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  1. Fulltext Multiplex APLP System for High-Resolution Haplogrouping of Extremely Degraded East-Asian Mitochondrial DNAs
    Kakuda T, Shojo H, Tanaka M, Nambiar P, Minaguchi K, Umetsu K, et al.
    PLoS One, 2016;11(6):e0158463.
    PMID: 27355212 DOI: 10.1371/journal.pone.0158463
    Mitochondrial DNA (mtDNA) serves as a powerful tool for exploring matrilineal phylogeographic ancestry, as well as for analyzing highly degraded samples, because of its polymorphic nature and high copy numbers per cell. The recent advent of complete mitochondrial genome sequencing has led to improved techniques for phylogenetic analyses based on mtDNA, and many multiplex genotyping methods have been developed for the hierarchical analysis of phylogenetically important mutations. However, few high-resolution multiplex genotyping systems for analyzing East-Asian mtDNA can be applied to extremely degraded samples. Here, we present a multiplex system for analyzing mitochondrial single nucleotide polymorphisms (mtSNPs), which relies on a novel amplified product-length polymorphisms (APLP) method that uses inosine-flapped primers and is specifically designed for the detailed haplogrouping of extremely degraded East-Asian mtDNAs. We used fourteen 6-plex polymerase chain reactions (PCRs) and subsequent electrophoresis to examine 81 haplogroup-defining SNPs and 3 insertion/deletion sites, and we were able to securely assign the studied mtDNAs to relevant haplogroups. Our system requires only 1×10-13 g (100 fg) of crude DNA to obtain a full profile. Owing to its small amplicon size (<110 bp), this new APLP system was successfully applied to extremely degraded samples for which direct sequencing of hypervariable segments using mini-primer sets was unsuccessful, and proved to be more robust than conventional APLP analysis. Thus, our new APLP system is effective for retrieving reliable data from extremely degraded East-Asian mtDNAs.
    Matched MeSH terms: Sequence Analysis, DNA/methods*
  2. From the High Arctic to the Equator: Do Soil Metagenomes Differ According to Our Expectations?
    Kerfahi D, Tripathi BM, Dong K, Kim M, Kim H, Ferry Slik JW, et al.
    Microb Ecol, 2019 Jan;77(1):168-185.
    PMID: 29882154 DOI: 10.1007/s00248-018-1215-z
    Comparing the functional gene composition of soils at opposite extremes of environmental gradients may allow testing of hypotheses about community and ecosystem function. Here, we were interested in comparing how tropical microbial ecosystems differ from those of polar climates. We sampled several sites in the equatorial rainforest of Malaysia and Brunei, and the high Arctic of Svalbard, Canada, and Greenland, comparing the composition and the functional attributes of soil biota between the two extremes of latitude, using shotgun metagenomic Illumina HiSeq2000 sequencing. Based upon "classical" views of how tropical and higher latitude ecosystems differ, we made a series of predictions as to how various gene function categories would differ in relative abundance between tropical and polar environments. Results showed that in some respects our predictions were correct: the polar samples had higher relative abundance of dormancy related genes, and lower relative abundance of genes associated with respiration, and with metabolism of aromatic compounds. The network complexity of the Arctic was also lower than the tropics. However, in various other respects, the pattern was not as predicted; there were no differences in relative abundance of stress response genes or in genes associated with secondary metabolism. Conversely, CRISPR genes, phage-related genes, and virulence disease and defense genes, were unexpectedly more abundant in the Arctic, suggesting more intense biotic interaction. Also, eukaryote diversity and bacterial diversity were higher in the Arctic of Svalbard compared to tropical Brunei, which is consistent with what may expected from amplicon studies in terms of the higher pH of the Svalbard soil. Our results in some respects confirm expectations of how tropical versus polar nature may differ, and in other respects challenge them.
