Interactions of the L, P and Np Proteins of the Newcastle Disease Virus

The large (L) and phospho- (P) proteins together with the nucleocapsid (NP) protein of Newcastle disease virus (NDV) are involved in the transcription and replication of the viral genome. The L protein interacts with the P protein to form the active RNA dependent RNA polymerase complex which then acts on the ribonucleoprotein (NP:RNA) comprising the single stranded negative RNA genome which is tightly bound to the NP protein. Amino acid sequence alignment of the L proteins of several nonsegmented negative stranded RNA viruses revealed six highly conserved domains described as Domains I to VI which were proposed to specify the essential activities common to the polymerases of these virus. In this study, the individual domains of the L gene of NDV strain AF2240 were cloned separately into pCITE2b plasmid expression vector. An in vitro protein binding assay was used to determine the conserved domains on L protein that interact with the purified NP protein. The full length purified NP protein was immobilized on a solid phase and then interacted with radiolabelled [35S]-L domains synthesized in rabbit reticulocyte lysates. The interaction affinity was quantitated by measuring the radioactivity that was retained on the solid phase. Domain III, which is located between amino acids 631-861, was shown to be highly interactive with the NP protein. In addition, Domains II (amino acid 502 to 607), IV (amino acid 904 to 1071) and V (amino acid 1488 to 1597) showed weak interaction with the NP protein. On the other hand, the interactions between in vitro translated L protein domains with the P protein were determined by the immunoprecipitation method. In this approach, the L-P complexes which formed in the mixture were captured with anti-myc monoclonal antibody conjugated to protein G agarose. These complexes were precipitated and analysed by autoradiography. Domain V was observed to exhibit the strongest binding with P whereas Domains III and IV showed weaker binding capacities. In conclusion, the core domains of L comprising Domains III, IV and V were interacted with both P and NP proteins which are involved in transcription and replication, but their levels of interactions differed

Effects of Merkel Cell Polyomavirus T Antigen Expression on Cell Transformation of Merkel Cells

Merkel cell carcinoma (MCC) is a rare but highly metastatic skin cancer that affects immunosuppressed individuals. The MCC tumour arises from mechanoreceptor merkel cells in the basal layer of the epidermis and is able to spread through the dermal lymphatic system. Merkel cell polyomavirus (MCPyV) has been detected in the majority of MCC tumour samples. Truncation mutations of the large tumour antigen (LT) are observed in the integrated genome rendering the virus replication defective. These replication-disabling mutations are only present in MCPyV isolates found in cancers and absent from viruses derived from non-tumour tissues. As such aberrant expression of truncated LT (tLT) and small T (ST) antigens is thought to be implicated in MCC development. Elucidating the cellular pathways affected by the MCPyV T antigens involved in oncogenesis and tumour progression is essential to understand the effects of these oncoproteins in cellular transformation and tumourigenesis. A quantitative proteomic approach has been used to identify cellular proteins and pathways that are differentially expressed upon expression of MCPyV tLT. Bioinformatic analysis of the stable isotope labelling by amino acid in cell culture (SILAC) datasets highlight several pathways that are dysregulated upon tLT expression. These pathways include cell cycle regulation, cell death and survival, and cell-cell connections. Further analysis confirmed the effects of MCPyV tLT on these pathways showing alterations within the cell cycle, specifically disrupting the G1 checkpoint to enhance entry to the Sphase, which may prolonged the S phase to allow viral DNA replication. In addition, results suggest that MCPyV tLT expression may also delay the apoptosis-inducing properties of various compounds but was not capable to fully inhibit the apoptotic cascade. In contrast, although proteomic analysis highlighted a number of cell-cell connections related pathways to be differentially altered upon tLT expression, follow up experiments were not able to confirm these results

In vitro and in vivo cytotoxic effects of chlorella against various types of cancer

