Judul: Introduksi Gen Penyandi AHL Laktonase Asal Bacillus thuringensis SGT3g ke dalam Agrobacterium tumefaciens LBA4404.
Abstrak: Bakteri memanfaatkan quorum sensing (QS) untuk regulasi biofilm, faktor virulen, sintesis antibiotik, sporulasi, dan bioluminesen. Salah satu prinsip pengendalian virulensi bakteri fitopatogen dengan dasar QS adalah mencegah akumulasi AHL dengan mendegradasi molekul sinyal tersebut. Salah satu enzim pendegradasi AHL adalah enzim Acyl Homoserine Lactonase. AHL-laktonase sebagai salah satu enzim anti-QS dapat digunakan sebagai alternatif dalam pengendalian bakteri fitopatogen. Enzim ini umumnya ditemukan pada kelompok Bacillus dan disandikan oleh gen aiiA. Penelitian ini bertujuan untuk mengintroduksi gen penyandi AHL Laktonase pada Agrobacterium tumefaciens LBA4404 asal Bacillus thuringensis SGT3g. Amplifikasi gen AHL-laktonase dari isolat E.coli rekombinan yang membawa gen aiiA dari Bacillus thuringensis SGT3g dengan menggunakan primer aiiA mendapatkan pita DNA berukuran 800 bp. Gen aiiA asal Bacillus thuringensis SGT3g disisipkan ke dalam plasmid pCambia 2300 pada situs restriksi NcoI dan BglII. Analisa elektroforesis hasil restriksi pCambia 2300 rekombinan, plasmid pC-TE01, menggunakan enzim restriksi NcoI dan BglII menunjukkan adanya fragmen DNA berukuran 8743 bp (pCambia 2300) dan 800 bp (DNA sisipan aiiA) pada gel agarosa 1,5%.
Keyword: AHL-Laktonase, gen aiiA, Bacillus thuringensis, pCambia 2300

Judul: Introduksi Gen Penyandi AHL-Laktonase (aiiA) Bacillus cereus INT1c ke dalam Agrobacterium tumefaciens AGL 1.
Abstrak: Bakteri menggunakan mekanisme quorum sensing (QS) dalam berkoordinasi untuk melakukan suatu proses tertentu melalui perantara molekul sinyal asil homoserin lakton (AHL). Bakteri fitopatogen umumnya menggunakan mekanisme QS untuk mengekspresikan gen virulen pada saat menginfeksi tanaman. Penghambatan ekspresi gen virulen tersebut dapat dilakukan dengan mendegradasi senyawa AHL menggunakan AHL-laktonase. AHL-laktonase merupakan kelompok enzim yang berfungsi untuk menghidrolisis cincin lakton pada molekul AHL. Enzim ini umumnya ditemukan pada kelompok Bacillus spp. dan disandikan oleh gen aiiA. Penelitian ini bertujuan mengintroduksi gen penyandi AHL-Laktonase (aiiA) dari isolat Bacillus cereus INT1c dalam E.coli DH5α transforman ke dalam Agrobacterium tumefaciens AGL 1. Gen aiiA dari isolat Bacillus cereus INT1c dalam E.coli DH5α rekombinan berhasil diintroduksikan ke dalam sel A. tumefaciens AGL 1 melalui plasmid vektor pCambia 2300. Pemotongan plasmid rekombinan dengan menggunakan enzim Nco I dan Bgl II menunjukkan adanya fragmen DNA berukuran 8743 pb (pCambia 2300) dan 800 pb (gen aiiA) pada gel agarosa 1.0%. Hasil ini membuktikan bahwa plasmid rekombinan berhasil diintroduksikan dan telah diperbanyak di dalam sel A. tumefaciens AGL 1 transforman.
Keyword: Agrobacterium tumefaciens, AHL- laktonase, aiiA, Bacillus sp., introduksi, transformasi

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