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Lee L.-H.,Sunway University | Zainal N.,Sunway University | Zainal N.,University of Malaya | Azman A.-S.,Sunway University | And 3 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2014

A novel actinobacterial strain, designated MUSC 201T, was isolated from a mangrove soil collected from Kuantan, the capital city of Pahang State in Malaysia. The taxonomic status of this strain was determined using a polyphasic approach. Comparative 16S rRNA gene sequence analysis revealed that strain MUSC 201T represented a novel lineage within the class Actinobacteria. Strain MUSC 201T formed a distinct clade in the family Nocardioidaceae and was most closely related to the members of the genera Nocardioides (16S rRNA gene sequence similarity, 91.9-95.1 %), Aeromicrobium (92.7-94.6 %), Marmoricola (92.5-93.1 %) and Kribbella (91.5-92.4 %). The cells of this strain were irregular coccoid to short rod shaped. The peptidoglycan contained LL-diaminopimelic acid as diagnostic diamino acid and the peptidoglycan type was A3c. The peptidoglycan cell wall contained LL-diaminopimelic acid, glycine, glutamic acid and alanine in a molar ratio of 1.5: 0.9: 1.0: 1.5. The cell-wall sugars were galactose and rhamnose. The predominant menaquinone was MK-9(H4). The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphoglycolipid, glycolipid and four unknown phospholipids. The major cellular fatty acids were C18: 1ω9c (30.8 %), C16: 0 (24.1 %), and 10- methyl C18: 0 (13.9 %). The DNA G+C content was 72.0±0.1 mol%. On the basis of phylogenetic and phenotypic differences from members of the genera of the family Nocardioidaceae, a novel genus and species, Mumia flava gen. nov., sp. nov. are proposed. The type strain of Mumia flava is MUSC 201T (=DSM 27763T=MCCC 1A00646T=NBRC 109973T). © 2014 IUMS.


Khoo T.S.,UKM Medical Molecular Biology Institute UMBI | Hamidah Hussin N.,Medical Center | Then S.-M.,UKM Medical Molecular Biology Institute UMBI | Jamal R.,UKM Medical Molecular Biology Institute UMBI
Differentiation | Year: 2013

Human embryonic stem cells (hESc) are known for its pluripotency and self renewal capability, thus possess great potential in regenerative medicine. However, the lack of suitable xenofree extracellular matrix substrate inhibits further applications or the use of hESc in cell-based therapy. In this study, we described a new differentiation method, which generates a homogeneous population of mesenchymal progenitor cells (hESc-MPC) from hESc via epithelial-mesenchymal transition. The extracellular matrix (ECM) proteins from hESc-MPC had in turn supported the undifferentiated expansion of hESc. Immunocytochemistry and flow cytometry characterization of hESc-MPC revealed the presence of early mesenchymal markers. Tandem mass spectometry analysis of ECM produced by hESc-MPC revealed the presence of a mixture of extracellular proteins which includes tenascin C, fibronectin, and vitronectin. The pluripotency of hESc (MEL-1) cultured on the ECM was maintained as shown by the expression of pluripotent genes (FoxD3, Oct-4, Tdgf1, Sox-2, Nanog, hTERT, Rex1), protein markers (SSEA-3, SSEA-4, TRA-1-81, TRA-1-60, Oct-4.) and the ability to differentiate into cells representative of ectoderm, endoderm and mesoderm. In summary, we have established a xeno-free autogenic feeder free system to support undifferentiated expansion of hESc, which could be of clinical relevance. © 2013 International Society of Differentiation.


Ker-Woon C.,National University of Malaysia | Ghafar N.A.,National University of Malaysia | Ghafar N.A.,UKM Medical Molecular Biology Institute UMBI | Kien Hui C.,National University of Malaysia | And 3 more authors.
BMC Cell Biology | Year: 2015