Chlorella is one of the microalgae that had been studied intensively owing to its rapid growth and easily cultured at a large scale compared to other microalgae and valuable nutrient compositions. Numerous studies have observed that Chlorella possess various health benefit including antioxidant, anti-cholesterol, anti-inflammatory, and antiproliferative effect against many types of cancer. In this review paper, the effects of various Chlorella species against cancer cells and animal induced cancer are discussed and an overview on Chlorella is briefed. The Chlorella deleterious effect on cancer through various mechanisms such as enhancement of immune system and apoptosis; improving lipid peroxidation; synthesis and expression of the protein-degrading matrix; and preventing the formation of new blood vessels are elaborated as well. Based on the findings of many studies reported in this article, it can be suggested that Chlorella has the potential in supporting cancer therapy and may develop to become an anti-cancer agent

Polycaprolactone/cellulose acetate loaded psidium guajava essential oil electrospun nanofibrous mat dressing for healing wounds

Natural products and essential oils of medicinal plants are extensively employed in wound healing, particularly in the pharmaceutical industry. Essential oils obtained from Psidium guajava were utilised as an antibacterial agent against Bacillus subtilis, Staphylococcus aureus, and Enterococcus faecalis, and to control drug-resistant strains. In this study, electrospinning for applications in antimicrobial activity and drug delivery systems was used to develop biocomposite nanofibers of Polycaprolactone (PCL)/Cellulose Acetate (CA) and Psidium guajava essential oil (PGEO). Images from the FESEM revealed that the mean fire diameters were 120 nm for the PCL/CA and 223 nm for PCL/CA/PGEO biocomposite nanofibers. The diameters of the nanofibers were increased following the addition of PGEO into PCL/CA nanofibers. Furthermore, FTIR studies revealed the -OH peak in pure electrospun PCL/CA and PCL/CA/PGEO, lacking pure PGEO nanofibrous mats. These findings reflect that Psidium guajava essential oil/PCL/CA electrospun nanofibers are promising candidates for presenting bioactive compounds in wound management or other approaches for wound healing and bacterial infections

Medicinal properties screening of Mallotus paniculatus extract

Traditionally, Mallotus paniculatus (Balik Angin) plant is used in the treatment of various diseases in rural areas such as remedy after childbirth, wound healing and fever. In this present study, four medicinal properties of the plant were investigated which included antibacterial, antifungal, anticancer and antioxidant activities. Materials and Methods: Potential medicinal compounds were extracted from the plant leaves by sonication with 3 different solvents namely ethanol, ethyl acetate and hexane respectively. The antibacterial and antifungal properties were determined using disc diffusion agar and broth dilution assay, the antioxidant activity by DPPH scavenging assay and the anticancer effect by MTT assay. Results: From the screening of the medicinal properties, M. paniculatus leave extracts were shown to possess antibacterial, antioxidant and anticancer properties but not antifungal properties. Ethanolic and ethyl acetate extracts of the leave were active against gram positive bacteria (Staphylococcus aureus and Bacillus subtilis) but not gram negative bacteria (Pseudomonas aeruginosa and Escherichia coli). The antioxidant activity of the ethanolic crude extract was high; with IC50 of 30 μg/ml comparable with the positive controls; ascorbic acid and butylated hydroxytoluene (BHT). Both ethanolic and ethyl acetate extracts were cytotoxic against breast cancer (MCF7), colon cancer (HT-29), cervix cancer (Hela) cell lines. Conclusion: M. paniculatus leave extract has many potential medicinal values for further studies

In vitro appraisal of antibacterial activity of Entada spiralis’s leaves extracts against phytopathogenic bacteria Erwinia chrysanthemi and Erwinia carotovora

