An-Najah Staff

Enterotoxin genes (sea-see) in Staphylococcus aureus isolates recovered from milk of clinically healthy sheep and cows in the north of Palestine were determined using a polymerase chain reaction (PCR). Thirty-seven (37%) out of 100 S. aureus isolates were toxin gene positive. Four strains (10.8%) were sea-positive, 20 (54.1%) were seb-positive, 4 (10.8%) were sec-positive, 6 (16.2%) were sed-positive and 3 (8.1%) were see-positive. None of these enterotoxigenic isolates carried more than one toxin gene. This study indicates that the presence of enterotoxigenic S. aureus in raw milk can contribute to the sources of staphylococcal food poisoning in Palestine.

Objectives: Staphylococcus aureus is an important pathogen associated with diseases in a variety of hosts including humans. It produces several toxins and virulence factors that contribute to its pathogenic potential such as staphylococcal enterotoxins (SEs). This study was conducted to determine enterotoxigenicity of S. aureus associated with chronic urogenital tract infection by detectingenterotoxin genes.
Setting: This study was done in The Microbiology laboratory, An-Najah N. University, Palestine.
Methodology: A total of 90 S. aureus isolates recovered from clinical samples from patients suffering from chronic urogenital tract infection in the North of Palestine were used to detect the presence of staphylococcal enterotoxin genes sea, seb, sec, sed and see by polymerase chain reaction (PCR) assay.
Results: Out of 90 S. aureus isolates tested, it was found that 57 (63.3%) of these isolates harboured one or more enterotoxin genes. Up to 78.9% of the enterotoxigenic isolates possessed one SE gene. The majority of these enterotoxigenic strains (61.4%) isolated from both semen and urine samples harbored sec gene either alone or in combination with other genes. Also the prevalence of genes in combination was significantly more common in S. aureus isolates derived from urine 9/33 (27.3%), as compared to those derived from semen 3/24 (12.5%).
Conclusions: The role of enterotoxin genes in the pathogenesis of urogenital tract infection is still unknown. However, it is evident that urogenital infection can be caused by S. aureus strains which lack these genes. Other newly detected genes may play a role in pathogenesis.

Prevalence of seg, she and sei Genes among Clinical and Nasal Staphylococus aureus Isolates in Palestine was studied.

Abstract: Aims: To investigate the presence of the staphylococcal enterotoxin genes seg, seh and sei among clinical and nasal isolates. Place and Duration of Study: Department of Biology and Biotechnology, An-Najah N. University, Palestine, in 2011. Methodology: A total 124 S. aureus isolates were collected, forty three were nasal and 81 were clinical isolates. PCR technique was used to detect enterotoxin genes seg, seh and sei, mecA gene and analysis of SCCmec types. Enterotoxigenic strains were also typed using coagulase typing kit. Results: Fifty two (41.9%) isolates were positive for one or more of these enterotoxin genes. The prevalence of toxin genes among S. aureus isolated from nasal swabs 25/43 (58.1%) was higher than those isolated from clinical samples 27/81 (33.3%). Combination of the toxin genes was noted only in MSSA isolate from both nasal swabs and clinical samples. Distribution of toxin genes in MSSA isolates was higher (49.5%) than those in MRSA isolates (21.2%). SCCmec typing showed that the MRSA enterotoxigenic strain were belonged to types II, III and IVa. MRSA strains were found to belong to coagulase

Aims: To investigate the presence of the staphylococcal enterotoxin genes seg, seh and sei among clinical and nasal isolates.
Place and Duration of Study: Department of Biology and Biotechnology, An-Najah N. University, Palestine, in 2011.
Methodology: A total 124 S. aureus isolates were collected, forty three were nasal and 81 were clinical isolates. PCR technique was used to detect enterotoxin genes seg, seh and sei, mecA gene and analysis of SCCmec types. Enterotoxigenic strains were also typed using coagulase typing kit.
Results: Fifty two (41.9%) isolates were positive for one or more of these enterotoxin genes. The prevalence of toxin genes among S. aureus isolated from nasal swabs 25/43 (58.1%) was higher than those isolated from clinical samples 27/81 (33.3%). Combination of the toxin genes was noted only in MSSA isolate from both nasal swabs and clinical samples. Distribution of toxin genes in MSSA isolates was higher (49.5%) than those in MRSA isolates (21.2%). SCCmec typing showed that the MRSA enterotoxigenic strain were belonged to types II, III and IVa. MRSA strains were found to belong to coagulase serotypes II, III and VII, while MSSA strains were belonged to serotypes II-VII. In nasal samples, 16/25 (64.0%) of enterotoxigenic strains showed the genotype seg+/sei+, while in clinical samples 1/27 (3.7%), 1/27 (3.7%) and 3/27 (11.1%) of enterotoxigenic strains showed the genotypes seg+/seh+, seg+/sei+ and seg+/seh+/sei+, respectively. This study showed that the majority of the isolates 42/124 (33.9%) were seg+, while none of nasal strains harbored seh gene.
Conclusion: The prevalence of seg, seh and sei genes in the S. aureus isolated from nasal swabs differed significantly from those obtained from clinical samples, as well as the prevalence of the same genes in MSSA differed significantly from those in MRSA. In addition, S. aureus isolates from clinical and nasal swabs could serve as a possible reservoir of newly described seg, seh and sei genes.

