IDENTIFIKASI BAKTERI PROTEOLITIK PADA RUMEN KAMBING KACANG BERDASARKAN ANALISIS GEN 16S RRNA

ABSTRAKRumen kambing merupakan salah satu sumber penghasil bakteri proteolitik yang mampu mendegradasi protein dengan menghasilkan enzim protease. Penelitian ini bertujuan untuk mengidentifikasi bakteri proteolitik yang terdapat pada rumen kambing kacang dan mengetahui hubungan kedekatan bakteri proteolitik dengan bakteri proteolitik lain yang ada di GenBank. Identifikasi dilakukan berdasarkan gen 16S rRNA melalui PCR-sekuensing. Sampel cairan rumen kambing kacang diambil dari tempat pemotongan kambing di rumah warga, Peunayong, Banda Aceh lalu ditanam ke media selektif, yaitu Skim Milk Agar. Kemudian diinkubasi secara anaerob pada suhu 390C selama 48 jam. Koloni bakteri proteolitik yang tumbuh dan memiliki zona bening terluas diambil untuk dilakukan isolasi DNA total dan diamplifikasi gen 16S rRNA. Hasil amplifikasi gen ini kemudian disekuensing, selanjutnya dianalisis secara biokomputasi dan dibandingkan dengan urutan nukleotida bakteri yang ada di NCBI untuk melihat homologi bakteri sampel dengan yang dideposit di GenBank. Hasil penelitian menunjukkan koloni bakteri proteolitik mempunyai zona bening terluas yaitu 2 mm dan dapat disimpulkan bahwa spesies bakteri pada rumen kambing kacang memiliki kedekatan dengan bakteri Bacillus subtilis strain 168 sebesar 93%

TOTAL BACTERIA AND IDENTIFICATION OF PROTEOLYTIC RUMINAL AND RETICULUM BACTERIA FROM LOCAL KACANG GOAT

This study aimed to calculate the total bacteria and to identify the proteolytic bacteria in rumen and reticulum of local Kacang goat. The samples used were the rumen and reticulum fluids of five goats at abattoirs in Banda Aceh. Isolation of proteolytic bacteria was carried out using skim milk agar with pour plate method and incubated at 39° C for 48 hours. The bacterial colonies morphology was observed and the total bacterial count was recorded. DNA of the widest proteolytic index colony was isolated, amplified, and sequenced. The results showed that the dominant colonies morphology was white with position inside the agar. The average of total proteolytic bacteria in goat rumen fluid and reticulum fluid were 6.416x106 CFU/mL and 2,382x107 CFU/mL, respectively. Isolates with the widest proteolytic index was Ru3 (2.5 mm) in the rumen which homology and phylogenetic tree analysis of 16S rRNA showed 93% sequence similarity with Bacillus subtilis, while in reticulum was Re1 (2.0 mm) which has 92% sequence similarity to Tatumella. It is concluded that the number of proteolytic bacteria in reticulum is greater than the number of proteolytic bacteria in the rumen of local kacang goat. Homology analysis in this study proved that the Ru3 and Re1 isolate were probably either a new species or unconfirmed species