Background: Acacia honey (AH) has been proven to improve skin wound healing, but its therapeutic effects on corneal epithelium has not been elucidated to date. This study aimed to investigate the effects of AH on cultured corneal epithelial cells (CEC) on in vitro corneal abrasion wound healing model. Six New Zealand white rabbits' CEC were isolated and cultured until passage 1. Circular wound area was created onto a confluent monolayer CEC using a corneal trephine which mimicked corneal abrasion and treated with 0.025% AH supplemented in basal medium (BM) and complete cornea medium (CCM). Wound healing was measured as the percentage of wound closure by the migration of CEC on day 0, day 3 and day 6, post wound creation. The morphological changes of CEC were assessed via phase contrast microscopy. Gene and protein expressions of cytokeratin (CK3), fibronectin and cluster of differentiation 44 (CD44) in AH treated groups and control groups were determined by real-time PCR and immunocytochemistry, respectively. Results: Cultured CEC exhibited similar morphology of polygonal shaped cells in all culture media. CEC cultured in AH-supplemented media showed higher percentage of wound closure compared to the controls. Gene expression of CK3 increased in AH-supplemented groups throughout the study. Fibronectin expression was increased at the initial stage while CD44 expression was increased at day 3, post wound creation. The protein expression of CEC cultured in all media was in accordance to their respective gene expressions. Conclusion: Supplementation of AH in BM and CCM media accelerates CEC wound closure of the in vitro corneal abrasion model by increasing the expression of genes and proteins associated with CEC wound healing. © Ker-Woon et al.; licensee.


PubMed | National University of Malaysia and UKM Medical Molecular Biology Institute UMBI
Type: | Journal: BMC cell biology | Year: 2015

Acacia honey (AH) has been proven to improve skin wound healing, but its therapeutic effects on corneal epithelium has not been elucidated to date. This study aimed to investigate the effects of AH on cultured corneal epithelial cells (CEC) on in vitro corneal abrasion wound healing model. Six New Zealand white rabbits CEC were isolated and cultured until passage 1. Circular wound area was created onto a confluent monolayer CEC using a corneal trephine which mimicked corneal abrasion and treated with 0.025% AH supplemented in basal medium (BM) and complete cornea medium (CCM). Wound healing was measured as the percentage of wound closure by the migration of CEC on day 0, day 3 and day 6, post wound creation. The morphological changes of CEC were assessed via phase contrast microscopy. Gene and protein expressions of cytokeratin (CK3), fibronectin and cluster of differentiation 44 (CD44) in AH treated groups and control groups were determined by real-time PCR and immunocytochemistry, respectively.Cultured CEC exhibited similar morphology of polygonal shaped cells in all culture media. CEC cultured in AH-supplemented media showed higher percentage of wound closure compared to the controls. Gene expression of CK3 increased in AH-supplemented groups throughout the study. Fibronectin expression was increased at the initial stage while CD44 expression was increased at day 3, post wound creation. The protein expression of CEC cultured in all media was in accordance to their respective gene expressions.Supplementation of AH in BM and CCM media accelerates CEC wound closure of the in vitro corneal abrasion model by increasing the expression of genes and proteins associated with CEC wound healing.


Lim M.N.,Institute for Medical Research | Lim M.N.,National University of Malaysia | Hussin N.H.,National University of Malaysia | Othman A.,National University of Malaysia | And 4 more authors.
Molecular Vision | Year: 2012

Purpose: The presence of multipotent human limbal stromal cells resembling mesenchymal stromal cells (MSC) provides new insights to the characteristic of these cells and its therapeutic potential. However, little is known about the expression of stage-specific embryonic antigen 4 (SSEA-4) and the embryonic stem cell (ESC)-like properties of these cells. We studied the expression of SSEA-4 surface protein and the various ESC and MSC markers in the ex vivo cultured limbal stromal cells. The phenotypes and multipotent differentiation potential of these cells were also evaluated. Methods: Limbal stromal cells were derived from corneoscleral rims. The SSEA-4+ and SSEA-4- limbal stromal cells were sorted by fluorescence-activated cells sorting (FACS). Isolated cells were expanded and reanalyzed for their expression of SSEA-4. Expression of MSC and ESC markers on these cells were also analyzed by FACS. In addition, expression of limbal epithelial and corneal stromal proteins such as ATP-binding cassette sub-family G member 2 (ABCG2), tumour protein p63 (p63), paired box 6 (Pax6), cytokeratin 3 (AE5), cytokeratin 10, and keratocan sulfate were evaluated either by immunofluorecence staining or reverse transcription polymerase chain reaction. Appropriate induction medium was used to differentiate these cells into adipocytes, osteocytes, and chondrocytes. Results: Expanded limbal stromal cells expressed the majority of mesenchymal markers. These cells were negative for ABCG2, p63, Pax6, AE-5, and keratocan sulfate. After passaged, a subpopulation of these cells showed low expression of SSEA-4 but were negative for other important ESC surface markers such as Tra-1-60, Tra-1-81, and transcription factors like octamer-binding transcription factor 4 (Oct4), SRY(sex determining region Y)-box 2 (Sox2), and Nanog. Early passaged cells when induced were able to differentiate into adipocytes, osteocytes and chondrocytes. Conclusions: The expanded limbal stromal cells showed features of multipotent MSC. Our study confirmed the expression of SSEA-4 by a subpopulation of cultured limbal stromal cells. However, despite the expression of SSEA-4, these cells did not express any other markers of ESC. Therefore, we conclude that the cells did not show properties of ESC. © 2012 Molecular Vision.


