Hairul Azman Roslan - Academia.edu (original) (raw)

Papers by Hairul Azman Roslan

Pertanika Journal of Tropical Agricultural Science, 2008

Isochorismate synthase (ICS) is a key enzyme that catalyses the conversion of chorismate to isoch... more Isochorismate synthase (ICS) is a key enzyme that catalyses the conversion of chorismate to isochorismate which is then channelled to other secondary product such as the anthraquinones. A near complete cDNA was isolated through RT-PCR technique. Characterization of this gene is important in characterising its role in the production of anthraquinones in the Rubiaceae plant family. Anthraquinones are known for their medicinal properties and can be found in Rubiaceae especially in roots. In this study, total RNA was extracted from roots of 'mengkudu' using modified CTAB method. The total RNA was subjected to first strand synthesis using oligo-dT18 primer and M-MuLV reverse transcriptase. Subsequently, PCR technique using primers designed from conserved ICS domains from other plants were used to isolate an internal conservative region of 426 bp. The cDNA was subsequently sequenced and verified using BLASTn program through the NCBI Genebank database, which showed a high sequence identity (72%) to the ICS from Catharanthus roseus. Based on this sequence, 3'RACE was performed to obtain the 3'-end of the gene and a 1036 bp 3'-fragment was generated. Apart from that, another PCR managed to generate a fragment of 491 bp upstream of the cDNA. Both fragments were sequenced and verified. Contig analyses and assembly of the partial cDNAs generated showed a near complete cDNA of 1872 bp. Sequence analysis of this partial cDNA showed a high degree of identity with ICS cDNA from other plants with the highest identity of 72% with ICS from C. roseus. Deduced amino acid showed a high similarity with Rubia cardifolia ICS of 85%.

Morinda citrifolia or the commercially name as Noni is a type of plant from Rubiaceae (coffe fami... more Morinda citrifolia or the commercially name as Noni is a type of plant from Rubiaceae (coffe family), and subfamily of Rubioideae. Morinda citrifolia is a significant source of both traditional and modern medical applications (Tan & Roslan, 2008). Isochorismate synthase (ICS) is an enzyme from Morinda citrifolia which catalyse the formation of salicyclic acid (SA). Salicyclic acid is a type of phytohormone that functions in plant defence (Strawn et al, 2007). In previous studies, it has been shown that salicyclic acid can be produced through the formation of isochorismate (Chen et al, 2009). Partial mcICS cDNA from Morinda citrifolia had been previously isolated (Tan & Roslan, 2008) but have not been characterised. Therefore this project aims to characterise the cDNA via the construction of an expression vector containing the mcICS cDNA and expression of the cDNA in an expression host. The expressed protein is then analysed using sodium-dodecyl sulphate polyacrylamide gel electropho...

Breeding Science, 2015

Kenaf (Hibiscus cannabinus L.; Family: Malvaceae), is multipurpose crop, one of the potential alt... more Kenaf (Hibiscus cannabinus L.; Family: Malvaceae), is multipurpose crop, one of the potential alternatives of natural fiber for biocomposite materials. Longer fiber and higher cellulose contents are required for good quality biocomposite materials. However, average length of kenaf fiber (2.6 mm in bast and 1.28 mm in whole plant) is below the critical length (4 mm) for biocomposite production. Present study describes whether fiber length and cellulose content of kenaf plants could be enhanced by increasing GA biosynthesis in plants by overexpressing Arabidopsis thaliana Gibberellic Acid 20 oxidase (AtGA20ox) gene. AtGA20ox gene with intron was overexpressed in kenaf plants under the control of double CaMV 35S promoter, followed by in planta transformation into V36 and G4 varieties of kenaf. The lines with higher levels of bioactive GA (0.3-1.52 ng g(-1) fresh weight) were further characterized for their morphological and biochemical traits including vegetative and reproductive growth, fiber dimension and chemical composition. Positive impact of increased gibberellins on biochemical composition, fiber dimension and their derivative values were demonstrated in some lines of transgenic kenaf including increased cellulose content (91%), fiber length and quality but it still requires further study to confirm the critical level of this particular bioactive GA in transgenic plants.

Pakistan Journal of Biological Sciences, 2013

Morinda citrifolia, is a valuable medicinal plant with a wide range of therapeutic properties and... more Morinda citrifolia, is a valuable medicinal plant with a wide range of therapeutic properties and extensive transformation study on this plant has yet been known. Present study was conducted to establish a simple and reliable transformation protocol for M. citrifolia utilising Agrobacterium tumefaciens via direct seed exposure. In this study, the seeds were processed by tips clipping and dried and subsequently incubated in inoculation medium. Four different parameters during the incubation such as incubation period, bacterial density, temperature and binary vectors harbouring beta-glucuronidase (GUS) gene (pBI121 and pGSA1131), were tested to examine its effect on transformation efficiency. The leaves from the treated and germinated seedlings were analysed via Polymerase Chain Reaction (PCR), histochemical assay of the GUS gene and reverse transcription-PCR (RT-PCR). Results of the study showed that Agrobacterium strain LBA4404 with optical density of 1.0 and 2 h incubation period were optimum for M. citrifolia transformation. It was found that various co-cultivation temperatures tested and type of vector used did not affect the transformation efficiency. The highest transformation efficiency for M. citrifolia direct seed transformation harbouring pBI121 and pGSA1131 was determined to be 96.8% with 2 h co-cultivation treatment and 80.4% when using bacterial density of 1.0, respectively. The transformation method can be applied for future characterization study of M. citrifolia.

ISRN Molecular Biology, 2012

Alcohol dehydrogenase (Adh) is a versatile enzyme involved in many biochemical pathways in plants... more Alcohol dehydrogenase (Adh) is a versatile enzyme involved in many biochemical pathways in plants such as in germination and stress tolerance. Sago palm is plant with much importance to the state of Sarawak as one of the most important crops that bring revenue with the advantage of being able to withstand various biotic and abiotic stresses such as heat, pathogens, and water logging. Here we report the isolation of sago palm Adh cDNA and its putative promoter region via the use of rapid amplification of cDNA ends (RACE) and genomic walking. The isolated cDNA was characterized and determined to be 1464 bp long encoding for 380 amino acids. BLAST analysis showed that the Adh is similar to the Adh1 group with 91% and 85% homology with Elaeis guineensis and Washingtonia robusta, respectively. The putative basal msAdh1 regulatory region was further determined to contain promoter signals of TATA and AGGA boxes and predicted amino acids analyses showed several Adh-specific motifs such as the two zinc-binding domains that bind to the adenosine ribose of the coenzyme and binding to alcohol substrate. A phylogenetic tree was also constructed using the predicted amino acid showed clear separation of Adh from bacteria and clustered within the plant Adh group.

TheScientificWorldJournal, 2014

beta-D-N-Acetylhexosaminidase, a family 20 glycosyl hydrolase, catalyzes the removal of β-1,4-lin... more beta-D-N-Acetylhexosaminidase, a family 20 glycosyl hydrolase, catalyzes the removal of β-1,4-linked N-acetylhexosamine residues from oligosaccharides and their conjugates. We constructed phylogenetic tree of β-hexosaminidases to analyze the evolutionary history and predicted functions of plant hexosaminidases. Phylogenetic analysis reveals the complex history of evolution of plant β-hexosaminidase that can be described by gene duplication events. The 3D structure of tomato β-hexosaminidase (β-Hex-Sl) was predicted by homology modeling using 1now as a template. Structural conformity studies of the best fit model showed that more than 98% of the residues lie inside the favoured and allowed regions where only 0.9% lie in the unfavourable region. Predicted 3D structure contains 531 amino acids residues with glycosyl hydrolase20b domain-I and glycosyl hydrolase20 superfamily domain-II including the (β/α)8 barrel in the central part. The α and β contents of the modeled structure were fou...

BioMed research international, 2014

Sago palm (Metroxylon sagu) is a perennial plant native to Southeast Asia and exploited mainly fo... more Sago palm (Metroxylon sagu) is a perennial plant native to Southeast Asia and exploited mainly for the starch content in its trunk. Genetic improvement of sago palm is extremely slow when compared to other annual starch crops. Urgent attention is needed to improve the sago palm planting material and can be achieved through nonconventional methods. We have previously developed a tissue culture method for sago palm, which is used to provide the planting materials and to develop a genetic transformation procedure. Here, we report the genetic transformation of sago embryonic callus derived from suspension culture using Agrobacterium tumefaciens and gene gun systems. The transformed embryoids cells were selected against Basta (concentration 10 to 30 mg/L). Evidence of foreign genes integration and function of the bar and gus genes were verified via gene specific PCR amplification, gus staining, and dot blot analysis. This study showed that the embryogenic callus was the most suitable mat...

