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.
Keyword: 

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite