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The continuous escalation of resistant bacteria against a wide range of antibiotics necessitates discovering novel unconventional sources of antibiotics. B. oleracea L (red cabbage) is health-promoting food with proven anticancer and anti-inflammatory activities. However, it has not been researched adequately for its antimicrobial activity on potential resistant pathogens. The methanol crude extract of B. oleracea L. was investigated for a possible anti-microbial activity. The screening method was conducted using disc diffusion assay against 22 pathogenic bacteria and fungi. It was followed by evaluation of the minimum inhibitory concentration (MIC). Moreover, the antibacterial and the antifungal activities were confirmed using the minimum bactericidal concentration (MBC) and the minimum fungicidal concentration (MFC), respectively. Remarkable, antibacterial activity was evident particularly against highly infectious microorganisms such as Methicillin-resistant Staphylococcus aureus, Escherichia coli O157:H7, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Salmonella enterica serovar Typhimurium as well as against human fungal pathogens, Trichophyton rubrum and Aspergillus terreus. Red cabbage is a rich source of phenolic compounds, anthocyanins being the most abundant class, which might explain its potent antimicrobial action. This extract is potentially novel for future antimicrobials, inexpensive, and readily available at a large scale for pharmaceutical companies for further investigation and processing.

Despite all efforts, there is still no effective vaccine available against the human respiratory syncytial virus (HRSV) that is a major cause of severe lower respiratory tract disease in infants and the elderly. In this review, we examined the potential of the conserved immunogenic region (residues 122-226) of the HRSV glycoprotein G alone as the inducer of neutralizing antibodies against this virus. The Escherichia coli produced recombinant conserved region of G (designated as G domain), which was used for rabbit immunization. Although rabbit is semipermissive host for HRSV, our result showed that the polyclonal antibodies against the G domain protein could strongly neutralize the virus (69.3), suggesting that the G immunogenic region of HRSV alone has a great potential in vaccine development. To our knowledge, this is the first report in which neutralizing antibodies to respiratory syncytial virus have been evoked using bacterially expressed G immunogenic domain protein without any adjuvant. (C) 2011 International Union of Biochemistry and Molecular Biology, Inc. Volume 58, Number 2, March/April 2011, Pages 97-102. E-mail: kyusoff@biotech.upm.edu.my

The H5 gene of avian influenza virus (AIV) strain A/chicken/Malaysia/5744/2004(H5N1) was cloned into pcDNA3.1 vector, and Esat-6 gene of Mycobacterium tuberculosis was fused into downstream of the H5 gene as a genetic adjuvant for DNA vaccine candidates. The antibody level against AIV was measured using enzyme-linked immunosorbent assay (ELISA) and haemagglutination inhibition (HI) test. Sera obtained from specific-pathogen-free chickens immunized with pcDNA3.1/H5 and pcDNA3.1/H5/Esat-6 demonstrated antibody responses as early as 2 weeks after the first immunization. Furthermore, the overall HI antibody titer in chickens immunized with pcDNA3.1/H5/Esat-6 was higher compared to the chickens immunized with pcDNA3.1/H5 (p < 0.05). The results suggested that Esat-6 gene of M. tuberculosis is a potential genetic adjuvant for the development of effective H5 DNA vaccine in chickens.

Aims: A system for displaying heterologous respiratory syncytial virus (RSV) glycoproteins on the surface of Lactococcus lactis NZ9000 was developed. Methods and Results: Fusion of the USP45 signal peptide and the cA (C terminus of the peptidoglycan-binding) domains of AcmA, a major autolysin from L. lactis, to the N- and C-terminal of the target proteins, respectively, was carried out. The target protein was the major immunogenic domain of either the F (40·17-kDa) or G (11·49-kDa) glycoprotein domains of the RSV. Whole-cell ELISA readings obtained after 24 h of induction showed an increase in protein expression as the cA domain repeats increased, for the G glycoprotein of RSV. On the other hand, the F glycoprotein indicated decreasing expression levels as the number of cA domain repeats increased. The difference in the expression levels of the F and G domains may be attributed to the different sizes of the antigenic domains. Conclusions: The size and properties of the target proteins are vital in determining the amount of antigenic domains being displayed on the surface of live cells. Significance and Impact of the Study: The system demonstrated here can aid in the utilization of the generally regarded as safe (GRAS) bacteria L. lactis, as a vaccine delivery vehicle to surface display the antigenic proteins of RSV.

