Displaying publications 1 - 20 of 29 in total

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  1. Shokryazdan P, Sieo CC, Kalavathy R, Liang JB, Alitheen NB, Faseleh Jahromi M, et al.
    Biomed Res Int, 2014;2014:927268.
    PMID: 25105147 DOI: 10.1155/2014/927268
    The objective of this study was to isolate, identify, and characterize some lactic acid bacterial strains from human milk, infant feces, and fermented grapes and dates, as potential probiotics with antimicrobial activity against some human pathogenic strains. One hundred and forty bacterial strains were isolated and, after initial identification and a preliminary screening for acid and bile tolerance, nine of the best isolates were selected and further identified using 16 S rRNA gene sequences. The nine selected isolates were then characterized in vitro for their probiotic characteristics and their antimicrobial activities against some human pathogens. Results showed that all nine isolates belonged to the genus Lactobacillus. They were able to tolerate pH 3 for 3 h, 0.3% bile salts for 4 h, and 1.9 mg/mL pancreatic enzymes for 3 h. They exhibited good ability to attach to intestinal epithelial cells and were not resistant to the tested antibiotics. They also showed good antimicrobial activities against the tested pathogenic strains of humans, and most of them exhibited stronger antimicrobial activity than the reference strain L. casei Shirota. Thus, the nine Lactobacillus strains could be considered as potential antimicrobial probiotic strains against human pathogens and should be further studied for their human health benefits.
    Matched MeSH terms: RNA, Bacterial/genetics
  2. Teramoto M, Queck SY, Ohnishi K
    PLoS One, 2013;8(6):e66594.
    PMID: 23824553 DOI: 10.1371/journal.pone.0066594
    Major degraders of petroleum hydrocarbons in tropical seas have been indicated only by laboratory culturing and never through observing the bacterial community structure in actual environments. To demonstrate the major degraders of petroleum hydrocarbons spilt in actual tropical seas, indigenous bacterial community in seawater at Sentosa (close to a port) and East Coast Park (far from a port) in Singapore was analyzed. Bacterial species was more diverse at Sentosa than at the Park, and the composition was different: γ-Proteobacteria (57.3%) dominated at Sentosa, while they did not at the Park. Specialized hydrocarbonoclastic bacteria (SHCB), which use limited carbon sources with a preference for petroleum hydrocarbons, were found as abundant species at Sentosa, indicating petroleum contamination. On the other hand, SHCB were not the abundant species at the Park. The abundant species of SHCB at Sentosa were Oleibacter marinus and Alcanivorax species (strain 2A75 type), which have previously been indicated by laboratory culturing as important petroleum-aliphatic-hydrocarbon degraders in tropical seas. Together with the fact that SHCB have been identified as major degraders of petroleum hydrocarbons in marine environments, these results demonstrate that the O. marinus and Alcanivorax species (strain 2A75 type) would be major degraders of petroleum aliphatic hydrocarbons spilt in actual tropical seas.
    Matched MeSH terms: RNA, Bacterial/genetics
  3. Hoe CH, Raabe CA, Rozhdestvensky TS, Tang TH
    Int J Med Microbiol, 2013 Jul;303(5):217-29.
    PMID: 23660175 DOI: 10.1016/j.ijmm.2013.04.002
    Bacteria are often exposed to a hostile environment and have developed a plethora of cellular processes in order to survive. A burgeoning list of small non-coding RNAs (sRNAs) has been identified and reported to orchestrate crucial stress responses in bacteria. Among them, cis-encoded sRNA, trans-encoded sRNA, and 5'-untranslated regions (UTRs) of the protein coding sequence are influential in the bacterial response to environmental cues, such as fluctuation of temperature and pH as well as other stress conditions. This review summarizes the role of bacterial sRNAs in modulating selected stress conditions and highlights the alliance between stress response and clustered regularly interspaced short palindromic repeats (CRISPR) in bacterial defense.
    Matched MeSH terms: RNA, Bacterial/genetics
  4. Koh SF, Tay ST, Sermswan R, Wongratanacheewin S, Chua KH, Puthucheary SD
    J Microbiol Methods, 2012 Sep;90(3):305-8.
    PMID: 22705921 DOI: 10.1016/j.mimet.2012.06.002
    We have developed a multiplex PCR assay for rapid identification and differentiation of cultures for Burkholderia pseudomallei, Burkholderia thailandensis, Burkholderia mallei and Burkholderia cepacia complex. The assay is valuable for use in clinical and veterinary laboratories, and in a deployable laboratory during outbreaks.
    Matched MeSH terms: RNA, Bacterial/genetics
  5. Vadivelu J, Puthucheary SD, Drasar BS, Dance DA, Pitt TL
    Trop Med Int Health, 1998 Jul;3(7):518-21.
    PMID: 9705184
    The constancy of strain genotypes of multiple isolates of Burkholderia pseudomallei from 13 patients with melioidosis was examined by BamHI ribotyping and pulsed-field gel electrophoresis (PFGE) of XbaI digests of DNA. Seven of 8 patients with single episodes of melioidosis each yielded genetically identical isolates and only one of five patients with recurrent episodes was infected with a new strain clearly distinct from the original primary strain. Variation was observed in PFGE patterns of primary and relapse isolates of another patient but this was insufficient to define genetically distinct strains. We conclude that most patients with single or multiple episodes of melioidosis retain a single strain.
    Matched MeSH terms: RNA, Bacterial/genetics
  6. Khoo JJ, Lim FS, Tan KK, Chen FS, Phoon WH, Khor CS, et al.
    J Med Entomol, 2017 09 01;54(5):1444-1448.
    PMID: 28874019 DOI: 10.1093/jme/tjx131
    Spirochetes from the Borrelia genus are known to cause diseases in humans, namely Lyme disease and relapsing fever. These organisms are commonly transmitted to humans by arthropod vectors including ticks, mite, and lice. Here, we report the molecular detection of a Borrelia sp. from a Haemaphysalis hystricis Supino tick collected from wildlife in an Orang Asli settlement in Selangor, Malaysia. Phylogenetic analyses of partial 16s rRNA and flaB gene sequences revealed that the Borrelia sp. is closely related to the relapsing fever group borreliae, Borrelia lonestari, Borrelia miyamotoi, and Borrelia theileri, as well as a number of uncharacterized Borrelia sp. from ticks in Portugal and Japan. To our knowledge, this is the first report of a Borrelia sp. detected in H. hystricis, and in Malaysia. The zoonotic potential of this Borrelia sp. merits further investigation.
    Matched MeSH terms: RNA, Bacterial/genetics
  7. Miyashita NT
    Genes Genet Syst, 2015;90(2):61-77.
    PMID: 26399766 DOI: 10.1266/ggs.90.61
    Soil bacterial community structures of six dominant phyla (Acidobacteria, Proteobacteria, Verrucomicrobia, Planctomycetes, Bacteroidetes and Actinobacteria) and unclassified bacteria detected in tropical Sarawakian and temperate Japanese forests were compared based on 16S rRNA gene sequence variation. The class composition in each phylum was similar among the studied forests; however, significant heterogeneities of class frequencies were detected. Acidobacteria and Proteobacteria were the most dominant phyla in all six forests, but differed in the level of bacterial species diversity, pattern of species occurrence and association pattern of species composition with physicochemical properties in soil. Species diversity among Acidobacteria was approximately half that among Proteobacteria, based on the number of clusters and the Chao1 index, even though a similar number of sequence reads were obtained for these two phyla. In contrast, species diversity within Planctomycetes and Bacteroidetes was nearly as high as within Acidobacteria, despite many fewer sequence reads. The density of species (the number of sequence reads per cluster) correlated negatively with species diversity, and species density within Acidobacteria was approximately twice that within Proteobacteria. Although the percentage of forest-specific species was high for all bacterial groups, sampling site-specific species varied among bacterial groups, indicating limited inter-forest migration and differential movement of bacteria in forest soil. For five of the seven bacterial groups, including Acidobacteria, soil pH appeared to strongly influence species composition, but this association was not observed for Proteobacterial species. Topology of UPGMA trees and pattern of NMDS plots among the forests differed among the bacterial groups, suggesting that each bacterial group has adapted and evolved independently in each forest.
    Matched MeSH terms: RNA, Bacterial/genetics
  8. Ahmed SA, Raabe CA, Cheah HL, Hoe CH, Rozhdestvensky TS, Tang TH
    Am J Trop Med Hyg, 2019 Jun;100(6):1328-1334.