Entada spiralis Ridl. or also known as ‘akar beluru’ or ‘akar sintok’, is one of the least studied species in the Fabaceae family. The species was famous for its soap-like properties in which the natives use them as soap and shampoo for hygiene and treating itchiness. The phytochemicals and biochemicals properties of this plant have always been an interesting area to be discovered, as the study of the species is still scanty. In this study, the aim is to evaluate the antibacterial effects of the E. spiralis leaves extracts against two Gram-negative phytobacteria species, Erwinia chrysanthemi (ATCC 437624) and Erwinia carotovora (ATCC 15713) for the discovery of the natural active bactericides. Hexane, dichloromethane, ethyl acetate and methanol were used as menstruum in producing the extracts through cold maceration method. The extracts were subjected to screening tests for identification of phytochemicals which revealed the presence of phenolics, terpenoids, saponins, coumarins, flavonoids, and tannins. Antibacterial activities of the extracts were assessed via Kirby-Bauer disk diffusion method by measuring the inhibition zones post-incubation for 24 hours at room temperature. While, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated through broth microdilution method after incubation at room temperature for 24 hours. Output data from this study showed that, methanol extract against E. chrysanthemi and ethyl acetate extract against E. carotovora have the maximum zone of inhibition in antibacterial susceptibility with 22.7 ± 0.6 mm and 26.3 ± 0.6 mm respectively at 400 mg/mL concentration. In accordance with MIC, E. chrysanthemi was revealed to be most susceptible in methanol extract with MIC value of 1.56 ± 0.00 mg/mL (MBC value at 3.13 ± 0.00 mg/mL). E. carotovora has been determined to be best susceptible also in ethyl acetate extracts with MIC values of 0.65 ± 0.23 mg/mL (MBC value at 2.60 ± 0.90 mg/mL)

Real-time cytotoxicity assay of water extracts Hibiscus rosa-sinensis

A real-time impedance-based electrochemistry assay was used for assessing the cytotoxicity effect of water extract Hibiscus Rosa-Sinensis on Vero cell line. In this study, H. rosa-sinensis was extracted by using the water extraction with three different concentration which were 200, 100 and 50 µg/mL. The phytochemical compounds in the extract were analyzed by using the Gas Chromatography-Mass Spectrometry (GC-MS). The GC-MS result showed that the extract contains bioactive compounds such as n-hexadecanoic acid, pentadecanoic acid, phenol, 2,4-bis(1,1- dimethylethyl) and octadecanoic acid that have bioactive properties such as cytotoxic and antioxidant. The cytotoxic effect of the extract on normal cell line was assessed by using Real-Time Cell Analysis (RTCA) instrument. The result showed that there was no significant cytotoxicity effect against Vero cell lines. This result showed that the real-time impedance-based assay can be utilized to monitor changes of the cells and to determine the inhibitory concentration of the extract

Application of Fractional Factorial Design (FFD) for Screening of Significant Factor in Influencing Succinic acid Production from Biodiesel Based Glycerol Using Escherichia Coli

The production of succinic acid from biodiesel based glycerol was carried out using Escherichia coli K12 MG1655 strain. The contribution of every parameter was evaluated and optimized using statistical modeling. A 2 6-1 fractional factorial design (FFD) was applied to screen the effect of substrate concentration, tryptone concentration, sodium carbonate concentration, inoculums density, pH and incubation period for Escherichia coli reaction on succinic acid production. The result of first order factorial design showed that glycerol concentration, tryptone concentration, incubation period and pH had significant positive effect (p>0.001) to the reaction. Meanwhile, inoculums density and Na2CO concentration exhibited insignificant effect in the reaction. In addition, interaction between inoculums density of substrate concentration and tryptone concentration, glycerol concentration and Na23CO concentration, tryptone concentration and pH, Na32CO concentration and incubation period and inoculums density with pH gave significant effects (p<0.001) to succinic acid production

Graduate student profile: Aini Norhidayah Mohamed, Msc (industrial chemistry) candidate

Aini Norhidayah Mohamed was born in Triang (Pahang) on October 6 1985, the last child of six siblings. Aini completed secondary education at Sekolah Menengah Sains Sultan Haji Ahmad Shah (Pekan) and pre-university at Kolej Matrikulasi Pulau Pinang before going off to Universiti Kebangsaan Malaysia to study Plant Biotechnology

Industrial link with KANEKA

Gebeng, Jan 14 - FIST's Industrial Chemistry and Material Technology groups met with KANEKA (M) Sdn. Bhd. to initiate academic and research collaborations