The mazEF toxin-antitoxin system as a novel antibacterial target in Acinetobacter baumannii

Although analysis of toxin-antitoxin (TA) systems can be instructive, to date, there is no information on the prevalence and identity of TA systems based on a large panel of Acinetobacter baumannii clinical isolates. The aim of the current study was to screen for functional TA systems among clinical isolates of A. baumannii and to identify the systems' locations. For this purpose, we screened 85 A. baumannii isolates collected from different clinical sources for the presence of the mazEF, relBE and higBA TA genes. The results revealed that the genes coding for the mazEF TA system were commonly present in all clinical isolates of A. baumannii. Reverse transcriptase-polymerase chain reaction analysis showed that transcripts were produced in the clinical isolates. Our findings showed that TA genes are prevalent, harboured by chromosomes and transcribed within A. baumannii. Hence, activation of the toxin proteins in the mazEF TA system should be investigated further as an effective antibacterial strategy against this bacterium

Molecular Detection of Strongyloides ratti in Faecal Samples from Wild Rats in Serdang, Malaysia

Purpose: To detect Strongyloides ratti in faecal samples using conventional methods and to confirm the identification using a sensitive and specific method, namely, polymerase chain reaction (PCR).Methods: A PCR method targeting the small subunit of the rRNA gene was performed in this study for the detection of DNA from Strongyloides ratti (an animal model of S. stercoralis) in faecal samples of wild Brown rats, Rattus norvegicus.Results: Strongyloides ratti was detected in 34.2 % of collected rats by different conventional techniques and confirmed by PCR. The essay presented 100 % sensitivity with Strongyloides universal primer.Conclusion: The findings of this study suggest that the application of PCR with universal primer is a very sensitive methodology to detect S. ratti in faecal material of wild rats infected even with very low parasite burden.Keywords: Faecal, Parasite, Strongyloides stercoralis, Strongyloides ratti, Brown Rat, DNA, Universal prime

Wide Distribution of Virulence Genes among Enterococcus faecium and Enterococcus faecalis Clinical Isolates

Enterococcus, a Gram-positive facultative anaerobic cocci belonging to the lactic acid bacteria of the phylum Firmicutes, is known to be able to resist a wide range of hostile conditions such as different pH levels, high concentration of NaCl (6.5), and the extended temperatures between 5 degrees C and 65 degrees C. Despite being the third most common nosocomial pathogen, our understanding on its virulence factors is still poorly understood. The current study was aimed to determine the prevalence of different virulence genes in Enterococcus faecalis and Enterococcus faecium. For this purpose, 79 clinical isolates of Malaysian enterococci were evaluated for the presence of virulence genes. pilB, fms8, efaAfm, and sgrA genes are prevalent in all clinical isolates. In conclusion, the pathogenicity of E. faecalis and E. faecium could be associated with different virulence factors and these genes are widely distributed among the enterococcal species

Differential between multi-drug resistance pattern of extended spectrum β-lactamases producing E. coli and K. pneumoniae

The current study aimed to determine the prevalence of Extended-Spectrum β-Lactamases (ESBLs) in Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) strains isolated from patients with Urinary Tract Infections (UTIs), to study the association between presence of ESBL enzyme and multi-drug resistance strains and finally, and to investigate the predominant ESBL gene in E. coli and K. pneumoniae. The strains were examined for the presence of ESBL as a Clinical Laboratory Standards Institute (CLSI) guideline. Among 284 clinical isolates, 52.8 (n = 150) and 47.2 (n =134) were E. coli and K. pneumoniae, respectively, and 110 strains were ESBL producer, which 68 strains were K. pneumoniae and 42 strains were E. coli. Significant difference observed between the TEM gene and ciprofloxacin resistant in E. coli (P ≤ 0.05) while no significant difference observed between CTX-M, SHV genes and the other multi-drug resistant E. coli. No significant difference observed between CTX-M, TEM, and SHV genes and multi-drug resistant K. pneumoniae. In conclusion, spreading of ESBL-producing strains is a concern, as it causes limitations to the antimicrobial agents for optimal treatment of patients. Prevalence of ESBLs was more observed in K. pneumoniae than E. coli. In addition, TEM gene was more prevalent in E. coli and resistance to ciprofloxacin was predominant in E. coli

Kualiti guru berasaskan Al-Ghazali: Ke arah Kecemerlangan pendidikan masa depan

Profesion keguruan merupakan kerjaya yang semakin mencabar dewasa ini. Golongan guru sering menjadi perhatian masyarakat umum kerana guru adalah aktor yang amat penting dalam usaha mencapai kecemerlangan pendidikan masa depan. Cabaran dengan sikap pelajar yang semakin tidak beradab, sikap ibubapa yang lebihn agresif, cabaran sebagai role model dan sebagainya memerlukan guru menyediakan diri mereka sebagai seorang guru yang berkualiti dalam menangani masalah ini. Terdapat pelbagai teori berkaitan kualiti guru yang diketengahkan oleh pengkaji terdahulu, bagaimanapun teori khusus berasakan al-Ghazali belum diketengaahkan secara spesifik. Justeru, kertas kerja ini mendedahkan tentang teori kualiti guru yang diubahsuai oleh penulis bersumberkan karya al-Ghazali dalam Ihya’ Ulumuddin. Terdapat empat aspek kualiti yang dibincangkan dalam kertas kerja ini iaitu penguasaan kaedah, pengetahuan isi kandungan mata pelajaran, kualiti dalam komunikasi dan kualiti dalam penampilan diri di dalam bilik darjah

Survival of antibiotic resistant escherichia coli in vacuum-packed keropok lekor: food safety alert among sme keropok lekor producers