Methicillin-resistant Staphylococcus aureus (MRSA) is a nosocomial pathogen of increasing risk on community. This study aims at determining the risk of MRSA transfer from coins as silent and underestimated reservoir in community. One hundred swabs from coins were collected from college students in Malaysia. A series of identification and differentiating tests were conducted for precise identification of MRSA bacteria. Moreover, this study compared the efficacy of the different identification tests with gold standard, polymerase chain reaction (PCR) assay. The tests used were tube coagulase, DNase agar test, antibiogram, several routine biochemical identification tests and PCR assays. PCR assay used specific primers for resistance or ID -related genes: mecA, ermA, ermB, ermC, msrA, linA, femA, and nuc genes. A total of 37 bacterial isolates were isolated from college students’ coins; non-PCR assays of identification and resistance detection revealed the presence and spread of MRSA in coins of 2 college students. PCR-amplification of the nuc gene was used as a baseline test to detect S. aureus. PCR showed only one isolate as true MRSA. False positive MRSA by disc diffusion assay might be attributed to low pH and high thymidine content of Muller Hinton agar medium. Collectively, coins proved to be possible source for the transfer of MRSA in community of college students in South East Asia. Moreover, PCR assay for identification of S. aureus resistance proved to be superior on other methods. Key words : Staphylococcus aureus , MRSA, nail, PCR, resistance.

Allium hirtifoliumBoiss. known as Persian shallot, is a spice used as a traditional medicine in Iran and, Mediterranean region. In this study, the chemical composition of the hydromethanolic extract of this plant was analyzed using GC/MS. The result showed that 9-hexadecenoic acid, 11,14-eicosadienoic acid, and n-hexadecanoic acid are the main constituents. The antibacterial activity of the shallot extract was also examined by disk diffusion and microdilution broth assays. It was demonstrated that Persian shallot hydromethanolic extract was effective against 10 different species of pathogenic bacteria including methicillin resistantStaphylococcus aureus(MRSA), methicillin sensitiveStaphylococcus aureus(MSSA),Staphylococcus aureus,Staphylococcus epidermidis,Streptococcus pneumoniae,Escherichia coli, Escherichia coliO157:H7,Salmonella typhimurium, Proteus mirabilis, andKlebsiella pneumoniae. Specifically, the minimum concentration of the extract which inhibited bacterial growth (MIC values) was 1.88 mg/mL for most of the gram-positive bacteria. This concentration was not much different from the concentration that was safe for mammalian cells (1.50 mg/mL) suggesting that the hydromethanolic extract of Persian shallot may be a safe and strong antibacterial agent.

Background Avian influenza viruses (AIV) cause high morbidity and mortality among the poultry worldwide. Their highly mutative nature often results in the emergence of drug resistant strains, which have the potential of causing a pandemic. The virus has two immunologically important glycoproteins, hemagglutinin (HA), neuraminidase (NA), and one ion channel protein M2 which are the most important targets for drug discovery, on its surface. In order to identify a peptide-based virus inhibitor against any of these surface proteins, a disulfide constrained heptapeptide phage display library was biopanned against purified AIV sub-type H9N2 virus particles. Results After four rounds of panning, four different fusion phages were identified. Among the four, the phage displaying the peptide NDFRSKT possessed good anti-viral properties in vitro and in ovo. Further, this peptide inhibited the hemagglutination activity of the viruses but showed very little and no effect on neuraminidase and hemolytic activities respectively. The phage-antibody competition assay proved that the peptide competed with anti-influenza H9N2 antibodies for the binding sites. Based on yeast two-hybrid assay, we observed that the peptide inhibited the viral replication by interacting with the HA protein and this observation was further confirmed by co-immunoprecipitation. Conclusion Our findings show that we have successfully identified a novel antiviral peptide against avian influenza virus H9N2 which act by binding with the hemagglutination protein of the virus. The broad spectrum activity of the peptide molecule against various subtypes of the avian and human influenza viruses and its comparative efficiency against currently available anti-influenza drugs are yet to be explored.