Molecular detection of methicillin heat-resistant Staphylococcus aureus strains in pasteurized camel milk in Saudi Arabia

Abstract

Antibiotic- and heat-resistant bacteria in camel milk is a potential public health problem. Staphylococcus aureus (S. aureus) is an opportunistic pathogen in humans, dairy cattle and camels. We characterized the phenotype and genotype of methicillin-resistant staphylococcal strains recovered from pasteurized and raw camel milk (as control) distributed in the retail markets of Saudi Arabia. Of the 100 samples assessed between March and May 2016, 20 S. aureus isolates were recovered from pasteurized milk, 10 of which were resistant to cefoxitin, and as such, were methicillin-resistant. However, raw camel milk did not contain methicillin-resistant S. aureus (MRSA). Antimicrobial susceptibility tests showed that the resistance ratio for other antibiotics was 60%. We performed a polymerase chain reaction (PCR) assay using primers for the methicillin-resistant gene mecA and nucleotide sequencing to detect and verify the methicillin-resistant strains. Basic local alignment search tool (BLAST) analysis of the gene sequences showed a 96–100% similarity between the resistant isolates and the S. aureus CS100 strain’s mecA gene. Ten of the methicillin-resistant isolates were heat-resistant and were stable at temperatures up to 85°C for 60 s, and three of these were resistant at 90°C for 60 or 90 s. The mean decimal reduction time (D85-value) was 111 s for the ten isolates. Sodium dodecyl sulfate (SDS)/polyacrylamide gel electrophoresis (PAGE) showed that there was no difference in the total protein profiles for the ten methicillin heat-resistant S. aureus (MHRSA) isolates and for S. aureus ATCC 29737. In conclusion, a relatively high percentage of the tested pasteurized camel milk samples contained S. aureus (20%) and MHRSA (10%).

<p>miR-877-5p Suppresses Gastric Cancer Cell Proliferation Through Targeting FOXM1</p>

“…8,9 Therefore, exploring the aberrant expression of miRNAs and their functional role in GC may lead to new GC diagnostics and therapeutics. Previous studies have shown that miR-877-5p may serve as a tumor suppressor factor in cervical cancer 10 and glioblastoma. 11 The miR-877 family has also been shown to participate in cancer progression.…”

Methicillin-Resistant Staphylococcus aureus (MRSA) and Other Methicillin-Resistant Staphylococci and Mammaliicoccus (MRNaS) Associated with Animals and Food Products in Arab Countries: A Review

“…While there are data on S. aureus and MRSA on camel-derived food products [ 114 , 115 , 116 ], there is only one study that confirms the presence of methicillin resistance in S. aureus in these animals [ 61 ]. The MRSA isolates belonged to the European community-associated CA-MRSA CC80, which could indicate that the origin of these strains is human as it is one of the most reported CCs in humans in the Arab world [ 117 ].…”

“…In Arab countries, MRSA has been reported to be present in different types of foods ( Table 3 ), such as beef, poultry meat, raw cow’s milk, and camel and sheep milk [ 114 , 115 , 135 , 136 , 137 , 138 , 139 , 140 , 141 ], but if MRSA can act as a food-borne pathogen remains unclear. CA-MRSA, LA-MRSA and even HA-MRSA in foods have been reported in these countries [ 141 , 142 ], revealing both the human and animal origin of the strains [ 116 ].…”

<p>MicroRNA-154: A Novel Candidate for Diagnosis and Therapy of Human Cancers</p>

“…Furthermore, they proved that both miRNA suppress progression of thyroid cancer by synergistically targeting ROHA and blocking its expression. 70 Taking together, the aforementioned studies initially suggest that miR-154 may be employed for prognosis and diagnosis of endocrine cancers, however, its precise tumor suppressor role and the beyond mechanisms should be deeply investigated.…”