Aktivitas Pemotongan DNA Superkoil oleh Fraksi-fraksi Protein Daun Morinda citrifolia: The cleaving activity assay on supercoeled dna by protein fractions from Morinda citrifolia leaves - Perpustakaan UGM, i-lib ([Yogyakarta] : Universitas Gadjah Mada, 2002)
Uji aktivitas pemecahan terhadap DNA superkoil untai ganda.oleh fraksi protein daun Morinda citrifolia telah dilakukan. Penelitian ini bertujuan membandingkan aktivitas tiap fraksi protein berdasarkan kemampuan memotong DNA superkoil dalam upaya penapisan awal dan pencarian RIP (Ribosome-Inactivating Protein) dari daun tanaman Morinda citrifolia Fraksinasi protein dilakukan dengan menambahkan amonium sulfat dengan kadar 20%, 40%, 60%, 80% dan 100% untuk saturasi terhadap ekstrak gubal daun Morinda citrifolia dilanjutkan dengan sentrifugasi hingga diperoleh fraksi pengendapan F-20, F-40, F-60, F-80 dan F-100. Aktivitas pemotongan DNA superkoil dengan cara menginkubasi plasmid pUC19 dengan masing-masing fraksi pada kadar protein yang sama. Inkubasi dilakukan pada suhu kamar selama satu jam. Hasa menunjukkan bahwa protein yang paling besar kemampuan memotong DNA superkoil adalah fraksi F-80. Kata kunci : Ribosome-Inactivating Protein (RIP), DNA superkoil, fraksinasi, Morinda citrifolia L. ABSTRACT Study on supercoiled DNA cleaving activity assay of protein fraction from Morinda citrifolia leaf had been done. The aim of this research is to compare the supercoiled DNA cleaving abilities among the fractions. This is a preliminary screening to find RIP from Morinda citrifolia Fractionation of protein was done by adding Ammonium Sulphate up to 20%, 40%, 60%, 80% and 100% in the crude extract, saturated solution was then centifugated to get the pellet fractions and coded as F-20, F-40, F-60, F-80 and F-100. The mixture of pUC19 plasmid and protein fractions, in the same protein concentration were incubated at room temperature for one hour, the cleaving ability of protein fraction on supercoiled DNA.was investigated. The results indicated that protein fractions, of F-80 had the highest cleaving activity to supercoiled DNA.