    Matched MeSH terms: Sequence Analysis, DNA
  3. Tropical soil bacterial communities in Malaysia: pH dominates in the equatorial tropics too
    Tripathi BM, Kim M, Singh D, Lee-Cruz L, Lai-Hoe A, Ainuddin AN, et al.
    Microb Ecol, 2012 Aug;64(2):474-84.
    PMID: 22395784 DOI: 10.1007/s00248-012-0028-8
    The dominant factors controlling soil bacterial community variation within the tropics are poorly known. We sampled soils across a range of land use types--primary (unlogged) and logged forests and crop and pasture lands in Malaysia. PCR-amplified soil DNA for the bacterial 16S rRNA gene targeting the V1-V3 region was pyrosequenced using the 454 Roche machine. We found that land use in itself has a weak but significant effect on the bacterial community composition. However, bacterial community composition and diversity was strongly correlated with soil properties, especially soil pH, total carbon, and C/N ratio. Soil pH was the best predictor of bacterial community composition and diversity across the various land use types, with the highest diversity close to neutral pH values. In addition, variation in phylogenetic structure of dominant lineages (Alphaproteobacteria, Beta/Gammaproteobacteria, Acidobacteria, and Actinobacteria) is also significantly correlated with soil pH. Together, these results confirm the importance of soil pH in structuring soil bacterial communities in Southeast Asia. Our results also suggest that unlike the general diversity pattern found for larger organisms, primary tropical forest is no richer in operational taxonomic units of soil bacteria than logged forest, and agricultural land (crop and pasture) is actually richer than primary forest, partly due to selection of more fertile soils that have higher pH for agriculture and the effects of soil liming raising pH.
    Matched MeSH terms: Sequence Analysis, DNA/methods
  4. Distinctive bacterial communities in the rhizoplane of four tropical tree species
    Oh YM, Kim M, Lee-Cruz L, Lai-Hoe A, Go R, Ainuddin N, et al.
    Microb Ecol, 2012 Nov;64(4):1018-27.
    PMID: 22767122 DOI: 10.1007/s00248-012-0082-2
    It is known that the microbial community of the rhizosphere is not only influenced by factors such as root exudates, phenology, and nutrient uptake but also by the plant species. However, studies of bacterial communities associated with tropical rainforest tree root surfaces, or rhizoplane, are lacking. Here, we analyzed the bacterial community of root surfaces of four species of native trees, Agathis borneensis, Dipterocarpus kerrii, Dyera costulata, and Gnetum gnemon, and nearby bulk soils, in a rainforest arboretum in Malaysia, using 454 pyrosequencing of the 16S rRNA gene. The rhizoplane bacterial communities for each of the four tree species sampled clustered separately from one another on an ordination, suggesting that these assemblages are linked to chemical and biological characteristics of the host or possibly to the mycorrhizal fungi present. Bacterial communities of the rhizoplane had various similarities to surrounding bulk soils. Acidobacteria, Alphaproteobacteria, and Betaproteobacteria were dominant in rhizoplane communities and in bulk soils from the same depth (0-10 cm). In contrast, the relative abundance of certain bacterial lineages on the rhizoplane was different from that in bulk soils: Bacteroidetes and Betaproteobacteria, which are known as copiotrophs, were much more abundant in the rhizoplane in comparison to bulk soil. At the genus level, Burkholderia, Acidobacterium, Dyella, and Edaphobacter were more abundant in the rhizoplane. Burkholderia, which are known as both pathogens and mutualists of plants, were especially abundant on the rhizoplane of all tree species sampled. The Burkholderia species present included known mutualists of tropical crops and also known N fixers. The host-specific character of tropical tree rhizoplane bacterial communities may have implications for understanding nutrient cycling, recruitment, and structuring of tree species diversity in tropical forests. Such understanding may prove to be useful in both tropical forestry and conservation.
    Matched MeSH terms: Sequence Analysis, DNA/methods
  5. Rainforest Conversion to Rubber Plantation May Not Result in Lower Soil Diversity of Bacteria, Fungi, and Nematodes
    Kerfahi D, Tripathi BM, Dong K, Go R, Adams JM
    Microb Ecol, 2016 08;72(2):359-71.
