication that results from the consumption of improperly prepared or stored foods containing sufficient amounts of one or more preformed S. aureus enterotoxins. Now days many researchers worldwide noted an emerging of resistant strains Staphylococci especially for the antibiotic Methicillin. Therefore, this study was aimed to determine the existence of Staphylococcus aureus and its enterotoxins, mecA genes in food samples. Results A total of 400 samples were collected from different areas in Khartoum state. The type of foods included Cheese, Meat products, Fish and Raw milk, 100 samples for each. out of 400 samples cultivated 137 (34.25%) isolates were identified as S. aureus, 126 (31.5%) were identified as bacteria other than S. aureus and 137 (34.25%) were yield no growth. Of 137 S.aureus isolates, 84 were randomly selected and examined for the presence mecA and enterotoxin genes products. Oxacillin sensitivity test showed that 15(11%) of 137 S.aureus isolates were Oxacillin resistant. The PCR assay showed that mecA gene was detected in 15 of 84 (17%) S. aureus isolates. While only 2 (2.385%) out of 84 S. aureus isolates were show an enterotoxin B gene product. Conclusion There was a relatively moderate prevalence of Methicillin resistant staphylococcus aureus with very low frequency of enterotoxin B gene in different kinds of food samples which collected from Khartoum state. These findings highlight the high potential risk for consumers of meat and dairy products especially in the absence of strict hygienic and preventive measures to avoid Staphylococcus aureus enterotoxins production in foods.

Prevalence and characterization of Staphylococcus aureus isolated in raw milk from cows in Hokkaido, Japan

2019 ◽  
Vol 52 (4) ◽  
pp. 1631-1637
Author(s):  
Sukanya Thongratsakul ◽  
Masaru Usui ◽  
Hidetoshi Higuchi ◽  
Toshihiko Takahashi ◽  
Tomomi Sato ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Raw Milk

Occurrence of Staphylococcus aureus in fresh Indian Mackerel Fish

2020 ◽  
Vol 37 ◽  
pp. 7-16
Author(s):  
F.S. Ali ◽  
A.M. Lupindu ◽  
R.H. Mdegela ◽  
A.J. Mmoch
Keyword(s):  
Staphylococcus Aureus ◽  
Value Chain ◽  
Meca Gene ◽  
Food Poisoning ◽  
Biochemical Tests ◽  
Mannitol Salt Agar ◽  
Indian Mackerel ◽  
Two Samples ◽  
Landing Sites ◽  
Pcr Targeting

Fish provide important protein to human population. The procedures to preserve and maintain quality of fish from fishing until consumption can play a role in contamination with pathogens. Consumption of contaminated sea food products such as fish may lead to food poisoning. Knowledge about the spectrum of fish bacterial contaminants may assist in prevention of contamination and control food poisoning incidences. The present study aimed at characterizing and estimating prevalence of Staphylococcus aureus in fresh Indian Mackerel Fish (Rastrelliger kanagurta) from landing sites in Unguja Island. A total of 400 Indian Mackerel Fish were collected from landing sites in Unguja Island and from each fish two samples, skin swab and muscle, were collected. The primary culture was obtained from Mannitol salt agar, Nutrient and Blood agar followed by Gram staining, catalase coagulase tests. PCR targeting 16S rRNA, nuc, mecA, pvl, spa and enterotoxin genes was run to genetically characterize isolates and identify S. aureus. The result indicates that there was growth of bacteria in 359 (89.75%) fish skin swabs and 102 (25.5%) in fish muscle samples. Based on biochemical tests, 27 isolates (6.75%) were confirmed to be Staphylococcus bacteria. Of the 27 isolates, seven (1.75%) were confirmed S. aureus based on PCR. All 27 isolates confirmed to be positive in 16Sr RNA gene, two isolates demonstrated mecA gene and one had SEB and SEC. Detection of S. aureus in fresh Indian Mackerel Fish at landing sites poses a contamination risk to other critical points along the value chain and threatens public health

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