Judul: Construction of Vector, Expression and Purification of Recombinant Plantaricin F in Escherichia coli
Abstrak: Bakteriosin merupakan protein antimikroba yang dihasilkan oleh sejumlah besar bakteri. Salah satu kelompok bakteri yang mampu menghasilkan bakteriosin adalah bakteri asam laktat (BAL). Bakteriosin yang dihasilkan oleh bakteri asam laktat aman untuk dikonsumsi oleh manusia karena dapat dengan mudah terdegradasi oleh enzim proteolitik dari saluran pencernaan. Salah satu jenis bakteriosin yang berpotensi untuk dijadikan sebagai bahan pengawet makanan adalah plantarisin. Plantarisin F rekombinan merupakan salah satu bakteriosin yang diisolasi dari Lactobacillus plantarum S34. Penelitian ini bertujuan untuk mengkonstruksi vektor ekspresi, ekspresi dan purifikasi plantarisin F rekombinan yang terdiri dari tiga macam struktur plantarisin F yaitu plnF pre-mature, plnF mature dan plnF mutan di Escherichia coli., Bacteriocin antimicrobial protein is produced by large number of bacteria. Bacteriocin produced by bacteria is synthesized at ribosome that has antibacterial activity. Lactic acid bacteria (LAB) belongs to a group of gram-positive bacteria are able to produce bacteriocin that can be applied in the food industry as a natural preservative. Bacteriocin is safe for human consumption because it can be easily degraded by proteolytic enzymes, especially proteases in digestive tract. Bacteriocin has been applied in food industry, especially in dairy products, eggs, vegetables and meat. Plantarisin F is one of bacteriocin that can be used as an alternative for food preservation. The objective of this research is to construct expression vectors, express and purify recombinant plantaricin F composed of these plantarisin F, i.e. pre-mature plantaricin, mature plantaricin and mutant plantaricin.
Keyword: Bacteriocin, Escherichia coli, pET32a, recombinant plantaricin F.

Judul: Konstruksi Gen Penyandi Plantaricin S dari Lactobacillus plantarum S34
Abstrak: Bacteriocins are antibacterial peptides that commonly used as food biopreservative. Bacteriocins were produced by both either Gram positive or Gram negative bacteria, one of them is Lactobacillus plantarum S34 isolated from beef bekasam. L. plantarum S34 produced bacteriocins called plantaricin. PlnS gene is gene that encoding plantaricin. The study purposed is to isolate plnS gene from L. plantarum S34. The plnS gene amplified by PCR (Polymerase Chain Reaction) technique, and then cloned into cloning vector pGEM-T Easy and transformed into E. coli DH5α. Transformation gene using heat shock method. Selection of transformants using the blue and white colonies. Gene amplification produces plnS gene amplicon size about ±500 bp. PlnS gene ligation with pGEM-T Easy (3015 bp) vector generating plasmid size about ±3500 bp. The confirmation of white colonies from blue-white screening was carried out with PCR colony, generated amplicons size was about ±500 bp. Recombinant plasmid in colony 2 was confirmed by restricition analysis using SalI and NcoI. The result showed that the gene insert had expected size ±500 bp.
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Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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