BioMed Research International, 2014

As a part of the study to explore the possible strategy for enhancing the shelf life of mango fru... more As a part of the study to explore the possible strategy for enhancing the shelf life of mango fruits, we investigated the changes in biochemical parameters and activities of ripening associated enzymes of Ashwina hybrid mangoes at 4-day regular intervals during storage at −10 ∘ C, 4 ∘ C, and 30 ± 1 ∘ C. Titratable acidity, vitamin C, starch content, and reducing sugar were higher at unripe state and gradually decreased with the increasing of storage time at all storage temperatures while phenol content, total soluble solid, total sugar, and nonreducing sugar contents gradually increased. The activities of amylase, -mannosidase, -glucosidase, and invertase increased sharply within first few days and decreased significantly in the later stage of ripening at 30 ± 1 ∘ C. Meanwhile polyphenol oxidase, -galactosidase, and -hexosaminidase predominantly increased significantly with the increasing days of storage till later stage of ripening. At −10 ∘ C and 4 ∘ C, the enzymes as well as carbohydrate contents of storage mango changed slightly up to 4 days and thereafter the enzyme became fully dormant. The results indicated that increase in storage temperature and time correlated with changes in biochemical parameters and activities of glycosidases suggested the suppression of -galactosidase and -hexosaminidase might enhance the shelf life of mango fruits.

3 Biotech, 2012

Sago palm, or Metroxylon sagu, is a hardy and versatile plant that is able to tolerate many stres... more Sago palm, or Metroxylon sagu, is a hardy and versatile plant that is able to tolerate many stresses, biotic and abiotic, during its growth. It is one of the plants that are able to grow in waterlogged area where others could not. Apart from that sago palm is also a source of starch, contributes economically to the people and an important export for the state of Sarawak. Despite the importance of sago palm especially in the production of starch and its ability to withstand stresses, so far, not many molecular studies have been reported on sago palm. To study the characters in sago palm, transcriptome analysis was conducted where it would give a better understanding of the plant development through gene expression. Here, we report the construction of a cDNA library and preliminary expressed sequence tags analysis from the young leaves of sago palm. A total of 434 clones were sequenced with inserts ranging from 1,000 to 3,000 bps with primary and amplified titers of 8 9 10 5 and 1.0 9 10 9 pfu/ml, respectively. Clustering of these sequences resulted in a set of 372 tentative unigenes comprising 340 singletons and 32 contigs. The database was also annotated with BLAST2GO which showed that majority of the transcripts were involved in primary metabolism and stress tolerance.

3 Biotech, 2011

Chitinase is an enzyme that catalyzes the degradation of chitin, commonly induced upon the attack... more Chitinase is an enzyme that catalyzes the degradation of chitin, commonly induced upon the attack of pathogens and other stresses. A cDNA (MsChi1) was isolated from Metroxylon sagu and expressed predominantly in the inflorescence tissue of M. sagu, suggesting its role in developmental processes. The chitinase cDNA was detected and isolated via differential display and rapid amplification of cDNA ends (RACE). Primers specific to M. sagu chitinase were used as probes to amplify the 3 0 -end and 5 0end regions of chitinase cDNA. Transcript analysis showed that chitinase is expressed in inflorescence and meristem tissues but was not detected in the leaf tissue. Sequence analysis of amplified cDNA fragments of 3 0 -end and 5 0 -end regions indicated that the chitinase cDNA was successfully amplified. The M. sagu chitinase cDNA isolated was approximately 1,143 bp long and corresponds to 312 predicted amino acids. Alignments of nucleotide and amino acid have grouped this chitinase to family 19 class I chitinase.

World Journal of Microbiology and Biotechnology, 2011

White rot fungi are good lignin degraders and have the potential to be used in industry. In the p... more White rot fungi are good lignin degraders and have the potential to be used in industry. In the present work, Phellinus sp., Daedalea sp., Trametes versicolor and Pycnoporus coccineus were selected due to their relatively high ligninolytic enzyme activity, and grown on Acacia mangium wood chips under solid state fermentation. Results obtained showed that manganese peroxidase produced is far more compared to lignin peroxidase, suggesting that MnP might be the predominating enzymes causing lignin degradation in Acacia mangium wood chips. Cellulase enzyme assays showed that no significant cellulase activity was detected in the enzyme preparation of T. versicolor and Phellinus sp. This low cellulolytic activity further suggests that these two white rot strains are of more interest in lignin degradation. The results on lignin losses showed 20-30% of lignin breakdown at 60 days of biodegradation. The highest lignin loss was found in Acacia mangium biotreated with T. versicolor after 60 days and recorded 26.9%, corresponding to the percentage of their wood weight loss recorded followed by P. coccineus. In general, lignin degradation was only significant from 20 days onwards. The overall percentage of lignin weight loss was within the range of 1.02-26.90% over the biodegradation periods. Microscopic observations conducted using scanning electron microscope showed that T. versicolor, P. coccineus, Daedalea sp. and Phellinus sp. had caused lignin degradation in Acacia mangium wood chips.

