Abstract
In my search of microbial source of novel enzymes, a marine actinomycetes, A1460, producing haloperoxidase was isolated from macroalgae from south sea, Korea and studied for physiological and biochemical properties. The haloperoxidation reaction was followed by the bromination of phenol red in the presence of hydrogen peroxide and potassium bromide. The haloperoxidase was partially purified from the cell extract with $35\sim75%$ ammonium sulfate precipitation, High-Q anion exchange chromatography, gel filtration chromatography, hydroxyapetite chromatography and hydrophobic interaction chromatography to a yield of 42% and purification fold of 70. This enzyme showed relatively high heat stability without losing 50% of activity after 1 hr incubation at $60^{\circ}C$. The highest activity was found at $45^{\circ}C$, and the optimal pH was about pH 7, but higher stability was observed at pH 8. Azide and cyanide ion showed strong inhibition at less than 1 $\mu M$ level suggesting that the enzyme was Fe ion dependent haloperoxidase.
Haloperoxidase를 생산하는 미생물을 분리하기 위하여 국내 연근해와 남북극 등의 해양시료에서 분리된 방선균 균주를 대상으로 탐색을 수행하여 남해 백도 해조류 추출물로부터 분리된 한 종류의 방선균(#1460)에서 높은 haloperoxidase 활성이 확인되었다. 본 균주의 생리.생화학적 특성은 Streptomyces 속과 유사하며 생산되는 haloperoxidase는 세포 조 추출물로부터 ammonium sulfate precipitation, High-Q column chromatography, gel permeation chromatography, Hydroxyapetite chromatography 그리고 hydrophobic interaction chromatography를 통하여 42%의 수율과 purification fold 70으로 정제하였다. 본 효소의 최적 반응 pH는 7이고 pH 8에서 더 높은 안정성을 보여 $60^{\circ}C$에서 1시간 반응에 효소활성의 50%가 생존한다. 또 cyanide와 azide 이온에 의해 강한 저해현상을 보인다.