The microbiological quality of thirty ready-to-eat (RTE) keropok lekor (a sausage shape Malaysian fish product) was evaluated in comparison to microbiological guidelines for ready to eat foods. The two E. coli isolates were subjected to DNA sequencing, identified and tested for their resistance towards fifteen different antibiotics. The survival and growth of the isolated E. coli strains inoculated in keropok lekor at atmospheric air and vacuum packaging were also evaluated. Results revealed that four samples (13.33%) contained Enterobacteriaceae counts that exceeded the recommended allowable counts of 4.0 log10 CFU/g. Unsatisfactory level of coliforms (> 1.7 log10 CFU/g) was also observed in ten of the samples; two of which contained E. coli (2.1 ± 0.17 and 3.7 ± 0.02 log10 CFU/g), suggesting of poor hygiene and sanitation practices. While the ‘Possible E10’ E. coli strain was observably resistant towards Nalidixic acid (30µg) alone, B10 E. coli isolate was worryingly resistant towards Ampicillin (10µg), Ceftazidime (30µg), Ciprofloxacin (5µg), Ceftriaxone (30µg), Nalidixic acid (30µg) and Tetracycline (30µg). This study also revealed that the growth and survival of the ‘Possible E10’ and B10 E. coli strains were not significantly affected by vacuum packaging when stored at both 4°C and 28°C. Therefore, intervention programmes to alert and educate small-medium enterprisers (SMEs) of keropok lekor producers on food safety as well as potential health risks that can be associated due to inappropriate handling procedures of such product, merits consideration

The mazEF toxin–antitoxin system as an attractive target in clinical isolates of Enterococcus faecium and Enterococcus faecalis

Sara Soheili,1 Sobhan Ghafourian,2 Zamberi Sekawi,1 Vasantha Kumari Neela,1 Nourkhoda Sadeghifard,2 Morovat Taherikalani,2 Afra Khosravi,2 Ramliza Ramli,3 Rukman Awang Hamat11Department of Medical Microbiology and Parasitology, Faculty of Medicine and Health sciences, Universiti Putra Malaysia, Serdang, Malaysia; 2Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran; 3Department of Medical Microbiology and Immunology, Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Centre, Jalan Yaakob Latif, Bandar Tun Razak, Kuala Lumpur, Malaysia Abstract: The toxin–antitoxin (TA) system is a regulatory system where two sets of genes encode the toxin and its corresponding antitoxin. In this study, the prevalence of TA systems in independently isolated clinical isolates of Enterococcus faecium and Enterococcus faecalis was determined, the dominant TA system was identified, different virulence genes in E. faecium and E. faecalis were surveyed, the level of expression of the virulence and TA genes in normal and stress conditions was determined, and finally their associations with the TA genes were defined. Remarkably, the analysis demonstrated higBA and mazEF in all clinical isolates, and their locations were on chromosomes and plasmids, respectively. On the other hand, a quantitative analysis of TA and virulence genes revealed that the expression level in both genes is different under normal and stress conditions. The results obtained by anti-mazF peptide nucleic acids demonstrated that the expression level of virulence genes had decreased. These findings demonstrate an association between TA systems and virulence factors. The mazEF on the plasmids and the higBA TA genes on the chromosomes of all E. faecium and E. faecalis strains were dominant. Additionally, there was a decrease in the expression of virulence genes in the presence of anti-mazF peptide nucleic acids. Therefore, it is suggested that mazEF TA systems are potent and sensitive targets in all E. faecium and E. faecalis strains.Keywords: Enterococcus faecium, Enterococcus faecalis, toxin–antitoxin system, virulence genes, peptide nucleic acid

Methicillin-susceptible Staphylococcus aureus from clinical and community sources are genetically diverse

Despite the association of methicillin-susceptible S. aureus (MSSA) with several life-threatening diseases, relatively little is known about their clinical epidemiology in Malaysia. We characterized MSSA isolates (n = 252) obtained from clinical and community (carriage) sources based on spa sequencing and multilocus sequence typing (MLST). The prevalence of several important virulence genes was determined to further define the molecular characteristics of MSSA clones circulating in Malaysia. Among the 142 clinical and 110 community-acquired MSSA isolates, 98 different spa types were identified, corresponding to 8 different spa clonal clusters (spa-CCs). In addition, MLST analysis revealed 22 sequence types (STs) with 5 singletons corresponding to 12 MLST-CCs. Interestingly, spa-CC084/085 (MLST-CC15) (p = 0.038), spa-non-founder 2 (MLST-ST188) (p = 0.002), and spa-CC127 (MLST-CC1) (p = 0.049) were identified significantly more often among clinical isolates. spa-CC3204 (MLST-CC121) (p = 0.02) and spa-CC015 (MLST-CC45) (p = 0.0002) were more common among community isolates. Five dominant MLST-CCs (CC8, CC121, CC1, CC45, and CC5) having clear counterparts among the major MRSA clones were also identified in this study. While the MSSA strains are usually genetically heterogeneous, a relatively high frequency (19/7.5%) of ST188 (t189) strains was found, with 57.8% of these strains carrying the Panton-Valentine leukocidin (PVL). Analysis of additional virulence genes showed a frequency of 36.5% and 36.9% for seg and sei and 0.8% and 6.3% for etb and tst genes, respectively. Arginine catabolic mobile element (ACME) was detected in 4 community isolates only. These represent the first isolates harbouring this gene in an Asian region. In conclusion, MSSA from the Malaysian community and their clinical counterparts are genetically diverse, but certain clones occur more often among clinical isolates than among carriage isolates and vice versa. (C) 2010 Elsevier GmbH. All rights reserved