    PMID: 30963989 DOI: 10.4269/ajtmh.18-0525
    The diarrheal disease "cholera" is caused by Vibrio cholerae, and is primarily confined to endemic regions, mostly in Africa and Asia. It is punctuated by outbreaks and creates severe challenges to public health. The disease-causing strains are most-often members of serogroups O1 and O139. PCR-based methods allow rapid diagnosis of these pathogens, including the identification of their biotypes. However, this necessitates the selection of specific target sequences to differentiate even the closely related biotypes of V. cholerae. Oligonucleotides for selective amplification of small RNA (sRNA) genes that are specific to these V. cholerae subtypes were designed. The resulting multiplex PCR assay was validated using V. cholerae cultures (i.e., 19 V. cholerae and 22 non-V. cholerae isolates) and spiked stool samples. The validation using V. cholerae cultures and spiked stool suspensions revealed detection limits of 10-100 pg DNA per reaction and 1.5 cells/mL suspension, respectively. The multiplex PCR assay that targets sRNA genes for amplification enables the sensitive and specific detection, as well as the differentiation of V. cholerae-O1 classical, O1 El Tor, and O139 biotypes. Most importantly, the assay enables fast and cheaper diagnosis compared with classic culture-based methods.
    Matched MeSH terms: RNA, Bacterial/genetics*
  9. Ten KE, Rahman S, Tan HS
    Microb Genom, 2024 Nov;10(11).
    PMID: 39565092 DOI: 10.1099/mgen.0.001327
    Despite being a major human pathogen, limited studies have reported RNA modifications in Acinetobacter baumannii. These post-transcriptional modifications play crucial regulatory roles in bacteria and have also been shown to modulate bacterial virulence. Using nanopore sequencing, we characterized RNA modifications in a virulent A. baumannii strain (Ab-C98) under free-living (mid-exponential phase in vitro culture) and during an early stage of infection (3 h post-infection) in Galleria mellonella larvae. Analysis revealed that m5C methylations are essential for ribosome synthesis, while m6A and Ψ are involved in metabolic pathways and translation processes. Iron-chelating genes exbD (m5C and m6A) and feoB (m6A and Ψ) and RNA polymerase subunit rpoC (m6A and Ψ) were selectively modified during infection. This first transcriptome-wide study highlights the potential regulatory roles of m5C, m6A and Ψ modifications in A. baumannii during infection.
    Matched MeSH terms: RNA, Bacterial/genetics
  10. Tan CG, Ideris A, Omar AR, Yii CP, Kleven SH
    Onderstepoort J Vet Res, 2014 09 02;81(1):e1-e7.
    PMID: 25686255 DOI: 10.4102/ojvr.v81i1.708
    The present study was based on the reverse transcription polymerase chain reaction (RT-PCR) of the 16S ribosomal nucleic acid (rRNA) of Mycoplasma for detection of viable Mycoplasma gallisepticum. To determine the stability of M. gallisepticum 16S rRNA in vitro, three inactivation methods were used and the suspensions were stored at different temperatures. The 16S rRNA of M. gallisepticum was detected up to approximately 20-25 h at 37 °C, 22-25 h at 16 °C, and 23-27 h at 4 °C. The test, therefore, could detect viable or recently dead M. gallisepticum (< 20 h). The RT-PCR method was applied during an in vivo study of drug efficacy under experimental conditions, where commercial broiler-breeder eggs were inoculated with M. gallisepticum into the yolk. Hatched chicks that had been inoculated in ovo were treated with Macrolide 1. The method was then applied in a flock of day 0 chicks with naturally acquired vertical transmission of M. gallisepticum, treated with Macrolide 2. Swabs of the respiratory tract were obtained for PCR and RT-PCR evaluations to determine the viability of M. gallisepticum. This study proved that the combination of both PCR and RT-PCR enables detection and differentiation of viable from non-viable M. gallisepticum.
    Matched MeSH terms: RNA, Bacterial/genetics
  11. Zakaria Z, Radu S, Sheikh-Omar AR, Mutalib AR, Joseph PG, Rusul G
    Vet Microbiol, 1998 Jul;62(3):243-50.