    PMID: 27221090 DOI: 10.1007/s00248-016-0790-0
    Large areas of rainforest in Asia have been converted to plantations, with uncertain effects on soil biodiversity. Using standard metagenetic methods, we compared the soil biota of bacteria, fungi, and nematodes at three rainforest sites in Malaysia with two rubber plantation sites with similar soils and geology. We predicted the following: (1) that the rubber sites would have a lower α- and β-diversity than the rainforest sites, due to the monospecific canopy cover and intensive management with herbicides, pesticides, and fertilizers, and (2) that due to differences in the physical and biotic environment associated with cultivation, there would be distinct communities of bacteria, fungi, and nematodes. However, regarding (1), the results showed no consistent difference in α- and β-diversity of bacteria, fungi, or nematodes between rainforest and rubber plantation sites. It appears that conversion of rainforest to rubber plantations does not necessarily result in a decrease in diversity of soil biota. It may be that heterogeneity associated with the cultivation regimen compensates for loss of biotically imposed heterogeneity of the original rainforest. Regarding (2), as predicted there were statistically significant differences in community composition between rainforest and rubber plantation for bacteria, fungi, and nematodes. These differences could be related to a range of factors including light level, litter fall composition, pH, C and N, selecting a distinct set of soil taxa, and it is possible that this in itself would affect long-term soil function.
    Matched MeSH terms: Sequence Analysis, DNA
  6. Fulltext Impact of logging and forest conversion to oil palm plantations on soil bacterial communities in Borneo
    Lee-Cruz L, Edwards DP, Tripathi BM, Adams JM
    Appl Environ Microbiol, 2013 Dec;79(23):7290-7.
    PMID: 24056463 DOI: 10.1128/AEM.02541-13
    Tropical forests are being rapidly altered by logging and cleared for agriculture. Understanding the effects of these land use changes on soil bacteria, which constitute a large proportion of total biodiversity and perform important ecosystem functions, is a major conservation frontier. Here we studied the effects of logging history and forest conversion to oil palm plantations in Sabah, Borneo, on the soil bacterial community. We used paired-end Illumina sequencing of the 16S rRNA gene, V3 region, to compare the bacterial communities in primary, once-logged, and twice-logged forest and land converted to oil palm plantations. Bacteria were grouped into operational taxonomic units (OTUs) at the 97% similarity level, and OTU richness and local-scale α-diversity showed no difference between the various forest types and oil palm plantations. Focusing on the turnover of bacteria across space, true β-diversity was higher in oil palm plantation soil than in forest soil, whereas community dissimilarity-based metrics of β-diversity were only marginally different between habitats, suggesting that at large scales, oil palm plantation soil could have higher overall γ-diversity than forest soil, driven by a slightly more heterogeneous community across space. Clearance of primary and logged forest for oil palm plantations did, however, significantly impact the composition of soil bacterial communities, reflecting in part the loss of some forest bacteria, whereas primary and logged forests did not differ in composition. Overall, our results suggest that the soil bacteria of tropical forest are to some extent resilient or resistant to logging but that the impacts of forest conversion to oil palm plantations are more severe.
    Matched MeSH terms: Sequence Analysis, DNA
  7. Fulltext Worldwide increased prevalence of human adenovirus type 3 (HAdV-3) respiratory infections is well correlated with heterogeneous hypervariable regions (HVRs) of hexon
    Haque E, Banik U, Monwar T, Anthony L, Adhikary AK
    PLoS One, 2018;13(3):e0194516.