Law J.W.,University of Selangor | Ab Mutalib N.-S.,UKM Medical Molecular Biology Institute UMBI | Chan K.-G.,University of Malaya | Lee L.-H.,University of Selangor
Frontiers in Microbiology | Year: 2015

The incidence of foodborne diseases has increased over the years and resulted in major public health problem globally. Foodborne pathogens can be found in various foods and it is important to detect foodborne pathogens to provide safe food supply and to prevent foodborne diseases. The conventional methods used to detect foodborne pathogen are time consuming and laborious. Hence, a variety of methods have been developed for rapid detection of foodborne pathogens as it is required in many food analyses. Rapid detection methods can be categorized into nucleic acid-based, biosensor-based and immunological-based methods. This review emphasizes on the principles and application of recent rapid methods for the detection of foodborne bacterial pathogens. Detection methods included are simple polymerase chain reaction (PCR), multiplex PCR, real-time PCR, nucleic acid sequence-based amplification (NASBA), loop-mediated isothermal amplification (LAMP) and oligonucleotide DNA microarray which classified as nucleic acid-based methods; optical, electrochemical and mass-based biosensors which classified as biosensor-based methods; enzyme-linked immunosorbent assay (ELISA) and lateral flow immunoassay which classified as immunological-based methods. In general, rapid detection methods are generally time-efficient, sensitive, specific and labor-saving. The developments of rapid detection methods are vital in prevention and treatment of foodborne diseases. © 2015 Law, Ab Mutalib, Chan and Lee.


Lee L.-H.,University of Selangor | Azman A.-S.,University of Selangor | Zainal N.,University of Selangor | Zainal N.,University of Malaya | And 3 more authors.
International Journal of Systematic and Evolutionary Microbiology | Year: 2015

Strain MUSC 117Twas isolated from mangrove soil of the Tanjung Lumpur forest in Pahang, Malaysia. This bacterium was yellowish-white pigmented, Gram-staining-positive, rod–coccus shaped and non-motile. On the basis of 16S rRNA gene sequence, strain MUSC 117Texhibited highest sequence similarity to Sinomonas atrocyanea DSM 20127T(98.0%), Sinomonas albida LC13T(97.9%) and Sinomonas soli CW 59T (97.8%), and lower (<97.6%) sequence similarity to other species of the genus Sinomonas. DNA–DNA hybridization experiments revealed a low level of DNA–DNA relatedness (less than 27%) between strain MUSC 117Tand closely related species. Chemotaxonomically, the peptidoglycan type was A3α, containing the amino acids lysine, serine, glycine, alanine, glutamic acid and muramic acid. The whole-cell sugars detected were rhamnose, ribose, glucose, galactose and a smaller amount of mannose. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and five unidentified glycolipids. The major fatty acids (.10.0%) of the cell membrane were anteiso-C15: 0(39.4%), C18: 1ω7c (17.7%), anteiso-C17: 0(17.2%) and iso-C16: 0(11.4%). The predominant respiratory quinones detected were MK-9(H2) and MK-9. The DNA G+C content was 67.3 mol%. A comparison of BOX-PCR fingerprints indicated that strain MUSC 117Trepresented a unique DNA profile. Results based on a polyphasic approach showed that strain MUSC 117Trepresents a novel species of the genus Sinomonas, for which the name Sinomonas humi sp. nov. is proposed. The type strain of Sinomonas humi sp. nov. is MUSC 117T(5DSM 29362T=MCCC 1K00410T=NBRC 110653T). © 2015 IUMS.