    PMID: 9791871
    Pulsed field gel electrophoresis analysis of genomic DNA was used to investigate genetic diversity among Dichelobacter nodosus from footrot in sheep in Malaysia. Twelve Dichelobacter nodosus strains isolated from lesion materials from infected sheep were confirmed as Dichelobacter nodosus by polymerase chain reaction technique using the species-specific Dichelobacter nodosus 16S RNA sequence Ac and C as primers. Pulsed field gel electrophoresis banding profiles using restriction enzymes ApaI (5'GGGCCC3'), SfiI (5'GGCCNNNNNGGCC3') and SmaI ('5CCCGGG3') enabled the 12 Dichelobacter nodosus strains to be differentiated into eight different PFGE patterns and thus genome-types, with F (coefficient of similarity) values ranging from 0.17 to 1.0 (ApaI), 0.14 to 1.0 (SfiI) and 0.22 to 1.0 (SmaI). Strains with origin in different farms were shown to have different PFGE patterns (two strains, M7 and M8 were the only exception). On the basis of their PFGE, all field strains used in the study differed from the reference strains. Our data revealed that there are several clonal types of Dichelobacter nodosus isolates and indicated that there is probably more than one source of this pathogen on the farms studied. The study showed that strains of D. nodosus exhibited considerable genetic diversity using this method and that genomic analysis by pulsed field gel electrophoresis was useful in discriminating the D. nodosus strains.
    Matched MeSH terms: RNA, Bacterial/genetics
  12. Jackson CR, Liew KC, Yule CM
    Microb Ecol, 2009 Apr;57(3):402-12.
    PMID: 18548182 DOI: 10.1007/s00248-008-9409-4
    Tropical peat swamp forests are important and endangered ecosystems, although little is known of their microbial diversity and ecology. We used molecular and enzymatic techniques to examine patterns in prokaryotic community structure and overall microbial activity at 0-, 10-, 20-, and 50-cm depths in sediments in a peat swamp forest in Malaysia. Denaturing gradient gel electrophoresis profiles of amplified 16S ribosomal ribonucleic acid (rRNA) gene fragments showed that different depths harbored different bacterial assemblages and that Archaea appeared to be limited to the deeper samples. Cloning and sequencing of longer 16S rRNA gene fragments suggested reduced microbial diversity in the deeper samples compared to the surface. Bacterial clone libraries were largely dominated by ribotypes affiliated with the Acidobacteria, which accounted for at least 27-54% of the sequences obtained. All of the sequenced representatives from the archaeal clone libraries were Crenarchaeota. Activities of microbial extracellular enzymes involved in carbon, nitrogen, and phosphorus cycling declined appreciably with depth, the only exception being peroxidase. These results show that tropical peat swamp forests are unusual systems with microbial assemblages dominated by members of the Acidobacteria and Crenarchaeota. Microbial communities show clear changes with depth, and most microbial activity is likely confined to populations in the upper few centimeters, the site of new leaf litter fall, rather than the deeper, older, peat layers.
    Matched MeSH terms: RNA, Bacterial/genetics
  13. Jong BC, Liew PW, Lebai Juri M, Kim BH, Mohd Dzomir AZ, Leo KW, et al.
    Lett Appl Microbiol, 2011 Dec;53(6):660-7.
    PMID: 21967346 DOI: 10.1111/j.1472-765X.2011.03159.x
    To evaluate the bioenergy generation and the microbial community structure from palm oil mill effluent using microbial fuel cell.
    Matched MeSH terms: RNA, Bacterial/genetics
  14. Noman AE, Al-Barha NS, Sharaf AM, Al-Maqtari QA, Mohedein A, Mohammed HHH, et al.
    Sci Rep, 2020 08 11;10(1):13527.