    PMID: 29590206 DOI: 10.1371/journal.pone.0194516
    Human adenovirus type 3 (HAdV-3) respiratory infections occurs worldwide in both children and adults, leading to severe morbidity and mortality, particularly in the paediatric age group and especially in neonates. During HAdV infection, neutralizing antibodies are formed against the epitopes located in the hyper variable regions (HVRs) of the hexon protein. These neutralizing antibodies provide protection against reinfection by viruses of the same type. Therefore it is reasonable to speculate that variations of HAdV-3 in the HVRs could impair the immunity acquired by previous infection with a different strain with variation in its HVRs. HAdV-3 has recently become the major agent of acute respiratory infection worldwide, being responsible for 15% to 87% of all adenoviral respiratory infections. However, despite the increased prevalence of HAdV-3 as respiratory pathogen, the diversity of hexon proteins in circulating strains remains unexplored. This study was designed to explore the variation in HVRs of hexon among globally distributed strains of HAdV-3 as well as to discover possible relationship among them, thus possibly shedding light on the cause for the increased prevalence of HAdV-3. In this study, for the first time we analysed the hexon proteins of all 248 available strains of HAdV-3 from the NCBI database and compared them with those of the HAdV-3 prototype (GB stain). We found that the HVRs of HAdV-3 strains circulating worldwide were highly heterogeneous and have been mutating continuously since -their original isolation. Based on their immense heterogeneity, the strains can be categorized into 25 hexon variants (3Hv-1 to 3Hv-25), 4 of which (3Hv-1 to 3Hv-4) comprises 80% of the strains. This heterogeneity may explain why HAdV-3 has become the most prevalent HAdVs type worldwide. The heterogeneity of hexon proteins also shows that the development of a vaccine against HAdV-3 might be challenging. The data on hexon variants provided here may be useful for the future epidemiological study of HAdV-3 infection.
    Matched MeSH terms: Sequence Analysis, DNA
  8. Haemoglobin Constant Spring (HbA2: c.427T>C) and Haemoglobin Adana (HbA2: c.179G>A) in jaundiced Malaysian term neonates with clinically significant hyperbilirubinemia
    Shwe S, Boo NY, Ong HK, Chee SC, Maslina M, Ling MMM, et al.
    Malays J Pathol, 2020 Aug;42(2):253-257.
    PMID: 32860378
    INTRODUCTION: Haemoglobin Constant Spring (Hb CoSp) and Haemoglobin Adana (Hb Adana), are two non-deletion type of α-thalassemia reported in Malaysia. Owing to their structural instability, they cause hemolysis and hyperbilirubinemia. This observational study was part of a large study investigating multiple factors associated with severe neonatal jaundice. In this part we aimed to determine the prevalence of Hb CoSp and Hb Adana and their association with clinically significant neonatal hyperbilirubinemia (SigNH, total serum bilirubin (TSB>290µmol/L)) among jaundiced Malaysian term neonates.

    MATERIALS AND METHODS: The inclusion criteria were normal term-gestation neonates admitted consecutively for phototherapy. PCR-restriction fragment length polymorphism method was applied on DNA extracted from dry blood spot specimens of each neonate to detect for Hb CoSp and Hb Adana gene. Positive samples were verified by gene sequencing.

    RESULTS: Of the 1121 neonates recruited (719 SigNH and 402 no-SigNH), heterozygous Hb CoSp gene was detected in only two (0.27%) neonates. Both were SigNH neonates (0.3% or 2/719). No neonate had Hb Adana variant.

    CONCLUSION: Hb CoSp was not common but could be a risk factor associated with SigNH. No Hb Adana was detected.

    Matched MeSH terms: Sequence Analysis, DNA
  9. Fulltext Pathogenicity of a microsporidium isolate from the diamondback moth against Noctuid moths: characterization and implications for microbiological pest management
    Ghani IA, Dieng H, Abu Hassan ZA, Ramli N, Kermani N, Satho T, et al.
    PLoS One, 2013;8(12):e81642.
    PMID: 24349104 DOI: 10.1371/journal.pone.0081642
    Due to problems with chemical control, there is increasing interest in the use of microsporidia for control of lepidopteran pests. However, there have been few studies to evaluate the susceptibility of exotic species to microsporidia from indigenous Lepidoptera.