Aims: To investigate the presence of the staphylococcal enterotoxin genes seg, seh and sei among clinical and nasal isolates. Place and Duration of Study: Department of Biology and Biotechnology, An-Najah N. University, Palestine, in 2011. Methodology: A total 124 S. aureus isolates were collected, forty three were nasal and 81 were clinical isolates. PCR technique was used to detect enterotoxin genes seg, seh and sei, mecA gene and analysis of SCCmec types. Enterotoxigenic strains were also typed using coagulase typing kit. Results: Fifty two (41.9%) isolates were positive for one or more of these enterotoxin genes. The prevalence of toxin genes among S. aureus isolated from nasal swabs 25/43 (58.1%) was higher than those isolated from clinical samples 27/81 (33.3%). Combination of the toxin genes was noted only in MSSA isolate from both nasal swabs and clinical samples. Distribution of toxin genes in MSSA isolates was higher (49.5%) than those in MRSA isolates (21.2%). SCCmec typing showed that the MRSA enterotoxigenic strain were belonged to types II, III and IVa. MRSA strains were found to belong to coagulase  serotypes II, III and VII, while MSSA strains were belonged to serotypes II-VII. In nasal samples, 16/25 , (64.0%) of enterotoxigenic strains the showed the genotype   while in clinical samples 1/27  + /seh + , seg + /sei + and seg + /seh + /sei + , respectively. This study showed that the majority of the isolates 42/124  + , while none of nasal strains harbored seh gene.
Conclusion: The prevalence of seg, seh and sei genes in the S. aureus isolated from nasal swabs differed significantly from those obtained from clinical samples, as well as the prevalence of the same genes in MSSA differed significantly from those in MRSA. In addition, S. aureus isolates from clinical and nasal swabs could serve as a possible reservoir of newly described seg, seh and sei genes. + /sei

Abstract - A total of 68 Staphylococcus aureus strains isolated from different human clinical samples in the North of Palestine were examined to detect staphylococcal enterotoxin (SE) genes A (sea), B (seb), C (sec), D (sed) and (see). Of the total isolates examined, 41.2% (28/68) were enterotoxigenic S. aureus. Twelve strains (42.9%) of enterotoxigenic S. aureus harbored seagene, ten strains (35.7%) were carried see- gene, six strains (21.4%) were positive for sec-gene. None of these enterotoxigenic S. aureus isolates harbored more than one of toxin genes. The presence of these toxin genes and other genes not be detected here might play a role in process of pathogenesis of S. aureus disease other than food poisoning but this cannot be substantiated by the results of the present study. Keywords: Enterotoxigenic S. aureus, staphylococcal enterotoxins, SEs, Palestine.

Objectives: Staphylococcus aureus is an important pathogen associated with diseases in a variety of hosts including humans. It produces several toxins and virulence factors that contribute to its pathogenic potential such as staphylococcal enterotoxins (SEs). This study was conducted to determine enterotoxigenicity of S. aureus associated with chronic urogenital tract infection by detecting enterotoxin genes. Setting: This study was done in The Microbiology laboratory, An-Najah N. University, Palestine. Methodology: A total of 90 S. aureus isolates recovered from clinical samples from patients suffering from chronic urogenital tract infection in the North of Palestine were used to detect the presence of staphylococcal enterotoxin genes sea , seb , sec, sed and see by polymerase chain reaction (PCR) assay. Results: Out of 90 S. aureus isolates tested, it was found that 57 (63.3%) of these isolates harboured one or more enterotoxin genes. Up to 78.9% of the enterotoxigenic isolates possessed one SE gene. The majority of these enterotoxigenic strains (61.4%) isolated from both semen and urine samples harbored sec gene either alone or in combination with other genes. Also the prevalence of genes in combination was significantly more common in S. aureus isolates derived from urine 9/33 (27.3%), as compared to those derived from semen 3/24 (12.5%). Conclusions: The role of enterotoxin genes in the pathogenesis of urogenital tract infection is still unknown. However, it is evident that urogenital infection can be caused by S. aureus strains which lack these genes. Other newly detected genes may play a role in pathogenesis.

Enterotoxin genes ( sea-see ) in Staphylococcus aureus isolates recovered from milk of clinically healthy sheep and cows in the north of Palestine were determined using a polymerase chain reaction (PCR). Thirty-seven (37%) out of 100 S. aureus isolates were toxin gene positive. Four strains (10.8%) were sea-positive, 20 (54.1%) were seb-positive, 4 (10.8%) were sec-positive, 6 (16.2%) were sed-positive and 3 (8.1%) were see-positive. None of these enterotoxigenic isolates carried more than one toxin gene. This study indicates that the presence of enterotoxigenic S. aureus in raw milk can contribute to the sources of staphylococcal food poisoning in Palestine.