Journal of Experimental Botany, 2005

Controlled expression of transgenes in plants is key to the characterization of gene function and... more Controlled expression of transgenes in plants is key to the characterization of gene function and the regulated manipulation of growth and development. The alc gene-expression system, derived from the ®lamentous fungus Aspergillus nidulans, has previously been used successfully in both tobacco and potato, and has potential for use in agriculture. Its value to fundamental research is largely dependent on its utility in Arabidopsis thaliana. We have undertaken a detailed function analysis of the alc regulon in A. thaliana. By linking the alcA promoter to b-glucuronidase (GUS), luciferase (LUC) and green uorescent protein (GFP) genes, we demonstrate that alcR-mediated expression occurs throughout the plant in a highly responsive manner. Induction occurs within one hour and is dose-dependent, with negligible activity in the absence of the exogenous inducer for soil-grown plants. Direct application of ethanol or exposure of whole plants to ethanol vapour are equally effective means of induction. Maximal expression using soil-grown plants occurred after 5 days of induction. In the majority of transgenics, expression is tightly regulated and reversible. We describe optimal strategies for utilizing the alc system in A. thaliana.

Pertanika J. Trop. Agric. Sci, 2008

ABSTRACT Alcohol dehydrogenase (ADH) is an enzyme involved in pathways that respond to various st... more ABSTRACT Alcohol dehydrogenase (ADH) is an enzyme involved in pathways that respond to various stresses including environmental such as osmotic, wound and anaerobic condition. ADH is capable of catalyze the interconversion of alcohols to their corresponding aldehydes or ketones. Recently, Adh activity has been identified in various sago palm tissues and a full construct of Adh cDNA (msAdh1) with approximately 1.3 Kb in length has been generated through rapid amplification of cDNA ends (RACE) technique. To further investigate the function of msAdh1, the msAdh1 cDNA of approximately 1.1 Kb in length was constructed and cloned in the expression vector pET-41a(+). The pET41-a(+)/msAdh1 was then expressed in an expression host, E. coli strain BL21 (DE3). Subsequently purification of msAdh1 protein under denaturing and native condition was carried out using Ni-NTA spin column. The crude extract of total protein was visualized on native PAGE and 3% agarose gel. Several potential bands were visualized on PAGE when stained with Adh-specific staining solution.

Aims: Phytophthora capsici and Fusarium solani are common fungal pathogens causing severe disease... more Aims: Phytophthora capsici and Fusarium solani are common fungal pathogens causing severe diseases that lead to economic loss in pepper industry, especially in Sarawak. In response to the infections, chemical approach is more common; nevertheless, biological control is more favorable to control fungal pathogens. Biological control approach greatly reduces the problems associated with chemical applications and it restores balance of the natural environment.

Protease is a group of enzymes that degrades polypeptides. Cysteine protease usually can be found... more Protease is a group of enzymes that degrades polypeptides. Cysteine protease usually can be found in the animal, plant kingdoms and also in viruses and bacteria. It has many roles in plant cell physiology and development such as in embryogenesis, tracheary element differentiation, germination of seeds, leaf and flower senescence, and also in response to biotic and abiotic stresses. Cysteine protease was previously found to be present in sago palm via expressed sequence tags analysis of young sago palm leaf. In this project, the aim is to clone Metroxylon sagu cysteine protease (msCPR) cDNA into a bacterial expression vector, pET41a+ (Novagen). The cloning will be done via Polymerase Chain Reaction (PCR) method, followed by verification analyses such as using restriction enzyme and sequencing of the PCR product.. The putative cDNA will be further analysed in a bacterial expression system using Rosetta cells (E.coli) for determination of function

Protease is a group of enzymes that degrades polypeptides. The enzyme cysteine protease in partic... more Protease is a group of enzymes that degrades polypeptides. The enzyme cysteine protease in particular has many roles in plant cells physiology and development such as in embryogenesis, tracheary element differentiation, germination of seeds, leaf and flower senescence, and in response to biotic and abiotic stresses. Cysteine protease was found to be present in sago palm previously via expressed sequence tags analysis of young sago palm leaf. In this project, the main aim is to construct Metroxylon sagu Cysteine Protease (msCPR) cDNA into expression vector pET41a+. For this work a cysteine protease cDNA was cloned into a bacterial expression vector, pET41a+. Cloning was done via Polymerase Chain Reaction (PCR) method, followed by plasmid transformation and subsequent restriction enzyme analysis to verify the transformants. The cysteine protease needed to be cloned into pET41a+ for expression in Rosetta cells (E.coli) and analysis of expressed protein is then done using Sodium dedecyl...