Search

Staphylococcal food poisoning is considered to be one of the most common foodborne illnesses worldwide. Because milk is rich in nutrients and its neutral pH, it leads to the growth of various bacteria. To date, the correlation between enterotoxigenic potential in Staphylococcus species and antimicrobial resistance (AMR), using bioinformatics analysis in buffalo and cow raw milk and the possible health risks from these bacteria, has not been examined in Egypt. A total of 42 Staphylococcus isolates representing 12 coagulase-positive staphylococci (Staphylococcus aureus and Staphylococcus intermedius) and 30 coagulase-negative staphylococci (Staphylococcus capitis, Staphylococcus xylosus, Staphylococcus carnosus, Staphylococcus saccharolyticus, and Staphylococcus auricularis) were isolated. An assay of the antimicrobial resistance phenotypes indicated low resistance against vancomycin (9.5%). The blaZ gene was associated with penicillin G and methicillin resistance and not with sulbactam + ampicillin. The presence of the gene ermB presented the correlation with erythromycin resistance and tetK with tetracycline resistance (correlation index: 0.57 and 0.49, respectively), despite the absence of the same behavior for ermC and tetM, respectively. Interestingly, the gene mecA was not correlated with resistance to methicillin or any other β-lactam. Correlation showed that slime-producing isolates had more resistance to antibiotics than those of nonslime producers. The multiple correlations between antibiotic resistance phenotypes and resistance genes indicate a complex nature of resistance in Staphylococcus species. The antimicrobial resistance could potentially spread to the community and thus, the resistance of Staphylococcus species to various antibiotics does not depend only on the use of a single antimicrobial, but also extends to other unrelated classes of antimicrobials.

There are various sources of microbial air pollution which are seems to be a serious public health problem all over the world. For prevention and control of air pollution caused by airborne bacteria, rapid, sensitive and reliable detection techniques are required. Therefore, our study focused on using MALDI Biotyper (MBT) for rapid recognition of various microbial air pollutants. Five hundred air samples were collected from three localities, including Qassim University (150 samples), Al-Qassim hospitals (250 samples) and poultry slaughter houses (100 samples). All air samples were collected by impactor air sampler from the indoor and outdoor environment. All samples were cultivated on nutrient and blood agar media for two days and a total of 129 isolates were purified for proteomic analysis using MALDI Biotyper (MBT) then confirmed by quantitative polymerase chain reaction (qPCR). One hundred and nineteen (92.25%) isolates were identified by MBT at the species level with a log (score) value ≥2. 000 whereas; 10 (7.75%) isolates were detected at the genus level with score values ranged from 1.7000 to 1.999. The MBT was able to identify 93 (72.10%) gram-positive and 36 (27.90%) gram-negative bacterial isolates. The most common genera were Staphylococcus (n = 43, 33.33%), Escherichia (n = 16, 12.40%), Enterococcus (n = 15, 11.63%) and Bacillus (n = 15, 11.63%). Staphylococcus aureus and Escherichia coli were the most frequently identified species (n = 16, 12.40% for each). In general, we detected 53 (41.10%) various bacterial species in Al-Qassim hospitals, 41 (31.79%) in poultry slaughter houses and 35 (27.13%) in Qassim University. Throughout Al-Qassim region, the air was tainted by numerous environmental microorganisms, and the MBT was positively adjusted for their fast and accurate identification.

Pseudomonas aeruginosa (P. aeruginosa) produces a suite of virulence factors that are coordinated by Quorum Sensing (QS) contributing to its disease-causing ability in aquaculture. The present study is first of its kind to obtain information regarding the presence and distribution of five QS genes, three virulence genes viz: lasI, lasR, rhlI, rhlR, rhlAB, toxA, aprA and plcH and seven of the Extended-spectrum βlactamases (blaVEB, blaPER, blaTEM,, blaSHV, blaCTX-M1, blaCTX-M2 and blaCTX-M3) of Pseudomonas species isolated from fish meat by direct PCR. Bacterial identification was based mainly on conventional biochemical techniques using the Vitek 2, automated system. Phenotypic sensitivity of antibiotics was established by the agar disc diffusion technique through 16 various antimicrobial drugs. Quantification of their in vitro production of numerous virulence genes outside the cell that are QS dependent namely, pyocyanin, elastase, alkaline protease, biofilm and cytotoxicity of Vero cell was as well executed. Fifteen genes demonstrated an enormous variety in their association. The total number of Pseudomonas species isolates were 30/100 to be identified by the API 20NE system as P. aeruginosa 12/30 (40%), P. fluorescens 8/30 (27%), P. putida 6/30 (20%) and P. alkylphenolia 4/30 (13%). The outcomes of this study have great significance for the strategic designation of QS quenching.