    Matched MeSH terms: Sequence Analysis, DNA
  10. Fulltext First Two Cases of Fungal Infections Associated with Multi-drug Resistant Yeast, Fereydounia khargensis
    Tap RM, Ramli NY, Sabaratnam P, Hashim R, Bakri AR, Bee LB, et al.
    Mycopathologia, 2016 Aug;181(7-8):531-7.
    PMID: 27010640 DOI: 10.1007/s11046-016-0002-y
    The number of new fungal pathogens is increasing due to growing population of immunocompromised patients and advanced identification techniques. Fereydounia khargensis is a yeast and was first described in 2014 from environmental samples. As far as we know, this is the first report of human infections associated with F. khargensis. The yeasts were isolated from blood of a HIV-positive patient and pleural fluid of chronic renal failure patient. Amplification and sequencing of the internal transcribed spacer and the large subunit regions confirmed the identity of the isolates. Both isolates showed multi-drug resistance to antifungal agents tested.
    Matched MeSH terms: Sequence Analysis, DNA
  11. Chaetomium globosum Cutaneous Fungal Infection Confirmed by Molecular Identification: A Case Report from Malaysia
    Mohd Tap R, Sabaratnam P, Ahmad NA, Abd Razak MF, Hashim R, Ahmad N
    Mycopathologia, 2015 Aug;180(1-2):137-41.
    PMID: 25894509 DOI: 10.1007/s11046-015-9890-5
    An 11-year-old girl presented with multiple blisters on her the right foot complicated with cellulitis. The conventional and molecular identification were performed on the culture. The internal transcribed spacer (ITS) region in rRNA gene of the isolate was amplified by PCR. The sequence of the amplified ITS region matched 99 % with that of Chaetomium globosum in the GenBank. This is the first report describing C. globosum causing cutaneous infection in Malaysia.
    Matched MeSH terms: Sequence Analysis, DNA
  12. Fulltext Molecular insights of co-trimoxazole resistance genes in Haemophilus influenzae isolated in Malaysia
    Mohd-Zain Z, Kamsani NH, Ahmad N
    Trop Biomed, 2013 Dec;30(4):584-90.
    PMID: 24522126 MyJurnal
    In the last few decades, co-trimoxazole (SXT), an antibacterial combination of trimethoprim and sulfamethoxazole, has been used for treatment of upper respiratory tract infection due to Haemophilus influenzae. The usage of this antibiotic has become less important due to emergence of SXT-resistant strains worldwide. Most reports associate SXT resistance to the presence of variants of dihydrofolate reductase (DHFR) dfrA genes which are responsible for trimethoprim resistance; while the sulfamethoxazole (SMX) resistance are due to sulfonamide (SUL) genes sul1 and sul2 and/or mutation in the chromosomal (folP) gene encoding dihydropteroate synthetase (DHPS). This study aims to detect and analyse the genes that are involved in SXT resistance in H. influenzae strains that were isolated in Malaysia. Primers targeting for variants of dfrA, fol and sul genes were used to amplify the genes in nine SXT-resistant strains. The products of amplification were sequenced and multiple alignments of the assembled sequences of the local strains were compared to the sequences of other H. influenzae strains in the Genbank. Of the five variants of the dhfA genes, dfrA1 was detected in three out of the nine strains. In contrast to intermediate strains, at least one variant of folP genes was detected in the resistant strains. Multiple nucleotide alignment of this gene revealed that strain H152 was genetically different from the others due to a 15-bp nucleotide insert in folP gene. The sequence of the insert was similar to the insert in folP of H. influenzae strain A12, a strain isolated in United Kingdom. None of the strains had sul1 gene but sul2 gene was detected in four strains. Preliminary study on the limited number of samples shows that the TMP resistance was attributed to mainly to dfrA1 and the SMX was due to folP genes. Presence of sul2 in addition to folP in seven strains apparently had increased their level of resistance. A strain that lacked sul1 or sul2 gene, its resistance to sulfonamide was attributed to a 15-bp DNA insert in the folP gene.