    PMID: 32782276 DOI: 10.1038/s41598-020-70404-4
    A novel bacterial strain of acetic acid bacteria capable of producing riboflavin was isolated from the soil sample collected in Wuhan, China. The isolated strain was identified as Gluconobacter oxydans FBFS97 based on several phenotype characteristics, biochemicals tests, and 16S rRNA gene sequence conducted. Furthermore, the complete genome sequencing of the isolated strain has showed that it contains a complete operon for the biosynthesis of riboflavin. In order to obtain the maximum concentration of riboflavin production, Gluconobacter oxydans FBFS97 was optimized in shake flask cultures through response surface methodology employing Plackett-Burman design (PBD), and Central composite design (CCD). The results of the pre-experiments displayed that fructose and tryptone were found to be the most suitable sources of carbon and nitrogen for riboflavin production. Then, PBD was conducted for initial screening of eleven minerals (FeSO4, FeCl3, KH2PO4, K2HPO4, MgSO4, ZnSO4, NaCl, CaCl2, KCl, ZnCl2, and AlCl3.6H2O) for their significances on riboflavin production by Gluconobacter oxydans strain FBFS97. The most significant variables affecting on riboflavin production are K2HPO4 and CaCl2, the interaction affects and levels of these variables were optimized by CCD. After optimization of the medium compositions for riboflavin production were determined as follows: fructose 25 g/L, tryptone 12.5 g/L, K2HPO4 9 g/L, and CaCl2 0.06 g/L with maximum riboflavin production 23.24 mg/L.
    Matched MeSH terms: RNA, Bacterial/genetics
  15. Zong Z, Wang X, Deng Y, Zhou T
    J Med Microbiol, 2012 Oct;61(Pt 10):1483-1484.
    PMID: 22820689 DOI: 10.1099/jmm.0.041525-0
    A previously healthy Chinese male returned from working in the Malaysian jungle with a fever. A blood culture grew Gram-negative bacilli that were initially identified as Burkholderia cepacia by the VITEK 2 system but were subsequently found to be Burkholderia pseudomallei by partial sequencing of the 16S rRNA gene. The identification of B. pseudomallei using commercially available automated systems is problematic and clinicians in non-endemic areas should be aware of the possibility of melioidosis in patients with a relevant travel history and blood cultures growing Burkholderia spp.
    Matched MeSH terms: RNA, Bacterial/genetics
  16. Choo SW, Wong YL, Leong ML, Heydari H, Ong CS, Ng KP, et al.
    J Bacteriol, 2012 Oct;194(20):5724.
    PMID: 23012295
    Mycobacterium abscessus is a species of rapidly growing nontuberculous mycobacteria that is frequently associated with opportunistic infections in humans. Here, we report the annotated genome sequence of M. abscessus strain M94, which showed an unusual cluster of tRNAs.
    Matched MeSH terms: RNA, Bacterial/genetics
  17. Sariyati NH, Othman N, Abdullah-Fauzi NAF, Chan E, Md-Zain BM, Karuppannan KV, et al.
    J Med Primatol, 2024 Oct;53(5):e12730.
    PMID: 39148344 DOI: 10.1111/jmp.12730
    BACKGROUND: The gut morphology of Symphalangus syndactylus exhibits an intermediate structure that aligns with its consumption of fruit and ability to supplement its diet with leaves. The Siamang relies on its gut microbiome for energy extraction, immune system development, and the synthesis of micronutrients. Gut microbiome composition may be structured based on several factors such as age, sex, and habitat. No study has yet been carried out on the gut microbiota of the Hylobatidae members in Malaysia especially S. syndactylus.

    METHODS: This study aims to resolve the gut microbiome composition of S. syndactylus by using a fecal sample as DNA source, adapting high-throughput sequencing, and 16S rRNA as the targeted region.

    RESULTS: A total of 1 272 903 operational taxonomic units (OTUs) reads were assigned to 22 phyla, 139 families, and 210 genera of microbes. The {Unknown Phylum} Bacteria-2 is the dominant phyla found across all samples. Meanwhile, {Unknown Phylum} Bacteria-2 and Firmicutes are genera that have the highest relative abundance found in the Siamang gut.

    CONCLUSIONS: This study yields nonsignificance relationship between Siamang gut microbiome composition with these three factors: group, sex, and age.

    Matched MeSH terms: RNA, Bacterial/genetics
  18. Song AA, Abdullah JO, Abdullah MP, Shafee N, Othman R, Noor NM, et al.
    FEMS Microbiol Lett, 2014 Jun;355(2):177-84.
    PMID: 24828482 DOI: 10.1111/1574-6968.12469
    Isoprenoids are a large, diverse group of secondary metabolites which has recently raised a renewed research interest due to genetic engineering advances, allowing specific isoprenoids to be produced and characterized in heterologous hosts. Many researches on metabolic engineering of heterologous hosts for increased isoprenoid production are focussed on Escherichia coli and yeasts. E. coli, as most prokaryotes, use the 2-C-methyl-d-erythritol-4-phosphate (MEP) pathway for isoprenoid production. Yeasts on the other hand, use the mevalonate pathway which is commonly found in eukaryotes. However, Lactococcus lactis is an attractive alternative host for heterologous isoprenoid production. Apart from being food-grade, this Gram-positive prokaryote uses the mevalonate pathway for isoprenoid production instead of the MEP pathway. Previous studies have shown that L. lactis is able to produce sesquiterpenes through heterologous expression of plant sesquiterpene synthases. In this work, we analysed the gene expression of the lactococcal mevalonate pathway through RT-qPCR to successfully engineer L. lactis as an efficient host for isoprenoid production. We then overexpressed the mvk gene singly or co-expressed with the mvaA gene as an attempt to increase β-sesquiphellandrene production in L. lactis. It was observed that co-expression of mvk with mvaA doubled the amount of β-sesquiphellandrene produced.
    Matched MeSH terms: RNA, Bacterial/genetics
  19. Atshan SS, Shamsudin MN, Karunanidhi A, van Belkum A, Lung LT, Sekawi Z, et al.
    Infect Genet Evol, 2013 Aug;18:106-12.
    PMID: 23669446 DOI: 10.1016/j.meegid.2013.05.002
    Staphylococcus aureus biofilm associated infections remains a major clinical concern in patients with indwelling devices. Quantitative real-time PCR (qPCR) can be used to investigate the pathogenic role of such biofilms. We describe qPCRs for 12 adhesion and biofilm-related genes of four S. aureus isolates which were applied during in vitro biofilm development. An endogenous control (16S rRNA) was used for signal normalization. We compared the qPCR results with structural analysis using scanning electron microscopy (SEM). The SEM studies showed different cellular products surrounding the aggregated cells at different times of biofilm formation. Using qPCR, we found that expression levels of the gene encoding fibronectin binding protein A and B and clumping factor B (fnbA/B and clfB), which involves in primary adherence of S. aureus, were significantly increased at 24h and decreased slightly and variably at 48 h when all 4 isolates were considered. The elastin binding protein (ebps) RNA expression level was significantly enhanced more than 6-fold at 24 and 48 h compared to 12h. Similar results were obtained for the intercellular adhesion biofilm required genes type C (icaC). In addition, qPCR revealed a fluctuation in expression levels at different time points of biofilm growth of other genes, indicating that different parameter modes of growth processes are operating at different times.
    Matched MeSH terms: RNA, Bacterial/genetics
  20. Khoo JJ, Lim FS, Chen F, Phoon WH, Khor CS, Pike BL, et al.
    Vector Borne Zoonotic Dis, 2016 12;16(12):744-751.
    PMID: 27763821
    Recent studies have shown that ticks harbor Coxiella-like bacteria, which are potentially tick-specific endosymbionts. We recently described the detection of Coxiella-like bacteria and possibly Coxiella burnetii in ticks found from rural areas in Malaysia. In the present study, we collected ticks, including Haemaphysalis bispinosa, Haemaphysalis hystricis, Dermacentor compactus, Dermacentor steini, and Amblyomma sp. from wildlife and domesticated goats from four different locations in Malaysia. Coxiella 16s rRNA genomic sequences were detected by PCR in 89% of ticks tested. Similarity analysis and phylogenetic analyses of the 16s rRNA and rpoB partial sequences were performed for 10 representative samples selected based on the tick species, sex, and location. The findings here suggested the presence of C. burnetii in two samples, each from D. steini and H. hystricis. The sequences of both samples clustered with published C. burnetii sequences. The remaining eight tick samples were shown to harbor 16s rRNA sequences of Coxiella-like bacteria, which clustered phylogenetically according to the respective tick host species. The findings presented here added to the growing evidence of the association between Coxiella-like bacteria and ticks across species and geographical boundaries. The importance of C. burnetii found in ticks in Malaysia warrants further investigation.
    Matched MeSH terms: RNA, Bacterial/genetics
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