Judul: Analisis gen soluble metan monooksigenase (sMMO) bakteri metanotrof asal sawah dengan primer 534f dan 1393r
Abstrak: Bakteri metanotrof merupakan bakteri Gram negatif, bersifat aerob, dan menggunakan metan sebagai sumber karbon untuk menghasilkan energinya. Karakteristik penting dari metanotrof ini ialah memiliki enzim metan monooksigenase (MMO) yang dapat mengkatalisis metan menjadi metanol. Enzim MMO terbagi ke dalam dua tipe, yaitu particulate MMO (pMMO) dan soluble MMO (sMMO). Semua bakteri metanotrof mampu mengekspresikan enzim pMMO, namun sMMO hanya dimiliki beberapa bakteri metanotrof saja. Isolat-isolat bakteri metanotrof (BGM 1, BGM 5, BGM 9,dan SKM 14) yang berasal dari sawah Bogor dan Sukabumi, hanya isolat BGM 9 yang menunjukkan adanya aktivitas enzim sMMO dengan metode Cholorimetric Plate Assay. Fragmen amplikon dari BGM 9 diamplifikasi dan disekuensing. Sekuen yang diperoleh dianalisis dengan menggunakan perangkat bioinformatik seperti BLAST-N dan BLAST-X. Analisis sekuen amplikon menggunakan program BLAST-N dan BLAST-X berturut-turut menunjukkan kemiripan dengan sekuen pada genom Azorhizobium caulinodans ORS 571 (92%) dan gen protein S3 pada ribosom 30S Xanthobacter autotrophicus Py2 (90%). Ketidaksesuaian hasil analisis tersebut dengan gen target diduga disebabkan oleh primer yang kurang spesifik dan keterbatasan informasi database di genetik tentang mikroba dari daerah tropis.
Keyword: Bakteri metanotrof, Enzim metan monooksigenase(MMO), Soluble metan monooksigenase

Judul: Karakterisasi Gen Particulate Methane Monooxygenase (pMMO) Bakteri Metanotrof Asal Sawah
Abstrak: Metanotrophic bacteria are a methane oxidizing bacteria that have specific enzyme called methane monooxygenase (MMO). Application of metanotrophic bacteria can reduce emission of methane in rice fields. There are two types of MMO enzymes, i.e. soluble MMO (sMMO) and particulate MMO (pMMO). The pMMO enzyme is a membrane-bound enzyme that is present in all metanotrophic bacteria. BGM 1 and SKM 14 isolates showed a different colony morphology when grown on Nitrate Mineral Salt (NMS) medium + 1% methanol. The pMMO gene amplification using A189f and A682r primer showed a ~300 bp and ~500 bp of DNA band for BGM 1 and SKM 14 isolates respectively. The sequences were analyzed using BLAST-N and BLAST-X program. Analysis of amplicon sequence from BGM 1 using BLAST-N and BLAST-X program showed highest similarity with sequence of gene (87%) and amino acid in protein (71%) acyl-coA dehydrogenase Xanthobacter autotrophicus Py2 respectively. Whereas analysis of amplicon sequence from SKM 14 using BLAST-N and BLAST-X program showed highest similarity with sequence of gene (84%) and amino acid in protein (62%) subunit B cytochrome bc1 Sinorhizobium fredii HH103 respectively.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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