    Matched MeSH terms: Sequence Analysis, DNA
  13. Fulltext Sequencing crop genomes: a gateway to improve tropical agriculture
    Thottathil, Gincy Paily, Jayasekaran, Kandakumar, Ahmad Sofiman Othman
    Trop Life Sci Res, 2016;27(1):93-114.
    MyJurnal
    Agricultural development in the tropics lags behind development in the
    temperate latitudes due to the lack of advanced technology, and various biotic and abiotic
    factors. To cope with the increasing demand for food and other plant-based products,
    improved crop varieties have to be developed. To breed improved varieties, a better
    understanding of crop genetics is necessary. With the advent of next-generation DNA
    sequencing technologies, many important crop genomes have been sequenced. Primary
    importance has been given to food crops, including cereals, tuber crops, vegetables, and
    fruits. The DNA sequence information is extremely valuable for identifying key genes
    controlling important agronomic traits and for identifying genetic variability among the
    cultivars. However, massive DNA re-sequencing and gene expression studies have to be
    performed to substantially improve our understanding of crop genetics. Application of the
    knowledge obtained from the genomes, transcriptomes, expression studies, and
    epigenetic studies would enable the development of improved varieties and may lead to a
    second green revolution. The applications of next generation DNA sequencing
    technologies in crop improvement, its limitations, future prospects, and the features of
    important crop genome projects are reviewed herein.
    Matched MeSH terms: Sequence Analysis, DNA
  14. Chryseobacterium artocarpi sp. nov., isolated from the rhizosphere soil of Artocarpus integer
    Venil CK, Nordin N, Zakaria ZA, Ahmad WA
    Int J Syst Evol Microbiol, 2014 Sep;64(Pt 9):3153-9.
    PMID: 24958763 DOI: 10.1099/ijs.0.063594-0
    A bacterial strain, designated UTM-3(T), isolated from the rhizosphere soil of Artocarpus integer (cempedak) in Malaysia was studied to determine its taxonomic position. Cells were Gram-stain-negative, non-spore-forming rods, devoid of flagella and gliding motility, that formed yellow-pigmented colonies on nutrient agar and contained MK-6 as the predominant menaquinone. Comparative analysis of the 16S rRNA gene sequence of strain UTM-3(T) with those of the most closely related species showed that the strain constituted a distinct phyletic line within the genus Chryseobacterium with the highest sequence similarities to Chryseobacterium lactis NCTC 11390(T), Chryseobacterium viscerum 687B-08(T), Chryseobacterium tructae 1084-08(T), Chryseobacterium arthrosphaerae CC-VM-7(T), Chryseobacterium oncorhynchi 701B-08(T), Chryseobacterium vietnamense GIMN1.005(T), Chryseobacterium bernardetii NCTC 13530(T), Chryseobacterium nakagawai NCTC 13529(T), Chryseobacterium gallinarum LMG 27808(T), Chryseobacterium culicis R4-1A(T), Chryseobacterium flavum CW-E2(T), Chryseobacterium aquifrigidense CW9(T), Chryseobacterium ureilyticum CCUG 52546(T), Chryseobacterium indologenes NBRC 14944(T), Chryseobacterium gleum CCUG 14555(T), Chryseobacterium jejuense JS17-8(T), Chryseobacterium oranimense H8(T) and Chryseobacterium joostei LMG 18212(T). The major whole-cell fatty acids were iso-C15 : 0 and iso-C17 : 1ω9c, followed by summed feature 4 (iso-C15 : 0 2-OH and/or C16 : 1ω7t) and iso-C17 : 0 3-OH, and the polar lipid profile consisted of phosphatidylethanolamine and several unknown lipids. The DNA G+C content strain UTM-3(T) was 34.8 mol%. On the basis of the phenotypic and phylogenetic evidence, it is concluded that the isolate represents a novel species of the genus Chryseobacterium, for which the name Chryseobacterium artocarpi sp. nov. is proposed. The type strain is UTM-3(T) ( = CECT 8497(T) = KCTC 32509(T)).