Lee L.-H.,University of Selangor | Azman A.-S.,University of Selangor | Zainal N.,University of Malaya | Eng S.-K.,University of Selangor | And 3 more authors.
International journal of systematic and evolutionary microbiology | Year: 2014

Strain MUSC 115(T) was isolated from mangrove soil of the Tanjung Lumpur river in the state of Pahang, Peninsular Malaysia. Cells of this strain stained Gram-positive and were non-spore-forming, short rods that formed yellowish-white colonies on different agar media. The taxonomy of strain MUSC 115(T) was studied by a polyphasic approach, and the organism showed a range of phylogenetic and chemotaxonomic properties consistent with those of the genus Microbacterium. The cell-wall peptidoglycan was of type B2β, containing the amino acids ornithine, alanine, glycine, glutamic acid and homoserine. The muramic acid was of the N-glycolyl form. The predominant menaquinones detected were MK-12, MK-13 and MK-11. The polar lipids consisted of phosphatidylglycerol, phosphoglycolipid, diphosphatidylglycerol, two unidentified lipids, three unidentified phospholipids and four unidentified glycolipids. The major fatty acids of the cell membrane were anteiso-C15:0 and anteiso-C17:0. The whole-cell sugars detected were ribose, glucose, mannose and galactose. Based on the 16S rRNA gene sequence, strain MUSC 115(T) showed the highest sequence similarity to Microbacterium immunditiarum SK 18(T) (98.1%), M. ulmi XIL02(T) (97.8%) and M. arborescens DSM 20754(T) (97.5%) and lower sequence similarity to strains of other species of the genus Microbacterium. DNA-DNA hybridization experiments revealed a low level of DNA-DNA relatedness (less than 24%) between strain MUSC 115(T) and the type strains of closely related species. Furthermore, BOX-PCR fingerprint comparison also indicated that strain MUSC 115(T) represented a unique DNA profile. The DNA G+C content determined was 70.9 ± 0.7 mol%, which is lower than that of M. immunditiarum SK 18(T). Based on the combination of genotypic and phenotypic data, it is proposed that strain MUSC 115(T) represents a novel species of the genus Microbacterium, for which the name Microbacterium mangrovi sp. nov. is proposed. The type strain is MUSC 115(T) ( = MCCC 1K00251(T) = DSM 28240(T) = NBRC 110089(T)). IUMS.


PubMed | University of Malaya, UKM Medical Molecular Biology Institute UMBI and University of Selangor
Type: | Journal: Marine genomics | Year: 2015

Isolated from intertidal soil, Streptomyces pluripotens MUSC 135(T) produces a broad-spectrum bacteriocin against the pathogens methicillin-resistant Staphylococcus aureus (MRSA) ATCC BAA-44(T), Salmonella typhi ATCC 19430(T) and Aeromonas hydrophila ATCC 7966(T). Along with antibacterial activity, fermentation studies on strain MUSC 135(T) revealed production of antioxidant(s). The high quality draft genome of MUSC 135(T) comprises 7,480,269 bp with G+C content of 70.00%. Through bioinformatics analysis, 72 gene clusters identified in the genome were associated with the production of secondary metabolites, which may shed light on the identity of these bioactive compounds.


PubMed | UKM Medical Molecular Biology Institute UMBI
Type: Journal Article | Journal: Asian Pacific journal of cancer prevention : APJCP | Year: 2016

Lymph node metastasis (LNM) in papillary thyroid cancer (PTC) has been shown to be associated with increased risk of locoregional recurrence, poor prognosis and decreased survival, especially in older patients. Hence, there is a need for a reliable biomarker for the prediction of LNM in this cancer. MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene translation or degradation and play key roles in numerous cellular functions including cell-cycle regulation, differentiation, apoptosis, invasion and migration. Various studies have demonstrated deregulation of miRNA levels in many diseases including cancers. While a large number of miRNAs have been identified from PTCs using various means, association of miRNAs with LNM in such cases is still controversial. Furthermore, studies linking most of the identified miRNAs to the mechanism of LNM have not been well documented. The aim of this review is to update readers on the current knowledge of miRNAs in relation to LNM in PTC.

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