    Matched MeSH terms: Sequence Analysis, DNA
  15. Fulltext Terrestrial Animal-Derived Rabies Virus in a Juvenile Indian Flying Fox in Sri Lanka
    Matsumoto T, Nanayakkara S, Perera D, Ushijima S, Wimalaratne O, Nishizono A, et al.
    Jpn J Infect Dis, 2017 Nov 22;70(6):693-695.
    PMID: 29093322 DOI: 10.7883/yoken.JJID.2017.249
    Matched MeSH terms: Sequence Analysis, DNA
  16. Fulltext Genetic fine structure of a Salmonella enterica serovar Typhi strain associated with the 2005 outbreak of typhoid fever in Kelantan, Malaysia
    Baddam R, Kumar N, Thong KL, Ngoi ST, Teh CS, Yap KP, et al.
    J Bacteriol, 2012 Jul;194(13):3565-6.
    PMID: 22689247 DOI: 10.1128/JB.00581-12
    Among enteric pathogens, Salmonella enterica serovar Typhi is responsible for the largest number of food-borne outbreaks and fatalities. The ability of the pathogen to cause systemic infection for extended durations leads to a high cost of disease control. Chronic carriers play important roles in the evolution of Salmonella Typhi; therefore, identification and in-depth characterization of isolates from clinical cases and carriers, especially those from zones of endemicity where the pathogen has not been extensively studied, are necessary. Here, we describe the genome sequence of the highly virulent Salmonella Typhi strain BL196/05 isolated during the outbreak of typhoid in Kelantan, Malaysia, in 2005. The whole-genome sequence and comparative genomics of this strain should enable us to understand the virulence mechanisms and evolutionary dynamics of this pathogen in Malaysia and elsewhere.
    Matched MeSH terms: Sequence Analysis, DNA
  17. The mitochondrial 16 s rRNA reveals high anthropogenic influence on land snail diversity in a preliminary island survey
    Abu-Bakar SB, Razali NM, Naggs F, Wade C, Mohd-Nor SA, Aileen-Tan SH
    Mol Biol Rep, 2014 Mar;41(3):1799-805.
    PMID: 24443224 DOI: 10.1007/s11033-014-3029-5
    A total of 30 specimens belonging to five species, namely; Cryptozona siamensis, Sarika resplendens and Sarika sp. from the family Ariophantidae as well as Quantula striata and Quantula sp. from the family Dyakiidae were collected from the Langkawi Island in Northern Peninsular Malaysia. All specimens were identified through comparisons of shell morphology and amplification of a 500 bp segment of the 16S rRNA mtDNA gene. To assess phylogenetic insights, the sequences were aligned using ClustalW and phylogenetic trees were constructed. The analyses showed two major lineages in both Maximum Parsimony and Neighbour Joining phylogenetic trees. Each putative taxonomic group formed a monophyletic cluster. Our study revealed low species and intraspecies genetic diversities based on the 16S rRNA gene sequences. Thus, this study has provided an insight of land snail diversity in populations of an island highly influenced by anthropogenic activities through complementary use of shell morphological and molecular data.
    Matched MeSH terms: Sequence Analysis, DNA
  18. Genetic diversity of chicken anemia virus following cell culture passaging in MSB-1 cells
    Hasmah MS, Omar AR, Wan KF, Hair-Bejo M, Aini I
    Acta Virol., 2004;48(2):85-9.
    PMID: 15462283
    It has been shown that a chicken anemia virus (CAV) isolates which had undergone 60 passages in MSB-1 cells (SMSC-1/P60, 3-1/P60) acquired 33-66 nucleotide substitutions at the coding region resulting in 13-16 amino acid changes as compared to the CAV isolates passaged only 5 times in MSB-1 cells (SMSC-1 and 3-1) (Chowdhury et al., Arch. Virol. 148, 2437-2448, 2003). In this study we found that a low CAV (BL-5) and a high CAV passage (BL-5/P90) differed by only 15 nucleotide substitutions resulting in 11 amino acid changes. Phylogenetic analysis based on VP1 also revealed that both isolates were close to each other but not to other CAV isolates from Malaysia, namely SMSC-1 and 3-1.
    Matched MeSH terms: Sequence Analysis, DNA
  19. Sequence and phylogenetic analysis of the VP2 gene of very virulent infectious bursal disease virus isolates
    Hoque MM, Omar AR, Hair-Bejo M, Aini I
    J. Biochem. Mol. Biol. Biophys., 2002 Apr;6(2):93-9.
    PMID: 12186763
    Previously we have shown that very virulent infectious bursal disease viruses (vvIBDV) that are SspI, TaqI and StyI positive (92/04, 97/61 and 94/B551) but not SspI and TaqI positive and StyI negative (94/273) cause high mortality, up to 80% in specific-pathogen-free chickens with significant damage of the bursal as well as nonbursal tissues. In this study, we sequenced the VP2 gene (1351 bp) of the 92/04, 94/273 and 94/B551 and compared them with other IBDV strains. All the isolates have the unique amino acid residues at positions 222A, 256I, 294I and 299S found in other vvIBDV strains. The deduced VP2 amino acids encoded by 92/04 is identical to the vvIBDV strains from Israel (IBDVKS), Japan (OKYM) and Europe (UK661), whereas the 94/273 and 94/B551 isolates have one to three amino acid substitutions. The 94/273 has two amino acid substitutions at positions 254 G to S and at 270 A to E that have not been reported before from vvIBDV strains. The 94/B551 also has one amino acid substitution at position 300 E to S, which is uncommon among other vvIBDV strains. However, phylogenetic analysis suggested that the isolates are very close to each other and all of them may have derived from the same origin as vvIBDV strains isolated from China, Japan and Europe. Even though antigenic index analysis of the 94/273 and 94/B551 indicated that the isolates are unique compared to other IBDV strains, their antigenic variation remain to be determined by monoclonal antibody study.
    Matched MeSH terms: Sequence Analysis, DNA
  20. Pathogenicity and molecular analysis of an infectious bursal disease virus isolated from Malaysian village chickens
    Tan DY, Hair-Bejo M, Omar AR, Aini I
    Avian Dis, 2004 Apr-Jun;48(2):410-6.
    PMID: 15283430
    The characteristics of the pathogenic infectious bursal disease virus (IBDV) that infected avian species other than commercial chickens were largely unknown. In this study, by using in vivo and molecular methods, we had characterized an IBDV isolate (named 94268) isolated from an infectious bursal disease (IBD) outbreak in Malaysian village chickens--the adulterated descendant of the Southeast Asian jungle fowl (Gallus bankiva) that were commonly reared in the backyard. The 94268 isolate was grouped as the very virulent IBDV (vvIBDV) strain because it caused severe lesions and a high mortality rate in village chickens (>88%) and experimentally infected specific-pathogen-free chickens (>66%). In addition, it possessed all of the vvIBDV molecular markers in its VP2 gene. Phylogenetic analysis using distance, maximum parsimony, and maximum likelihood methods revealed that 94268 was monophyletic with other vvIBDV isolates and closely related to the Malaysian vvIBDV isolates. Given that the VP2 gene of 94268 isolate was almost identical and evolutionarily closely related to other field IBDV isolates that affected the commercial chickens, we therefore concluded that IBD infections had spread across the farm boundary. IBD infection in the village chicken may represent an important part of the IBD epidemiology because these birds could harbor the vvIBDV strain and should not be overlooked in the control and prevention of the disease.
    Matched MeSH terms: Sequence Analysis, DNA/veterinary
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